Datasheet ST62T25BN3, ST62T25BN1, ST62T25BM6, ST62T25BM3, ST62T25BM1 Datasheet (SGS Thomson Microelectronics)

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Rev. 3.2

July 2001 1/105

ST6215C/ST6225C

8-BIT MCUs WITH A/D CONVERTER,

TWO TIMERS, OSCILLATOR SAFEGUARD & SAFE RESET

■ Memories

– 2K or 4K bytes Program memory (OTP,

EPROM, FASTROM or ROM) with read-out protection

– 64 bytes RAM

■ Clock, Re set and Supply M a nagement

– Enhanced reset system – Low Voltage Detector (LVD) for Safe Reset – Clock sources: crystal/ceramic resonator or

RC netwo rk, ex tern al cloc k, bac kup o scillat or

(LFAO) – Oscillator Safeguard (OSG) – 2 Power Saving Modes: Wait and Stop

■ Interrupt Management

– 4 interrupt vectors plus NMI and RESET – 20 external interrupt lines (on 2 vectors) – 1 external non-interrupt line

■ 20 I/ O P o rts

– 20 multifunctional bidirectional I/O lines – 16 alternate function lines – 4 high sink outputs (20mA)

■ 2 Timers

– Configurable watchdog timer – 8-bit timer/counter with a 7-bit prescaler

■ Analog Peripheral

– 8-bit ADC with 16 input channels

■ Instructio n Set

– 8-bit data manipulation – 40 basic instructions – 9 addressing modes – Bit manipulation

■ Development Tools

– Full hardware/software development package

Device Summary

(See Section 12.5 for Ordering Information)

PDIP28

S028

CDIP28W

SS0P28

Features

ST62T15C(OTP)

ST6215C(ROM)

ST62P15C(FASTROM)

ST62T25C(OTP)

ST6225C(ROM)

ST62P25C(FASTROM

ST62E25C(EPROM)

Program memory - bytes 2K 4K RAM - byte s 64 Operati ng S upply 3.0V to 6V Clock Fre quency 8MHz Max Operati ng T em perature -40°C to +125°C

Packages PDIP28 / S O28 / SSOP28 CDIP28 W

Table of Contents

105

2/105

1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

2 PIN DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

3 MEMORY MAPS, PROGRAMMING MODES AND OPTION BYTES . . . . . . . . . . . . . . . . . . . . . . 9

3.1 MEMORY AND REGISTER MAPS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

3.1.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

3.1.2 Program Space . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

3.1.3 Readout Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

3.1.4 Data Space . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

3.1.5 Stack Space . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

3.1.6 Data ROM Window Mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

3.2 PROGRAMMING MODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

3.2.1 Program Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

3.2.2 EPROM Erasing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

3.3 OPTION BYTES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

4 CENTRAL PROCESSING UNIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

4.1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

4.2 MAIN FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

4.3 CPU REGISTERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

5 CLOCKS, SUPPLY AND RESET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

5.1 CLOCK SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

5.1.1 Main Oscillator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

5.1.2 Oscillator Safeguard (OSG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

5.1.3 Low Frequency Au xi liary Osc illator (LFAO) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

5.1.4 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

5.2 LOW VOLTAGE DETECTOR (LVD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

5.3 RESET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

5.3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

5.3.2 RESET Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

5.3.3 RESET

Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

5.3.4 Watchdog Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

5.3.5 LVD Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

6 INTERRUPTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

6.1 INTERRUPT RULES AND PRIORITY MANAGEMENT . . . . . . . . . . . . . . . . . . . . . . . . . 29

6.2 INTERRUPTS AND LOW POWER MODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

6.3 NON MASKABLE INTERRUPT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

6.4 PERIPHERAL INTERRUPTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

6.5 EXTERNAL INTERRUPTS (I/O PORTS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

6.5.1 Notes on using External Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

6.6 INTERRUPT HANDLING PROCEDURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

6.6.1 Interrupt Response Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

6.7 REGISTER DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Table of Contents

3/105

7 POWER SAVING MODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

7.1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

7.2 WAIT MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 4

7.3 STOP MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

7.4 NOTES RELATED TO WAIT AND STOP MODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

7.4.1 Exit from Wait and Stop Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

7.4.2 Recommended MCU Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

8 I/O PORTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 8

8.1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

8.2 FUNCTIONAL DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

8.2.1 Digital Input Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

8.2.2 Analog Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

8.2.3 Output Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

8.2.4 Alternate Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

8.2.5 Instructions NOT to be used to access Port Data registers (SET, RES, INC and DEC)

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

8.2.6 Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

8.3 LOW POWER MODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

8.4 INTERRUPTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

8.5 REGISTER DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

9 ON-CHIP PERIPHERALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3

9.1 WATCHDOG TIMER (WDG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

9.1.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

9.1.2 Main Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

9.1.3 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

9.1.4 Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

9.1.5 Low Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

9.1.6 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

9.1.7 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

9.2 8-BIT TIMER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

9.2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

9.2.2 Main Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

9.2.3 Counter/Prescaler Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

9.2.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

9.2.5 Low Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

9.2.6 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

9.2.7 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

9.3 A/D CONVERTER (ADC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

9.3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

9.3.2 Main Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

9.3.3 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

9.3.4 Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

9.3.5 Low Power Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

9.3.6 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

9.3.7 Register Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

Table of Contents

105

4/105

10 INSTRUCTION SET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

10.1 ST6 ARCHITECTURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

10.2 ADDRESSING MODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

10.3 INSTRUCTION SET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

11 ELECTRICAL CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

11.1 PARAMETER CONDITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

11.1.1 M inimu m and M axim um Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

11.1.2Typical Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

11.1.3Typical Curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

11.1.4Loading Capacitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

11.1.5 Pin Input Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

11.2 ABSOLUTE MAXIMUM RATINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

11.2.1Voltage Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

11.2.2Current Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

11.2.3Thermal Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

11.3 OPERATING CONDITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

11.3.1 G eneral Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

11.3.2Operating Conditions with Low Voltage Detector (LVD) . . . . . . . . . . . . . . . . . . . . . 66

11.4 SUPPLY CURRENT CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

11.4.1RUN Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

11.4.2 W AIT Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

11.4.3STOP Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

11.4.4Supply and Clock System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

11.4.5On-Chip Peripherals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

11.5 CLOCK AND TIMING CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

11.5.1 G eneral Timings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

11.5.2External Clock Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

11.5.3Cry st al and Ceramic Resonator Oscillators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

11.5.4RC Oscillator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

11.5.5Oscillator Safeguard (OSG) and Low Frequency Auxiliary Oscillator (LFAO) . . . . . 76

11.6 MEMORY CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

11.6.1RA M and Hardware Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

11.6.2EPROM Program Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

11.7 EMC CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

11.7.1 F unct ional EMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

11.7.2Absolute Electrical Sensitivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

11.7.3ESD Pin Protection Strategy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

11.8 I/O PORT PIN CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

11.8.1General Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

11.8.2Output Driving Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

11.9 CONTROL PIN CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

11.9.1A sy nchronous RE SET Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

11.9.2NMI Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

11.10 TIMER PERIPHERAL CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

11.10.1Watchdog Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

11.10.28-Bit Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

Table of Contents

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11.11 8-BIT ADC CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

12 GENERAL INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

12.1 PACKAGE MECHANICAL DATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

12.2 THERMAL CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

12.3 SOLDERING AND GLUEABILITY INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

12.4 PACKAGE/SOCKET FOOTPRINT PROPOSAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

12.5 ORDERING INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

12.6 TRANSFER OF CUSTOMER CODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

12.6.1FASTROM Version . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

12.6.2ROM Version . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

13 DEVELOPMENT TOOLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

14 ST6 APPLICATION NOTES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

15 SUMMARY OF CHANGES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104

16 TO GET MORE INFORMATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104

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1 INTRODUCTION

The ST6215C, 25C devices are low cost members of the ST62xx 8-bit HCMOS family of microcontrollers, which is targeted at low to medium complexity applications. All ST62xx devices are based on a building block approach: a common core is surrounded by a number of on-chip peripherals.

The ST62E25C is the erasable EPROM version of the ST62T15C, T25C devices, which may be used during the development phase for the ST62T15C, T25C target devices, as well as the respective ST6215C, 25C ROM devices.

OTP and EPROM devices are functional ly identical. OTP devices offer a ll the advantages of us er programmability at low cost, which make them the ideal choice in a wide range of applications where frequent code changes, multiple c ode vers ions or last minute programmabilit y are required.

The ROM based versions offer the same functionality, selecting the options defined in the program-

mable option bytes of the OTP/EPR OM versions in the ROM option list (See Section 12.6 on page

97).

The ST62P15C/P2 5C are the Factory Advanced Service Technique ROM (FASTROM) versions of ST62T15C,T25C OTP devices.

They offer the same functionality as OTP devices, but they do not have to be programmed by the customer (See Section 12 on page 91).

These compact low -cost devices feature a Timer comprising an 8-bit counter with a 7-bit programmable prescaler, an 8-bit A/D Converter with 16 analog inputs and a Digital Wa tchdog timer, making them well suited for a wide range of automotive, appliance and industrial applications.

For easy reference, all parametric data is locat ed in Section 11 on page 63.

Figure 1. Block Diagram

NMI

INTERRUPTS

PROGRAM

STACK LEVEL 1 STACK LEVEL 2 STACK LEVEL 3 STACK LEVEL 4 STACK LEVEL 5 STACK LEVEL 6

POWER SUPPLY

OSCILLATOR

RESET

DATA RO M

USER

SELECTABLE

DATA RAM

64 Bytes

PORT A

PORT B

PORT C

TIMER

8-BIT CO RE

8-BIT

A/D CONVERTER

PA0..PA3 (20mA Sink) PA4..PA7 / Ain

PB0..PB7 / Ain

PC4..PC7 / Ain

TIMER

DDVSS

OSCin OSCout RESET

WATCHDOG

MEMORY

TIMER

(2K or 4K Bytes)

ST6215C/ST6225C

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2 PIN DESCRI PTION

Figure 2. 28-Pin Package Pinout

Table 1. Device Pin Description

28 27 26 25 24 23 22 21

1 2 3 4 5 6 7 8 9 10 11 12 13

TIMER

Ain/PB5

Ain/PB6

Ain/PB7

RESET

Ain/PC4

Ain/PC5

Ain/PC6

Ain/PC7

NMI

OSCout

OSCin

PA0/20mA Sink

PB4/Ain

PB3/Ain

PB2/Ain

PB1/Ain

PB0/Ain

PA7/Ain

PA6/Ain

PA5/Ain

PA4/Ain

PA3/20mA Sink

PA2/20mA Sink

PA1/20mA Sink

it2

it1

it2

itX associated interrupt vector

it2

Pin n° Pin Name

Type

Main Function

(after Reset)

Alternate Function

1 V

S Main power supply

TIMER

I/O Timer input or output 3 OSCin I External clock input or resonator oscillator inverter input 4 OSCout O Resonator oscillator inverter output or resistor input for RC oscillator 5 NMI I Non maskable interrupt (falling edge sensitive) 6 PC7/Ain I/O Pin C7 (IPU) Analog input 7 PC6/Ain I/O Pin C6 (IPU) Analog input 8 PC5/Ain I/O Pin C5 (IPU) Analog input 9 PC4/Ain I/O Pin C4 (IPU) Analog input

10 V

Must be held at Vss for normal operation, if a 12.5V level is applied to the pin during the reset phase, the device enters EPROM programming mode.

11 RESET

I/O Top priority non maskable interrupt (active low) 12 PB7/Ain I/O Pin B7 (IPU) Analog input 13 PB6/Ain I/O Pin B6 (IPU) Analog input

ST6215C/ST6225C

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Legend / Abbreviations for Table 1:

I = input, O = output, S = supply, IPU = input pull-up The input with pull-up configuration (reset state) is valid as long as the user software does not change it. Refer to Section 8 "I/O PORTS" on page 38 for more details on the software configuration of the I/O ports.

14 PB5/Ain I/O Pin B5 (IPU) Analog input 15 PB4/Ain I/O Pin B4 (IPU) Analog input 16 PB3/Ain I/O Pin B3 (IPU) Analog input 17 PB2/Ain I/O Pin B2 (IPU) Analog input 18 PB1/Ain I/O Pin B1 (IPU) Analog input 19 PB0/Ain I/O Pin B0 (IPU) Analog input 20 PA7/Ain I/O Pin A7 (IPU) Analog input 21 PA6/Ain I/O Pin A6 (IPU) Analog input 22 PA5/Ain I/O Pin A5 (IPU) Analog input 23 PA4/Ain I/O Pin A4 (IPU) Analog input 24 PA3/ 20mA Sink I/O Pin A3 (IPU) 25 PA2/ 20mA Sink I/O Pin A2 (IPU) 26 PA1/ 20mA Sink I/O Pin A1 (IPU) 27 PA0/ 20mA Sink I/O Pin A0 (IPU) 28 V

S Ground

Pin n° Pin Name

Type

Main Function

(after Reset)

Alternate Function

ST6215C/ST6225C

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3 MEMORY MAPS, PROGRAMMING MODES AND OPTION BYTES

3.1 MEMORY AND REGISTER MAPS

3.1.1 Introd uct i on

The MCU operates in three separate memory spaces: Program space, Data space, and Stack space. Operation in these three memory spaces is described in the following paragraphs.

Briefly, Program space contains user program code in OTP and user vectors; Data space contains user data in RAM and in OTP, and Stack space accommodat es six levels of stack for subroutine and interrupt service routine nesting.

Figure 3. Mem ory Addressing Dia gram

PROGRAM SPACE

PROGRAM

INTERRUPT &

RESET VECTORS

ACCUMULATOR

RAM

X REGISTER Y REGISTER V REGISTER

W REGISTER

000h

03Fh 040h

07Fh 080h 081h 082h 083h 084h

0C0h

0FFh

DATA SPACE

000h

0FF0h

0FFFh

MEMORY

MEMORY WINDOW

DATA READ-ONLY

RESERVED

HARDWARE

CONTROL

REGISTERS

0BFh

(see Table 2)

(see Figure 4

on page 10)

ST6215C/ST6225C

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MEMORY MAP (Cont’d) Figure 4. Program Memory Map

RESERVED

0000h

07FFh 0800h

087Fh

NOT IMPLEMENTED

RESERVED

USER

PROGRAM MEMORY

1824 BYTES

0880h

0F9Fh 0FA0h 0FEFh 0FF0h 0FF7h 0FF8h 0FFBh 0FFCh 0FFDh 0FFEh 0FFFh

RESERVED

INTE RR U PT VECTOR S

NMI VECTOR

USER RESET VECTOR

(*) Reserved areas should be filled with 0FFh

0000h

07Fh

USER

PROGRAM ME M OR Y

3872 BYTES

080h

0F9Fh 0FA0h

0FEFh

0FF0h 0FF7h

0FF8h 0FFBh 0FFCh 0FFDh 0FFEh

0FFFh

RESERVED

INTERRUPT VECTORS

NMI VECTOR

USER RESET VECTOR

RESERVED

ST6215C ST6225C

ST6215C/ST6225C

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MEMORY MAP (Cont’d)

3.1.2 Program Space

Program Space comprises the instructions to b e executed, the data required for immediate addressing mode instructions, the reserved factory test area and the user v ectors. Program Space is addressed via the 12-bit Program Counter register (PC register). Thus, the MCU is capable of addressing 4K bytes of memory directly.

3.1.3 Readout Protection

The Program Mem ory i n O TP or E P ROM devices can be protected against external readout of memory by setting the Readout Protection bit in the opti on byte (Section 3.3 on page 16).

In the EPROM parts, Readout Protection option can be desactivated only by U.V. erasure that also results in the whole EPROM context being erased.

Note: Once the Readout Protection is activated, it is no longer possible, even for STMicroelectronics, to gain access to the OTP contents. Returned parts can therefore not be accepted if the Readout Protection bit is set.

3.1.4 Data Space

Data Space accommodates all the data necessary for processing the user program. This space comprises the RAM resource, the proc essor core an d peripheral registers, as well as read-only data

such as constants and look-up tables in OTP/ EPROM.

3.1.4.1 Data ROM

All read-only data is physically stored in program memory, which also accommodates the Program Space. The program m emory consequently contains the program code to be executed, as well as the constants and look-up tables required by t he application.

The Data Space locations in which the different constants and look-up tables are addressed by the processor core may be thought of as a 64-byte window through which it is possible to acc ess the read-only data stored in OTP/EPROM.

3.1.4.2 Data RAM

The data space includes the user RAM area, the accumulator (A), the indirect registers (X), (Y), the short direct registers (V), (W), the I/O port registers, the peripheral data and control registers, the interrupt option register and the Data ROM Window register (DRWR register).

3.1.5 Stack Space

Stack space consists of six 12-bit registers which are used to stack subroutine and interrupt return addresses, as well as the current program counter contents.

ST6215C/ST6225C

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MEMORY MAP (Cont’d) Table 2. Hardware Register Map

Legend:

x = undefined, R/W = Read/Write, Ro = Read-only Bit(s) in the register, Wo = Write-only Bit(s) in the register.

Notes:

1. The contents of the I/O p ort D R registers are read able only in output configuration. In i nput c onfiguration, the values of the I/O pins are returned instead of the DR register contents.

2. The bits associated with unavailable pins must always be kept at their reset value.

3. Do not use single-bit instructions (SET, RES...) on Port Data Registers if any pin of the port is configured in input mode (refer to Section 8 "I/O PORTS" on page 38 for more details).

Address Block

Label

Reset

Status

Remarks

080h

to 083h

CPU X,Y,V,W

X,Y index registers V,W short direct registers

xxh R/W

0C0h 0C1h 0C2h

I/O Ports

DRA

1) 2) 3)

DRB

1) 2) 3)

DRC

1) 2) 3)

Port A Data Register Port B Data Register Port C Data Register

00h 00h 00h

R/W R/W

R/W 0C3h Reserved (1 Byte) 0C4h

0C5h 0C6h

I/O Ports

DDRA

DDRB

DDRC

Port A Direction Register Port B Direction Register Port C Direction Register

00h 00h 00h

R/W

R/W 0C7h Reserved (1 Byte) 0C8h CPU IOR Interrupt Option Register xxh Write-only 0C9h ROM DRWR Data ROM Window register xxh Write-only 0CAh

0CBh

Reserved (2 Bytes)

0CCh 0CDh 0CEh

I/O Ports

ORA

ORB

ORC

Port A Option Register Port B Option Register Port C Option Register

00h 00h 00h

R/W

0CFh Reserved (1 byte)

0D0h 0D1h

ADC

ADR ADCR

A/D Converter Data Register A/D Converter Control Register

xxh 40h

Read-only

Ro/Wo 0D2h

0D3h 0D4h

Timer1

PSCR TCR TSCR

Timer 1 Prescaler Register Timer 1 Counter Register Timer 1 Status Control Register

7Fh

0FFh

00h

R/W

R/W 0D5h

to 0D7h

Reserved (3 Bytes)

0D8h

Watchdog

Timer

WDGR Watchdog Register 0FEh R/W

0D9h

to 0FEh

Reserved (38 Bytes)

0FFh CPU A Accumulator xxh R/W

ST6215C/ST6225C

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MEMORY MAP (Cont’d)

3.1.6 Data ROM Window Mechanism

The Data read-only memory window is located from address 0040h to address 007Fh in Data space. It allows direct reading of 64 consecutive bytes located anywhere in program memory, between address 0000h and 0FFFh.

There are 64 blocks of 64 bytes in a 4K device: – Block 0 is related to the address range 0000h to

003Fh.

– Block 1 is related to the address range 0040h to

007Fh. and so on... All the program memory can therefore be used to

store either instructions or read-only data. The Data ROM window can be moved in st eps of 64 bytes along the program memory by writing the appropriate code in the Data ROM Window Register (DRWR).

Figure 5. Data R OM Window

3.1.6.1 Data ROM Window Register (DRWR)

The DRWR can be a ddressed li ke any RAM location in the Data Space.

This register is used to sele ct the 64-byt e blo ck of program memory to be read in the Data ROM window (from address 40h to address 7Fh in Data space). The DRWR register is not clea red on reset, therefore it must be written to before accessing the Data read-on ly memory window area for the first time .

Address: 0C9h — Write Only Reset Value = xxh (undefined)

Bits 7:6 = Reserved, must be cleared.

Bits 5:0 = DRWR[5:0]

Data read-only memory

Window Register Bits.

These are the Data readonly memory Window bits that correspond to the upper bits of the data read-only memory space.

Caution:

This register is undefined on reset, it is write-only, therefore do not read it nor access it using Read-Modify-Write instructions (SET, RES, INC and DEC).

0000h

0FFFh

000h

040h

07Fh

0FFh

DATA ROM

WINDOW

DATA SPACE

64-BYTE

ROM

PROGRAM

SPACE

- - DRWR5 DRWR4 DRWR3 DRWR2 DRWR1 DRWR0

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MEMORY MAP (Cont’d)

3.1.6.2 Data ROM Window memory addressing

In cases where some data (look-up tables for example) are stored in program memory, reading these data requires the use of the Data ROM window mechanism. To do this:

1. The DRWR register ha s to be loaded with the 64-byte block number where the data are located (in program memory). This number also gives the start address of the block.

2. Then, the offset address of the byte in th e Data ROM Window (corresponding to the offset in the 64-byte block in program memory) has to be loaded in a register (A, X,...).

When the above two steps are completed, the data can be read.

To understand how to determine the DRWR and the content of th e register, please refer to t he example shown in Figure 6. I n any c ase t he c alcul a-

tion is automatically hand led by the ST6 deve lopment tools.

Please refer to the user manual of the corres poding tool.

3.1.6.3 Recommendations

Care is required when handling the DRWR register as it is write only. For this reason, the DRWR contents should not be chan ged while executing an interrupt service routine, as the service routine cannot save and then restore the register’s previous contents. If it is imp ossible to avoi d writing to the DRWR during the interrupt service routine, an image of the register must be saved in a RAM location, and each time the program writes to the DRWR, it must also write to the image register. The image register must be written first so that, if an interrupt occurs between the two instructions, the DRWR is not affected.

Figure 6. Data read-only memory Window Memo ry Add ressi ng

DATA

PROGRAM SPACE

DATA SPACE

0000h

0400h

0421h

07FFh

64 bytes

OFFSET

000h

040h

061h 07Fh

OFFSET 21h

0FFh

DRWR

DATA address in Program memory : 421h DRWR content : 421h / 3Fh (64) = 10H data is located in 64-bytes window number 10h 64-byte window start address : 10h x 3Fh = 400h Register (A, X,...)content : Offset = (421h - 400h) + 40h ( Data ROM Window start address in data space) = 61h

10h

DATA

ST6215C/ST6225C

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3.2 PROGRAMMING MODES

3.2.1 Program Memory

EPROM/OTP programming mode is set by a +12.5V voltage a pplied to the T EST/V

pin. The programming flow of the ST62T15C,T25C/E25C is described in the User Manual of the EPROM Programming Board.

Table 3. ST6215C Program Memo ry M ap

Table 4. ST6225C Program Memo ry M ap

Note: OTP/EPROM devices can be programm ed

with the development tools available from STMicroelectronics (please refer to Section 13 on

page 100).

3.2.2 EPROM Erasing

The EPROM devices can be erased by exposure to Ultra Violet light. The characteristics of the MCU are such that erasure begins when the memory is exposed to light with a wave lengths shorter than

approximately 4000Å. It should be noted that sunlight and some types of fluorescent lamps have wavelengths in the range 3000-4000Å.

It is thus recommended that the window of the MCU packages be covered by an opaque label to prevent unintentional erasure problems when testing the application in such an environment.

The recommended erasure procedure is exposure to short wave u ltraviolet light whi ch have a wavelength 2537Å. The integrated dose (i.e. U.V. intensity x exposure time) for erasure should be a minimum of 30W-sec/cm

. The erasure time with this dosage is approximately 30 to 40 minutes using an ultraviolet lamp with 12000µW/cm

power rating.

The EPROM device should be placed within

2.5cm (1inch) of the lamp tubes during erasure.

Device Address Description

0000h-087F h 0880h-0F9F h

0FA0h-0FEF h

0FF0h-0FF7 h

0FF8h-0FFB h

0FFCh-0FFD h

0FFEh-0FFF h

Reserved

User ROM

Reserved

Interrupt Vectors

Reserved

NMI Interrupt Vector

Reset Vector

Device Address Description

0000h-007F h

0080h-0F9F h

0FA0h-0FEF h

0FF0h-0FF7 h

0FF8h-0FFB h

0FFCh-0FFD h

0FFEh-0FFF h

Reserved

User ROM

Reserved

Interrupt Vectors

Reserved

NMI Interrupt Vector

Reset Vector

ST6215C/ST6225C

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3.3 OPTION BYTES

Each device is available for production in user programmable versions (OTP) as well as in factory coded versions (ROM). O TP d evices are shippe d to customers with a default content (00h), while ROM factory coded parts contain the code supplied by the customer. This implies that OTP devices have to be configured by the customer using the Option Bytes while the ROM devices are factory-configured.

The two option b ytes allow t he hardware configuration of the microcontroller to be selected. The option bytes have no address in the memory map and can be accessed only in programming mode (for example using a standard ST6 programming tool). In masked ROM devices, the option bytes are fixed in hardware by the ROM code (see Section

12.6.2 "ROM Versio n" on page 98 ). It is therefore

impossible to read the option bytes. The option bytes can be only programmed once. It

is not possible to change the selected options after they have been programmed.

In order to reach the power consumption value indicated in Section 11.4, the option byte must be programmed to its default value. Otherwise, an over-consumption will occur.

MSB OPTION BY TE

Bits 15:10 = Reserved, must be always cleared.

Bit 9 = EXTCNTL

External STO P MO DE control.

0: EXTCNTL mode not available. STOP mode is

not available with the watchdog active.

1: EXTCNTL mode available. STOP mode is avail-

able with the watchdog active by setting NMI pin to one.

Bit 8 = LVD

Low Voltage Detector

on/off

This option bit enable or disable the Low Voltage Dete ctor (LVD ) feature.

0: Low Voltage Detector disabled 1: Low Voltage Detector enabled.

LSB OPTION BYTE

Bit 7 = PROTECT

Readout Protection.

This option bit enables or disables external access to the internal program memory. 0: Program memory not read-out protected 1: Program memory read-out protected

Bit 6 = OSC

Oscillator s elec tion

. This option bit selects the main oscillator type. 0: Quartz crystal, ceramic resonator or external

clock

1: RC network

Bits 5:4 = Reserved, must be always cleared.

Bit 3 = NMI PULL

NMI Pull-Up

on/off. This option bit enables or disables the internal pullup on the NMI pin. 0: Pull-up disabled 1: Pull-up enabled

Bit 2 = TIM PULL

TIMER Pull-Up

on/off. This option bit enables or disables the internal pullup on the TIMER pin. 0: Pull-up disabled 1: Pull-up enabled

Bit 1 = WDACT

Hardware or software watchdog.

This option bit selects the watchdog type. 0: Software (watchdog to be enabled by software) 1: Hardware (watchdog always enabled)

Bit 0 = OSGEN

Oscillator Safeguard

on/off. This option bit enables or disables the oscillator Safeguard (OSG) feature. 0: Oscillator Safeguard disabled 1: Oscillator Safeguard enabled

MSB OPTION BYTE

15 8

LSB OPTION BYTE

Reserved

EXT CTL

LVD

PRO-

TECT

OSC Res. Res.

NMI

PULL

TIM

PULLWDACT

OSG

Default

Value

XXXXXXXXXXXXX X X X

ST6215C/ST6225C

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4 CENTRAL PROCE SSI NG UNIT

4.1 INTRODUCTION

The CPU Core of ST6 devices is independent of the I/O or Memory conf iguration. As such, it may b e thought of as an independent central processor communicating with on-chip I/O, Memory and Peripherals via internal address, data, and control buses.

4.2 MAIN FEATURES

■ 40 basic instructions

■ 9 main addressing modes

■ Two 8-bit index registers

■ Two 8-bit short direct registers

■ Low power modes

■ Maskable hardware interrupts

■ 6-level hardware stack

4.3 CPU REGISTERS

The ST6 Family CPU core features six registers and three pairs of flags available to the programmer. These are described in the following paragraphs.

Accumulator (A). The accumulator is an 8-bit general purpose register used in all arithmetic calculations, logical operations, and data manipula-

tions. The accumulator can be addressed i n Data Space as a RAM lo cation at address FFh. Thus the ST6 can manipulate the accumulator just like any other register in Data Space.

Index Registers (X, Y). Th ese two registers are used in Indirect addressing mode as pointers to memory locations in Data Space. They can also be accessed in Direct, Short Direct, or Bi t Direct addressing modes. They are mapped in Data Space at addresses 80h (X ) and 81h (Y) an d can be accessed like any other memory location.

Short Direct Registers (V, W). These two registers are used in Short Direct addressing mode. This means that the data stored in V or W can be accessed with a one-byte instruction (four CPU cycles). V and W can also be accessed using Di rect and Bit Direct addressing modes. They are mapped in Data Space at addresses 82h (V) and 83h (W) and can be accessed like any other memory location.

Note: The X and Y registers can also be used as Short Direct registers in the same way as V and W.

Program Counter (PC). The program counter is a 12-bit register which cont ains the address of the next instruction to be executed by the c ore. This ROM location may be an opc ode, an operand, or the address of an operand.

Figure 7. CPU Registers

ACCUMULA T OR

X INDEX REGISTER

Y INDEX REGISTER

PROGRAM COUNTER

RESET VALUE = RESET VECTOR @ 0FFEh-0FFFh

RESET VALUE = xxh

x = Undefined value

V SHORT INDIRECT

RESET VALUE = xxh

W SHORT INDIRECT

RESET VALUE = xxh

NORMAL FLAGS

CN ZN

CI ZI

CNMI ZNMI

INTERRUPT FLAGS

NMI FLAGS

SIX LEVEL

STACK

ST6215C/ST6225C

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CPU REGISTERS (Cont’d) The 12-bit length allows the direct addressing of

4096 bytes in Program Space. However, if the program space contains more than

4096 bytes, the additional memory in program space can be addressed by using the Program ROM Page register.

The PC value is incremented after reading the address of the current instruction. To execute relative jumps, the PC and the offset are shifted through the ALU, where they are added; the result is then shifted back into the PC. The program counter can be changed in the following ways:

– JP (Jump) instruction PC = Jump address – CALL instruction PC = Call address – Relative Branch InstructionPC = PC +/- offset – Interrupt PC = Interrupt vector – Reset PC = Reset vector – RET & RETI instructions PC = Pop (stack) – Normal instruction PC = PC + 1 Flags (C, Z). The ST6 CPU includes three pairs of

flags (Carry and Zero), each pair being associated with one of the three normal modes of operation: Normal mode, Interrupt mode and Non Maskabl e Interrupt mode. Each pair consists of a CARRY flag and a ZERO flag. One pair (CN, ZN) is u sed during Normal operation, another pair is used during Interrupt mode (CI, ZI), and a third pair is used in the Non Maskable Interrupt m ode (CNMI, ZNMI).

The ST6 CPU uses the pair of flags associated with the current mode: as soon as an interrupt (or a Non Maskable I nterrupt) is generated, the ST 6 CPU uses the Interrupt flags (or the NMI flag s) instead of the Normal flags. When the RETI instruction is executed, the previously used set of flags is restored. It should be noted that ea ch flag s et can only be addressed in its own context (Non Maskable Interrupt, Normal Interrupt or Main routine). The flags are not cleared during context swi tching and thus retain their status.

C : Carry flag. This bit is set when a carry or a borrow occurs dur-

ing arithmetic operations; otherwise it is cleared. The Carry flag is also set to the val ue of the bit tested in a bit test instruction; it also participates in the rotate left instruction. 0: No carry has occured 1: A carry has occured

Z : Zero flag This flag is set if the result of the last arithmetic or logical operation was equal to zero; otherwise it is cleared. 0: The result of the last operation is different from

zero

1: The result of the last operation is zero Switching between the three sets of flags is per-

formed automatically when an NMI, an interrupt or a RETI instruction occurs. As NMI mode is automatically selected after the reset of the MCU, the ST6 core uses the NMI flags first.

Stack. The ST6 CPU includes a true LIFO (Last In First Out) hardware stack which eliminates the need for a stack pointer. The stack consists of six separate 12-bit RAM locations that do not belong to the data space RAM area. When a subroutine call (or interrupt request) oc curs, the contents of each level are shifted into the next level down, while the content of the PC is shifted into the first level (the original contents of the sixth stack level are lost). When a subroutine or interrupt return occurs (RET or RETI instructions), the first level register is shifted back into the PC and the value of each level is popped back into the previous level.

Figure 8. Stack manipulation

Since the accumulator, in common with all other data space registers, is not stored in this stack, management of these registers should be performed within the subroutine.

Caution: The stack will remain in its “deepest” position if more than 6 nested calls or interrupts are executed, and consequently the last return address will be lost.

It will also remain in its highest position if the stack is empty and a RET or RETI is executed. In this case the nex t in s truc t io n w ill be ex e c ut e d.

LEVEL 1 LEVEL 2 LEVEL 3 LEVEL 4 LEVEL 5 LEVEL 6

ON INTERRUPT, OR SUBROUTINE CALL

ON RETURN FROM INTERRUPT, OR SUBROUTINE

PROGRAM

COUNTER

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5 CLOCKS, SUPPLY AND RESET

5.1 CLOCK SYSTEM

The main oscillator of the MCU can be driven by any of these cl ock sourc es:

– external clock signal – external AT-cut parallel-resonant crystal – external ceramic resonator – external RC network (R

NET

In addition, an on-chip Low Frequency Auxiliary Oscillator (LFAO) is available as a back-up c lock system or to reduce power consumption.

An optional Oscillator Safeguard (OSG) filters spikes from the oscillator lines, and switches to the LFAO backup oscillator in t he event of m ain oscillator failure. It also automatically limits the internal clock frequency (f

INT

) as a function of VDD, in order to guarantee correct operation. These functions are illustrated in Figure 10, and F igure 11.

Table 5 illustrat es var ious poss ible os cillator c on-

figurations using an external crystal or ceramic resonator, an external clock input, an external resistor (R

NET

), or the lowest cost solution using only

the LFAO. For more details on c onfiguring the c lock options,

refer to the Option Bytes section of this document. The internal MCU clock frequency (f

INT

) is divided by 12 to drive the T imer, the Wat chdog timer and the A/D converter, by 13 to drive the CPU core and the SPI and by 1 or 3 to drive the ARTIMER, as shown in Figure 9.

With an 8 M Hz o s c illat o r, the fastes t CP U cycle is therefore 1.625µs.

A CPU cycle is the smallest unit of time needed to execute any operation (f or instance, to increment the Program Counter). An instruction may require two, four, or five CPU cycles for execution.

Figure 9. Clock Circuit Block Diagram

MAIN

OSCILLATOR

OSG

LFAO

CORE

8-BIT TIMER

WATCHDOG

INT

OSCOFF BIT

ADC

filtering

OSCILLATOR SAFEGUA RD (OSG)

OSG ENABLE OPTION BIT (See OPTION BYTE SECTION)

(ADCR REGISTER)

OSC

Oscillator Divider

SPI

: 1

: 3

8-BIT ARTIMER

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CLOCK SYSTEM (Cont’d)

5.1.1 Main Oscillator

The oscillator configuration is specified by selecting the appropriate option in the option bytes (refer to the Option Bytes section of this document). When the CRYSTAL/RESONATOR option is selected, it must be used with a quartz crystal, a ceramic resonator or an external signal provided on the OSCin pin. When the RC NETWORK option is selected, the system clock is generated by an external resistor (the capacitor is imple men ted internally).

The main oscillator can be turned off (when the OSG ENABLED option is selected) by setting the OSCOFF bit of the ADC Control Register (not available on some devices). This will automatically start the Low Frequency Auxiliary Oscillator (LFAO).

The main oscillator can be turned off by resetting the OSCOFF bit of the A/D Converter Control Register or by resetting the MCU. When the main oscillator starts there is a delay made up of the oscillator start-up delay period plus the duration of the software instruction at a clock frequency f

LFAO

Caution: It should be noted that when t he RC network option is selected, the accuracy of the frequency is about 20% so it may not be suitable for some applications (For more details, please refer to the Electrical Characteristics Section).

Table 5. Oscillator Configurations

Notes:

1. To select the options sho wn in column 1 of the abo ve table, refer to the Option Byte section.

2.This schematic are given for guidance only and are subject to the schematics given by the crystal or ceramic resonator manufacturer.

3. For more details, plea se refer to the Electric al Char acteristics Section.

Hardware Configuration

Crystal/Resonator Option

RC Network Option

OSG Enabled Option

OSCin OSCout

EXTERNAL

ST6

CLOCK

External Clock

OSCin OSCout

LOAD

CAPACITORS

ST6

Crystal/Resonator Clock

OSCin OSCout

ST6

NET

RC Network

OSCin OSCout

ST6

LFAO

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CLOCK SYSTEM (Cont’d)

5.1.2 Oscillator Safeguard (OSG)

The Oscillator Safeguard (OSG) feature is a means of dramatically improving the operational integrity of the MCU. It is available when the OSG ENABLED option is selected in the option byte (refer to the Option Bytes section of this document).

The OSG acts as a filter whose cross-over frequency is device dependent and provides three basic functions:

– F iltering spikes o n the os c illator lines whic h

would result in driving the CPU at excessive frequencies

– M anag ement of the Low Frequency Auxiliar y

Oscillator (LFAO), (useable as low cost internal clock source , backup clock i n ca se of main oscillator failure or for low power consumption)

– Automatically limiting the f

INT

clock frequency as a function of supply voltage, to ensure correct operation even if the power supply drops.

5.1.2.1 Spike Filtering

Spikes on the oscillator lines result in an effectively increased internal clock frequency. In the absence of an OSG circuit, this may lead to an over frequency for a given power supply voltage. The OSG filters out such spikes (as illustrated in Figure

10). In all cases, when the OSG is active, the max-

imum internal clock frequency, f

INT

, is limited to

OSG

, which is supply voltage dependent.

5.1.2.2 Management of Supply Voltage Variations

Over-frequency, at a given power supp ly level, is seen by the OSG as spikes; it therefore filte rs out some cycles in order that the internal clock frequency of the device is kept within the range t he particular device can stand (depending o n V

and below f

OSG

: the maximum authorised frequen-

cy with OSG enabled.

5.1.2.3 LFAO Managemen t

When the OSG is enabled, the Low Frequency Auxiliary Oscillator can be used (see Section

5.1.3).

Note: The OSG should be used wherever possible as it provides maxim um security for the ap plication. It should be noted however, that it can increase power consumption and reduce the maximum operating frequency to f

OSG

(see Electrical

Characteristics section). Caution: Care has to be taken when using the

OSG, as the internal frequency is defined between a minimum and a maximum value and may vary depending on both V

and temperature. For precise timing measurement s, it is not recom men ded to use the OSG.

Figure 10. OSG Filtering Function

Figure 11. LFAO Oscillato r Function

OSC

OSG

INT

OSC<fOSG

OSC>fOSG

MAIN OSCILLATOR STOPS

MAIN OSCILLA T OR

RESTARTS

INTERNAL CLOCK DRIVEN BY LFAO

OSC

INT

LFAO

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CLOCK SYSTEM (Cont’d)

5.1.3 Low Frequency Auxiliary Oscillator (LFAO)

The Low Frequency Auxiliary Oscillator has three main purposes. Firstly, it can be used to reduce power consumption in non timing critical routines. Secondly, it offers a fully integrated system clock, without any external components. Lastly, it acts as a backup oscillator in case of m ain oscillator failure.

This oscillator is available when the OSG ENABLED option is selected in the option byte (refer to the Option Bytes section of this document). In this case, it automatically starts one of its periods after the first missing edge of t he m ain os cillator, whatever the reason for the failure (main oscillator defective, no clock circuit ry prov i ded, m ain o scillat or switched off...). See Figure 11.

User code, normal interrupts, WAIT and STOP instructions, are processed as normal, at the reduced f

LFAO

frequency. The A/D converter accuracy is decreased, since the internal frequency is below 1.2 MHz .

At power on, until the main oscillator starts, the reset delay counter is driven by the LFAO. If the main oscillator starts before the 2048 or 32768 cycle delay has elapsed, it takes over.

The Low Frequency Auxiliary Oscillator is automatically switched off as soon as the main oscillator starts.

5.1.4 Register Description ADC CONTROL REGISTER (ADCR)

Address: 0D1h — Read/Write Reset value: 0100 0000 (40h)

Bit 7:3, 1:0 = ADCR[7:3], ADCR[1:0]

ADC Control

These bits are used to control the A/D converter (if available on the device) otherwise they are not used.

Bit 2 = OSCOFF

Main Oscillator Off.

0: Main oscillator enabled 1: Main oscillator disabled

Note: The OSG must be enabled using the OSGEN option in the Opt ion Byte, otherw ise t he OSCOFF setting has no effect.

ADCR7ADCR6ADCR5ADCR4ADCR3OSC

OFF

ADCR1ADCR

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5.2 LOW VOLTAGE DETECTOR (LVD)

The on-chip Low Voltage De tector is enabled by setting a bit in the option bytes (refer to the Option Bytes section of this document).

The LVD allows the device to be used without any external RESET circuitry. In this ca se , th e RESET pin should be left unconnected.

If the LVD is not used, an external circuit is mandatory to ensure correct Power On R eset operation, see figure in the Reset section. For more details, please refer to the application note AN669.

The LVD generates a static Reset when the supply voltage is below a reference value. This means that it secures the power-up as well as the powerdown keeping the ST6 in reset.

The V

IT-

reference value for a voltage drop is lower

than the V

IT+

reference value for power-on in order to avoid a parasitic reset when the MCU starts running and sinks current on the supply (hysteresis).

The LVD Reset circuitry gene rates a reset when V

is below:

– V

IT+

when VDD is rising

– V

IT-

when VDD is falling The LVD function is illustrated in Figu re 12. If the LVD is enabled, the MCU can be in only one

of two states: – Over the input threshold voltage, it is running un-

der full software control

– Below the input threshold voltage, it is in static

safe reset

In these conditions, secure operation is guaranteed without the need for external reset hardware.

During a Low Voltage Detector Reset, the RESET pin is held low, thus p ermitting the MCU to reset other devices.

Figure 12. Low Voltage Detector Reset

IT+

RESET

IT-

hyst

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5.3 RESET

5.3.1 Introd uction

The MCU can be reset in three ways:

■ A low pulse input on the RESET pin

■ Internal Watchdog reset

■ Internal Low Voltage Detector (LVD) reset

5.3.2 RESET Sequence

The basic RESET sequence consists of 3 main phases:

■ Internal (watchdog or LVD) or external Reset

event

■ A delay of 2048 or 32768 clock (f

INT

) cycles

(selected through the option bytes)

■ RESET vector fetch

The reset delay allows the oscillator to stabilise and ensures that recovery ha s taken place from the Reset state.

The RESET vector fetch phase duration is 2 clock cycles.

When a reset occurs:

– The stack is cleared – The PC is loaded with the address of the Reset

vector. It is located in program ROM starting at address 0FFEh.

A jump to the beginning of the us er program m ust be coded at this address.

– The interrupt flag is automatically set, so that the

CPU is in Non Maskable Interrupt mode. This prevents the initialization routine from being interrupted. The initialization routine should therefore be terminated by a RETI instruction, in order to go back to normal mode.

Figure 13. RESET Sequence

RESET PIN

WATCHDOG

IT+

IT-

WATCHDOG UNDERFLOW

RESET

2048 CLOCK CYCLE (f

INT

) DELAY

LVD

RESET

INTERNAL

RUN

RESET

RUN RUN RUN

RESET RESET

RESET

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RESET (Cont’d)

5.3.3 RESET

The RESET

pin may be co nnecte d to a device on the application board in order to reset the MCU if required. The RESET

pin may be pulled low in RUN, WAIT or STOP mode. This input can be used to reset the internal state of the MCU and ensure it starts-up correctly. The pin, which i s connected to an internal pull-up, is active low and features a Schmitt trigger input. A delay (2048 clock cycles) added to the external signal ensures that even short pulses on the RESET

pin are accepted

as valid, provided V

has completed its rising phase and that the oscillator is running correctly (normal RUN or WAIT modes). The MCU is kept in the Reset state as long a s the RESET

pin is held

low.

If the RESET

pin is grounded while the MCU is in RUN or WAIT modes, processing of the user program is stopped (RUN mode only), the I/O ports are configured as inputs with pull-up resistors and the main oscillator is restarted. When the level on the RESET

pin then goes high, the initialization sequence is executed at the end of the internal delay period.

If the RESET

pin is grounded while the MCU is in STOP mode, the oscillator starts up and all the I/O ports are configured as inputs with pull-up resistors. When the RESET

pin level then go es high, the initialization sequence is executed at th e end of the internal delay period.

A simple external RESET circuitry is shown in Fig-

ure 15. For more details, please refer to the appli-

cation note AN669.

Figure 14. Reset Block Diagram

IN T

COUNTER

RESET

WATCHDOG RESET

LVD RESET

INTERNAL

RESET

ESD

1) Resistive ESD protection.

2048 or 32768

clock cycles

2) The reset delay value is selected through the option bytes.

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RESET (Cont’d)

5.3.4 Watchdog Reset

The MCU provides a Wat chdog timer function in order to be able to recover from software hangups. If the Watchdog register is not refreshed before an end-of-count condition is reached, a Watchdog reset is generated.

After a Watchdo g reset, the MCU resta rts in the same way as if a Reset was generated by the RESET pin.

Note: When a watchdog reset occurs, the RESET pin is tied low for very short time period, to flag the reset phase. This time is n ot long enough to reset external circuits.

For more details refer to the Watchdog Timer chapter.

5.3.5 LVD Reset

Two different RESET sequences caused by the internal LVD circuitry can be distinguished:

■ Power-On RESET

■ Voltage Drop RESET

During an LVD reset, the RESET

pin is pulled low

when V

IT+

(rising edge) or VDD<V

IT-

(falling

edge). For more details, refer to the LVD chapter. Caution: Do not externally connect directly the

RESET

pin to VDD, this may cause damage to the component in case of internal RESET (Watchdog or LVD).

Figure 15. Simple External Reset Circuitry

Figure 16. Reset Processing

ST62xx

RESET

Typical: R = 10K

C = 10nF

R > 4.7 K

INT LATCH CLEARED

NMI MASK SET

(IF PRESENT)

SELECT

NMI MODE FLA G S

IS RESET STILL

PRESENT?

YES

PUT FFEh

ON ADDRESS BUS

FROM RESET LOCATIONS

FFEh/FFFh

FETCH INSTRUCTION

LOAD PC

INTERNAL

RESET

2048 OR 327 68 CLOCK CYC LE

DELAY

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6 INTE RRUPTS

The ST6 core may be interrupted by four maskable interrupt sources, in addition to a Non Maskable Interrupt (NMI) source. The interrupt processing flowchart is shown in Figure 18.

Maskable interrupts must be enabled by setting the GEN bit in the IOR register. However, even if they are disabled (GEN bit = 0 ), interrupt events are latched and may be processed as soon as the GEN bit is set.

Each source is associated with a specific Interrupt Vector, located in Program space (see Interrupt

Mapping table). In the vector location, the user

must write a Jump instruction to the associated interrupt service routine.

When an interrupt source generates an i nterrupt request, the PC register is loaded with the address of the interrupt vector, which then causes a Jum p to the relevant interrupt service routine, thus servicing the int e r ru pt.

Interrupts are triggered by events either on external pins, or from the on-chip periphe rals. Several events can be ORed on the same interrupt vector. On-chip peripherals have flag registers to determine which event triggered the interrupt.

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Figure 17. Interrupts Block Diagram

NMI

ESB BIT

LATCH

CLEARED BY H/W

AT START OF VECTOR #0 ROUTINE

VECTOR #0

LES BIT

LATCH

CLEARED BY H/W AT START OF

VECTOR #1

VECTOR #2

VECTOR #3

VECTOR #4

LATCH

CLEARED BY H/W AT START OF VECTOR #2 ROUTINE

I/O PORT REGISTER

CONFIGURATION

“INPUT WITH INTER RUP T”

I/O PORT REGISTER CONFIGURATION

“INPUT WITH INTER RUP T”

EXIT FROM STOP/WAIT

VECTOR # 1 ROUTINE

TIMER

A/D CONVERTER

TMZ BIT

ETI BIT

EAI BIT

EOC BIT

GEN BIT

PB0..PB7

PA0..PA7

(TSCR REGISTER)

(ADCR REG I ST ER)

(IOR REGISTER)

PC4..PC7

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6.1 INTERRUPT RULES AND PRIORITY MANAGEMENT

■ A Reset can interrupt the NMI and peripheral

interrupt routines

■ The Non Maskable Interrupt request has the

highest priority and can interrupt any peripheral interrupt routine at any time but cannot interrupt another NMI interrupt.

■ No peripheral interrupt can in terrupt another. If

more than one interrupt request is pending, these are processed by the processor core according to their priority level: vector #1 has the highest priority while vector #4 the lowest. The priority of each interrupt source is fixed by hardware (see Interrupt Mapping table).

6.2 INTERRUPTS AND LOW POWER MODES

All interrupts cause the processor to exit from WAIT mode. Only the external and som e specific interrupts from the on-chip peripherals cause the processor to exit from STOP mode (refer to the

“Exit from STOP“ column in the Interrupt Mapping Table).

6.3 NON MASKABLE INTERRUPT

This interrupt is t riggered when a fallin g edge occurs on the NMI pin regardless of the state of the GEN bit in the IOR register. An interrupt request on NMI vector #0 is latched by a flip flop which is automatically reset by the core at the beginning of the NMI service routine.

6.4 PERIPHERAL INTERRUPTS

Different peripheral interrupt flags in the peripheral control registers are able to cause an interrupt when they are active if both:

– The GEN bit of the IOR register is set – The corresponding enable bit is set in the periph-

eral control register.

Peripheral interrupts are linked to vectors #3 and #4. Interrupt requests are flagged by a bit in their corresponding control register. This means that a request cannot be lost, because the flag bit m ust be cleared by user software.

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6.5 EXTERNAL INTERRUPTS (I/O Ports)

External interrupt vectors can be loaded into the PC register if the corresponding external interrupt occurred and if the GEN bit is set. These interrupts allow the processor to exit from STOP mode.

The external interrupt polarity is selected t hrough the IOR register.

External interrupts are linked to vectors #1 and #

2. Interrupt requests on vector #1 can be configu red

either as edge or le vel-s ensitive us in g t he LES bit in the IOR Register.

Interrupt requests from vector #2 are always edge sensitive. The edge polarity can be configured using the ESB bit in the IOR Register.

In edge-sensitive mode, a latch is set when a edge occurs on the interrupt source li ne and is cleared when the associated interrupt routine is started. So, an interrupt request can be stored until completion of the currently executing interrupt routine, before being processed. If several interrupt requests occurs before comp let ion o f the cu rrent interrupt routine, only the first request is stored.

Storing of interrupt requests is not possible i n level sensitive mode. To be taken into account, the lo w level must be present on the interrupt pin when the MCU samples the line after instruction execution.

6.5.1 Notes on using External Interrupts ESB bit Spuri ous Interrupt on Ve c tor # 2

If a pin associated with interrupt vector #2 is configured as interrupt with pull-up, whenever vector #2 is configured to be rising edge sensitive (by setting th e ESB b it in the I OR register ), a n interrupt i s latched although a rising edge may not have occured on the associated pin.

This is due to the vector #2 circuitry.The workaround is to discard this first interrupt request in the routine (using a flag for example).

Masking of One Interrupt by Another on Vector #2.

When two or more port pins (associated with interrupt vector #2) are configured together as input with int errupt (falling edge sensitive ), as long as one pin is stuck at ’0’, the other pin can never generate an interrupt even if an act ive edge occurs at this pin. The same thin g occurs when one pin is stuck at ’1’ and interrupt vector #2 is configured as rising edge sensitive.

To avoid this the f irst pin must input a signal that goes back up to ’1’ right after the falling edge. Otherwise, in the interrupt rou tine for the first pin, de-

activate the “input with interrupt” mode using the port control registers (DDR, OR, DR). An active edge on another pin can then be latched.

I/O port Configuration Spurious Interrupt on

Vector #2

If a pin associated with interrupt vector #2 is in ‘input with pull-up’ st ate, a ‘0’ level is present on t he pin and the ESB bit = 0, when the I/O pin is configured as interrupt with pull-up by writing to the DDRx, ORx and DRx register bits, an interrupt is latched although a falling edge may not have occurred on the associated pin.

In the opposite case, if the pin is in interrupt with pull-up state , a 0 level is present on the pin and the ESB bit =1, when the I/O po rt is con figured as input with pull-up by writing to the DDRx, ORx and DRx bits, an interrupt is latched although a rising edge may not have occurred on the associated pin.

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6.6 INTERRUPT HANDLING PROCEDURE

The interrupt procedure is very similar to a call procedure, in fact the user ca n consider the interrupt as an asynchronous call procedure. As this is an asynchronous event, the user cannot know the context and the time at which it occurred. As a result, the user should save all Data space registers which may be used within the interrupt routines. The following list summarizes the interrupt procedure:

When an interrupt request occurs, the following actions are performed by the MCU automatically:

– The co re switches from the normal flags to the

interrupt flags (or the NMI flags).

– The PC contents are stored in the top level of the

stack.

– The normal interrupt lines are inhibited (NMI still

active). – The internal latch (if any) is cleared. – The associated interrupt vector is loaded in the PC.

When an interrupt request occurs, the following actions must be performed by the user software:

– User selected registers have to be saved within

the interrupt service routine (normally on a soft-

ware stack). – The so urce of the interrupt must be determined

by polling the interrupt flags (if more than one

source is associated with the same vector). – The RETI (RETurn from Interrupt) instruction

must end the interrupt service routine. After the RETI instruction is executed, the MCU re-

turns to the main routine. Caution: When a maskable interrupt occurs while

the ST6 core is in NORMAL mode and during the execution of an “ldi IOR, 00h” instruction (disabling all maskable interrupts): if the interrupt request occurs during the first 3 cycles of the “ldi” instruction (which is a 4-cycle instruction) the core will switch to int errupt mo de BUT the flags CN and Z N will NOT switch to the interrupt pair CI and ZI.

6.6.1 Interrupt Response Time

This is defined as the time between the mom ent when the Program Counter is loaded wi th the interrupt vector and when the program has jump to the interrupt subroutine and is ready to execute the code. It depends on when t he in terrupt occurs while the core is processing an instruction.

Figure 18. Interrupt Processing Flow Chart

Table 6. Interrupt Response Time

One CPU cycle is 13 exte rn al clock cycles thu s 1 1 CPU cycles = 11 x (13 /8M) = 17.875 µs with an 8 MHz external quartz.

Minimum 6 CPU cycles Maximum 11 CPU cycles

INSTRUCTION

FETCH

INSTRUCTION

EXECUTE

INSTRUCTION

WAS

THE INSTRUCTION

A RETI

ENABLE

MASKABLE INTERRUPTS

SELECT

NORMAL FLAGS

“POP”

THE STAC KED PC

IS THE R E AN

AN INTERRUPT REQUEST

AND INTERRUPT MASK?

SELECT

INTERRUPT FLAGS

PUSH T H E

PC INTO T H E STACK

LOAD PC FROM

INTERRUPT VECTOR

DISABLE

MASKABLE INTERRUPT

YES

IS THE CORE

ALREADY IN

NORMAL MODE?

YES

CLEAR

INTERNAL LATCH

If a latch is present on the interrupt source line

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6.7 REGISTER DESCRIPTION INTERRUPT OPTION REGISTER (IOR)

Address: 0C8h — Write Only Reset status: 00h

Caution: This register is write-only and cannot be accessed by single-bit operations (SET, RES, DEC,...).

Bit 7 =Reserved, must be cleared.

Bit 6 = LES

Level/Edge Selection bit

0: Falling edge sensitive mode is s elected for inter-

rupt vector #1

1: Low level sensitive mode is selected for inter-

rupt vector #1

Bit 5 = ESB

Edge Selection bit

. 0: Falling edge mode on interrupt vector #2 1: Rising edge mode on interrupt vector #2

Bit 4 = GEN

Global Enable Interrupt

. 0: Disable all maskable interrupts 1: Enable all maskable int e rru p ts

Note: When the GEN bit is cleared, the NMI interrupt is active but cannot be used to exit from STOP or WAIT modes.

Bits 3:0 = Reserved, must be cleared.

Table 7. Int errupt Mappin g

- LES ESB GEN - - - -

Vector

number

Source

Block

Description

Label

Flag

Exit

from

STOP

Vector

Address

Priority

Order

RESET Reset N/A N/A yes FFEh-FFFh

Vector #0 NMI Non Maskable Interrupt N/A N/A yes FFCh-FFDh

NOT USED

FFAh-FFBh

FF8h-FF9h Vector #1 Port A Ext. Interrupt Port A N/A N/A yes FF6h-FF7h Vector #2 Port B, C Ext. Interrupt Port B, C N/A N/A yes FF4h-FF5h Vector #3 TIMER Timer underflow TSCR TMZ yes FF2h-FF3h Vector #4 ADC End Of Conversion ADCR EOC no FF0h-FF1h

Priority

Lowest

Highest

Priority

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7 POWER SAVING MODES

7.1 INTRODUCTION

To give a large measure of flexibility to the application in terms of power consumption, two main power saving modes are implemented in the ST6 (see

Figure 19).

In addition, the Low Frequency Auxiliary Oscillator (LFAO) can be used inste ad of the main oscillator to reduce power consumption in RUN and WAIT modes.

After a RESET the normal operating mode is selected by default (RUN mode). This mode drives the device (CPU and embedded peripherals) by means of a master clock which is based on the main oscillator frequency.

From Run mode, the different power saving modes may be selected by calling the specific ST6 software instruction or for the LFAO by setting the relevant register bit. For more information on the LFAO, please refer to the Clock chapter.

Figure 19. Power Saving Mode Tran sitions

POWER CONSUMPTION

WAIT

LFAO

RUN

STOP

High

Low

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7.2 WAIT MODE

The MCU goes into WAIT mode as soon as the WAIT instruction is executed. This has the following effects:

– Program execution is stopped, the microcontrol-

ler software can be considered as being in a “frozen” state.

– RAM contents and peripheral registers are pre-

served as long as the power supply voltage is higher than the RAM retention voltage.

– The os cillator is kept running to provide a clock

to the peripherals; they are still active.

WAIT mode can be used when the use r wants to reduce the MCU power consumption during idle periods, wh ile n ot lo s ing trac k o f time or the ability to monitor external events. WAIT mode places the MCU in a low power consumption mode by stopping the CPU. The active oscillator (main oscillator or LFAO) is kept running in order to provide a clock signal to the peripherals.

If the power consumption has to be further reduced, the Low Frequency Auxiliary Oscillator (LFAO) can be used in place of the main oscillator, if its operating frequency is lower. If requ ired, the LFAO must be sw itched on befo re entering WA IT mode.

Exit from Wait mode

The MCU remains in WAIT mode until one of th e following events occurs:

– RESET (Watchdog, LVD or RESET

pin) – A periphe ral interrupt (timer, ADC,...), – An external interrupt (I/O port, NMI)

The Program Counter then branches to the starting address of the interrupt or RESET service routine. R e fer to Figure 20.

See also S ect ion 7.4.1.

Figure 20. WAIT Mode Flowchart

WAIT INSTRUCTION

RESET

INTERRUPT

Clock to CPU

OSCILLATOR Clock to PERIPHERALSOnYes

FETCH RESET VECTOR

OR SERVICE INTERRUPT

2048 OR 32768

Clock to CPU

OSCILLATOR Clock to PERIPHERALS

Restart

Yes Yes

DELAY

CLOCK CYCLE

OSCILLATOR Clock to PERIPHERALS

Clock to CPU Yes

Yes

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7.3 STOP MODE

STOP mode is the lowest power consumption mode of the MCU ( s ee Figure 22).

The MCU goes into STOP mode as soon as the STOP instruction is executed. This has the following effects:

– Program execution is stopped, the microcontrol-

ler can be considered as being “frozen”.

– The co ntents of RAM and the peripheral regis-

ters are kept safely as long as the power supply voltage is higher than the RAM retention voltage.

– The os cillator is stopped, so peripherals cannot

work except the those that can be driven by an extern al clock.

Exit fr o m STOP Mo de

The MCU remains in STOP mode until one of the following events occurs:

– RESET (Watchdog, LVD or RESET

pin) – A periphe ral interrupt (assuming this peripheral

can be driven by an external clock) – An external interrupt (I/O port, NMI) In all cases a delay of 2048 or 32 768 clock cy cles

INT

) is gene rated to ma ke sure the oscilla tor has

started properly.

The Program Counter then points to the starting address of the interrupt or RESET service routine (see Figure 21).

STOP Mode and Watchdog

When the Watchdog is ac tive (hardware or software activation), the STOP instruction is disabled and a WAIT instruction will be executed in its place unless the EXCTNL option bit is set to 1 in the option bytes and a a high level is present on the NMI pin. In this case, the STOP instruction will be executed and the Watchdog will be frozen.

Figure 21. STOP Mode Tim ing Over vie w

STOPRUN RUN

2048 or 32768

RESET

INTERRUPT

STOP

INSTRUCTION

FETCH

VECTOR

CYCLECLOCK

DELAY

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STOP MODE (Cont’d) Figure 22. STOP Mode Flowchart

Notes:

1. EXCTNL is an option bit. See option byte section for more details.

2. Peripheral clocked with an external clock source can still be active.

3. Only some specific interrupts can exit the MCU from STOP mode (such as external interrupt). Refer to the Interrupt Mapping table for more details.

STOP INSTRUCTION

RESET

INTERRUPT

FETCH RESET VECTOR

OR SERVICE INTERRUPT

WATCHDOG

ENABLE

DISABLE

EXCTNL

LEVEL

NMI PIN

RESET

INTERRUPT

VALUE

Clock to CPU

OSCILLATOR Clock to PERIPHERALS

Off No No

2048 or 32768

DELAY

Clock to CPU

OSCILLATOR Clock to PERIPHERALS

Restart

Yes Yes

Clock to CPU

OSCILLATOR Clock to PERIPHERALSOnYes

Yes

Clock to CPU

OSCILLATOR Clock to PERIPHERALSOnYes

CLOCK CYCLE

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7.4 NOTES RELATED TO WAIT AND STOP MODES

7.4.1 Ex it from W ai t and S t op Modes

7.4.1.1 NMI Interrupt

It should be noted that when the GEN bit in the IOR register is low (interrupts disabled), the NMI interrupt is active but cannot cause a wake up from STOP/WAIT modes.

7.4.1.2 Restart Sequence

When the MCU exits from WAIT or STOP mode, it should be noted that the restart sequence depends on the original state of the MCU (normal, interrupt or non-maskable interrupt mode) prior to entering WAIT or STOP mode, as well as on th e interrupt type.

Normal Mode. If the MCU was in the main routine when the WAIT or STO P instruction was executed, exit from Stop or Wait mode will occur as soon as an interrupt occurs; the related interrupt routine is executed and, on completion, the instruction which follows the STOP or WAIT instruction is then executed, providing no other interrupts are pending.

Non Maskable Interrupt Mode. If the STOP or WAIT instruction has been executed during execution of the non-maskable interrupt routine, the MCU exits from Stop or Wait mode as soon a s a n interrupt occurs: the instruction which follows the STOP or WAIT instruction is executed, and the MCU remains in non-maskable interrupt mode, even if another interrupt has been generated.

Normal Inte rrupt Mod e. If the MCU was in interrupt mode before the STOP or WAIT instruction was executed, it exits from STOP o r WAIT mode

as soon as an interrupt occurs. Nevertheless, t wo cases must be considered:

– If the interrupt is a normal one, the interrupt rou-

tine in which the WAIT or STOP mode was entered will b e c o mpleted, sta rti ng with the execution of the instruction which follows the STOP or the WAIT instruction, and the MCU is still in interrupt mode. At the end of this routine pending interrupts will be serviced according to their priority.

– In the event of a non-maskable interrupt, the

non-maskable interrupt service routine is processed first, then the routine in which the WAIT or STOP mode was entered will be completed by executing the instruction following the STOP or WAIT instruction. The MCU remains in normal interrupt mode.

7.4.2 Recommended MCU Configuration

For lowest power consumption during RUN or WAIT modes, the user software must configure the MCU as follows:

– Configure unused I/Os as output push-pull low

mode

– Place all peripherals in their power down modes

before entering STOP mode

– Select the Low Frequency Auxiliary Oscillator

(provided this runs at a lower frequency than the main osc illator).

The WAIT and STOP instructions are not executed if an enabled interrupt request is pending.

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8 I/O POR TS

8.1 INTRODUCTION

Each I/O port contains up to 8 p ins. Each pin can be programmed independently as digital input (with or without pull-up and interr upt generation), digital output (open drain, push-pull) or analog input (when available).

The I/O pins can be used in eithe r standard or alternate function mode.

Standard I/O mode is used for:

– Transfer of data through digital inputs and out-

puts (on specific pins):

– External interrupt generation

Alternate function mode is used for:

– Alternate signal input/output for the on-chip

peripherals

The generic I/O block diagram is shown in Figure

23.

8.2 FUNCTIONAL DESCRIPTION

Each port is associated wi th 3 reg isters located i n Data space:

– Data Register (DR) – Data Direction Register (DDR) – Option Register (OR) Each I/O pin may be programmed using the corre-

sponding register bits in the DDR, DR and OR registers: bit x corresponding to pin x of the port. Table

8 illustrates the various port configurations which

can be selected by user software. During MCU initialization, all I/O registers are

cleared and the input mode with pull-up and no interrupt generation is selected for all the pins, thus avoiding pin conflicts.

8.2.1 Digital Input Modes

The input configuration is sele cted by clearing the corresponding DDR register bit.

In this case, reading the DR register returns the digital value applied to the external I/O pin.

Different input modes can be selected by software through the DR and OR registers, see Table 8.

External Interrupt Function

All input lines can be individually connected by software to the interrupt system by programming the OR and DR registers accordingly. The interrupt trigger modes (fall ing edge, rising edge and low level) can be configured by software for each port as described in the Interrupt section.

8.2.2 Analog Inputs

Some pins can be configured as analog input s by programming the OR and DR registers accordingly, see Table 8. T hes e analo g inputs are connected to the on-chip 8-bit Analog to Digital Converter.

Caution: ONLY ONE

pin should be program med as an analog input at any time, since by select ing more than one input simultaneously their pins will be effectively shorted.

8.2.3 Output Modes

The output configuration is selecte d by setting the corresponding DDR register bit. In this case, writing to the DR register applies this digital value to the I/O pin through the latch. Then, reading the DR register returns the previously stored value.

Two different output modes can be selected by software through the OR register: push-pull and open-drain.

DR register value and output pin status:

Note: The open drain setting is not a true open drain. This means it has the same structure as the push-pull setting but the P-buffer is deactivated. To avoid damaging the device, please respect the V

OUT

absolute maximum rating described in the

Electrical Characteristics section.

8.2.4 Alternate Functions

When an on-chip peripheral is configured to use a pin, the alternate function (timer input/output.. .) is not systematically selected but has to be configured through the DDR, OR and DR registers. Refer to the chapter describing the peripheral for more details.

DR Push-pull Open-drain

1VDDFloating

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I/O PO R T S (Cont’d) Figure 23. I/O Port Block Diagram

Table 8. I/O Port Configurations

Note: x = Don’t care

DDR OR DR Mode Option

0 0 0 Input With pull-up, no interrupt 0 0 1 Input No pull-up, no interrupt 0 1 0 Input With pull-up and with interrupt 0 1 1 Input Analog input (when available) 1 0 x Output Open-drain output (20mA sink when available) 1 1 x Output Push-pull output (20mA sink when available)

RESET

ST6

INTERNAL

DATA

DIRECTION

OPTION

TO INTERRUPT

TO ADC

N-BUFFER

P-BUFFER

PULL-UP

CMOS SCHMITT TRIGGER

Pxx I/O Pin

BUS

CLAMPING

DIODES

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I/O PO R T S (Cont’d)

8.2.5 Instructions NOT to be used to access Port Data registers (SET, RES, INC and DEC)

DO NOT USE READ-MODIFY-WRITE INSTRUCTIONS (SET, RES, INC and DEC) ON PORT DATA REGI STERS IF ANY P IN OF TH E PORT IS CONFIGURED IN INPUT MODE.

These instructions make an implicit read and write back of the entire register. In port input mode, however, the data register reads from the input pins directly, and not from the data register latches. Since data register information in input mode is used to set the characteristics of the input pin (interrupt, pull-up, analog input), these may be uni ntentionally reprogrammed depending on the state of the input pins.

As a general rule, it is better to only use single bit instructions on data registers when the whole (8bit) port is in output mode. In the case of inputs or of mixed inputs and outputs, it is advisable to keep a copy of the data regist er in RAM. Single bit instructions may then be used on the RAM copy, after which the whole copy register can be written to the port data register:

SET bit, datacopy LD a, datacopy LD DRA, a

8.2.6 Recommendations

1. Safe I/O State Switching Sequence

Switching the I/O ports from one state to another should be done in a se quence which ensures that no unwanted side effects can occur. The recommended safe transitions are illustrated in Figure 24 The Interrupt Pull-up to Input Analog transition (and vice-vesra) is potentially risky and should be avoided when changing the I/O operating mode.

2. Handling Unused Port Bits

On ports that have less than 8 external pins connected:

– Leave the unbonded pins in reset state and do

not change their configuration.

– Do not use instructions that act on a whole port

register (INC, DEC, or read operations). Unavailable bits must be masked by software (AND instruction). Thus, when a read operation performed on an incomplete port is followed by a comparison, use a mask.

3. High Impedance Input

On any CMOS de vice, it is not recommended to connect high impedance on input pins. The choice of these impedance has to be done with respect to the maximum leakage current de fined in the datasheet. The risk is to be close o r out o f specification on the input levels applied to the device.

8.3 LOW POWER MODES

The WAIT and STOP instructions allow the ST62xx to be used in situations where low power consumption is needed. The lowest power consumption is achieved by configuring I/Os in output push-pull low mode.

8.4 INTERRUPTS

The external interrupt event generates an interrupt if the corresponding configuration is selected with DDR, DR and OR registers (see Table 8) and the GEN-bit in the IOR register is set.

Figure 24. Diagram showing Safe I/O State Transitions

Note *. xxx = DDR, OR, DR Bits respectively

Mode Description

WAIT

No effect on I/O ports. External interrupts cause the device to exit from WAIT mode.

STOP

No effect on I/O ports. External interrupts cause the device to exit from STOP mode.

Interrupt pull-up

Output Open Drain

Output Push-pull

Input pull-up (Reset state)

Input

Analog

Output

Open Drain

Output

Push-pul l

Input

010*

000

100

110

011

001

101

111

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I/O PO R T S (Cont’d) Table 9. I/O Port Option Selections

Note 1. Provided the correct configuration has been selected (see Table 8).

MODE

AVAILABLE

(1)

SCHEMATIC

Digital Input

Input

PA0-PA7 PB0-PB7 PC4-PC7

DDRx0ORx0DRx

Reset state

Input

with pull up

PA0-PA7 PB0-PB7 PC4-PC7

DDRx0ORx0DRx

Input

with pull up

with interrupt

PA0-PA7 PB0-PB7 PC4-PC7

DDRx0ORx1DRx

Analog Input

PA4-PA7 PB0-PB7 PC4-PC7

DDRx0ORx1DRx

Digital output

Open drain output (5mA)

Open drain output (20 mA)

PA4-PA7 PB0-PB7 PC4-PC7

PA0-PA3

DDRx1ORx0DRx

0/1

Push-pull output (5mA)

Push-pull output (20 mA)

PA4-PA7 PB0-PB7 PC4-PC7

PA0-PA3

DDRx1ORx1DRx

0/1

Data in

Interrupt

Data in

Interrupt

Data in

Interrupt

ADC

Data out

P-buffer disconnected

Data out

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I/O PO R T S (Cont’d)

8.5 REGISTER DESCRIPTION DATA REGISTER (DR)

Port x Data Register DRx with x = A, B or C. Addresses 0C0h, 0C1h and 0C2h- Read/Write

Reset Value: 0000 0000 (00h)

Bits 7:0 = DR[7:0]

Data register bits.

Reading the DR register returns either the DR register latch content (pin configured as output) or the digital value applied to the I/O pin (pin conf igured as input).

Caution: In input mode, modifying this register will modify the I/O port configuration (see Table 8).

Do not use the Single bit instructions on I /O port data registers. See (Section 8.2.5).

DATA DIRECTION REGISTER (DDR)

Port x Data Direction Register DDRx with x = A, B or C. Addresses: 0C4h, 0C5h and 0C6h - Read/Write

Reset Value: 0000 0000 (00h)

Bits 7:0 = DDR[7:0]

Data direction register bits.

The DDR register gives the input /output direction configuration of the pins. Each bit is set and cleared by software. 0: Input mode 1: Output mode

OPTION REGISTER (OR)

Port x Option Register ORx with x = A, B or C. Addresses: 0CCh, 0CDh and 0CEh - Read/ Write

Reset Value: 0000 0000 (00h)

Bits 7:0 = OR[7:0]

Option register bits.

The OR register allows to distinguish in output mode if the push-pull or open drain configuration is selected.

Output mode: 0: Open drain output(with P-Buffer deactivated) 1: Push-pull Output

Input mode: See Table 8. Each bit is set and cleared by software. Caution: Modifying this register, will a lso modify

the I/O port configuration in inp ut mode. (see Ta-

ble 8).

Table 10. I/O Port Register Map and Reset Values

DR7 DR6 DR5 DR4 DR3 DR2 DR1 DR0

DDR7 DDR6 DDR5 DDR4 DDR3 DDR2 DDR1 DDR0

OR7 OR6 OR5 OR4 OR3 OR2 OR1 OR0

Address

(Hex.)

Label

76543210

Reset Value

of all I/O port registers

00000000

0C0h DRA

MSB LSB0C1h DRB 0C2h DRC 0C4h DDRA

MSB LSB0C5h DDRB 0C6h DDRC

0CCh ORA

MSB LSB0CDh ORB

0CEh ORC

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9 ON-CHIP PERIPHERALS

9.1 WATCHDOG TIMER (WDG)

9.1.1 Introd uction

The Watchdog tim er is used to detect t he occurrence of a software fault, usually generated by external interference or by unforeseen logi cal conditions, which causes the application program to abandon its normal seque nce. The W atchdog circuit generates an MCU reset o n expiry of a programmed time period, unless the program refresh-

es the counter’s contents before the SR bit becomes cleared.

9.1.2 Main Features

■ Programmable timer (64 steps of 3072 clock

cycles)

■ Software reset

■ Reset (if watchdog activated) when the SR bit

reaches zero

■ Hardware or software watchdog activation

selectable by option bit (Refer to the option bytes section)

Figure 25. Watchdog Bl ock Diagram

RESET

7-BIT DOWNCOUNTER

int /12

CLOCK DIVIDER

WATCHDOG REGISTER (WDGR)

256

bit 0

bit 7

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WATCHD OG TI M E R (Cont’d)

9.1.3 Functional Description

The watchdog activation is selected through an option in the option bytes:

– HARDWARE Watchdog option After reset, the watchdog is permanently active,

the C bit in the WDGR is forced high and the us er can not change it. However, this bit can be read equally as 0 or 1.

– SOFTWARE Watchdog option After reset, the watchdog is deactivated. The func-

tion is activated by setting C bit in the WDGR register. Once activated, it cannot be deactivated. The counter value stored in the WDGR register (bits SR:T0), is decremented every 3072 clock cycles. The length of the timeout period can be programmed by the user in 64 steps of 3072 clock cycles.

If the watchdog is activated (by se tting the C bit) and when the SR bit is cleared, the watchdog initiates a reset cycle pulling the reset pin low for typically 500ns.

The application program must write in the WDG R register at regular intervals during normal operation to prevent an MCU reset. The value to be stored in the WDGR register must be between FEh and 02h (see Table 11). To run the watchdog function the following conditions must be true:

– The C bit is set (watchdog activated) – The SR bit is set to prevent generating an imme-

diate reset

– The T[ 5:0] bits contain the numb er of decre-

ments which represent the time delay before the watchdog produces a reset.

Table 11. Watchdog Timing (f

OSC

= 8 MHz)

9.1.3.1 Software Reset

The SR bit can be used to generate a software reset by clearing the SR bit while the C bit is set.

9.1.4 Recommendations

1. The Watchdog plays an important supporting role in the high noise immunity of ST62xx devices, and should be used wherever possible. Watchdog related options should be s elected on the basis of a trade-off between application security and STOP

mode availability (refer to the description of the WDACT and EXTCNTL bits on the Option Bytes).

When STOP m ode is not required, hardware activation without EXTERNAL STOP MODE CONTROL should be preferred, as it provides maximum security, especially during power-on.

When STOP mode i s required, hardware activation and EXTERNAL STOP MODE CONTROL should be chosen. NM I shoul d be high by default, to allow STOP mode to be entered when the MCU is idle.

The NMI pin can be connected to an I/O line (see

Figure 26) to allow its state to be controlled by soft-

ware. The I/O line can then be used to keep NMI low while Watchdog protection is required, or to avoid noise or key bounce. When no more processing is required, the I/O line is released and the device placed in STOP mode for lowest power consumption.

Figure 26. A typical circuit maki ng use of the EXERNAL STOP MODE CONTROL feature

2. When software activation is selected (WDACT bit in Option byte) and the Watchdog is not activated, the downcounter may be used as a simple 7bit timer (remember that the bits are in reverse order).

The software activation opt ion should be chosen only when the Watchdog counter is to be used as a timer. To ensure the Watchdog has not been unexpectedly activated, the following instructions should be executed:

jrr 0, WDGR, #+3 ; If C=0,jump to next ldi WDGR, 0FDH ; SR=0 -> reset

WDGR Register

initial value

WDG timeout period

(ms)

Max. FEh 24.576

Min. 02h 0.384

NMI

SWITCH

I/O

VR02002

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WATCHD OG TI M E R (Cont’d) These instructions test the C bit and reset the

MCU (i.e. disable the Watchdog) i f the bit is set (i.e. if the Watchdog is active), thus disabling the Watchdog.

For more information on the use of the watchdog, please read application note AN1015.

Note: This note applies only when the watchdog is used as a standard timer. It is recommended to read the counter twice, as it may sometimes return an invalid value if the read is perfo rmed while the counter is decremented (counter bits in transient state). To validate the return value, both values read must be equal. The counter decrements every 384 µs at 8 MHz f

OSC

9.1.5 Low Power Modes

9.1.6 Interrupts

None.

Mode Description

WAIT No effect on Watchdog. STOP

Behaviour depends on the EXTCNTL option in the Option bytes:

1. Watchdog disabled:

The MCU will enter Stop mode if a STOP instruction is executed.

2. Watchdog enabled and EXTCNTL option disabled:

If a STOP instruction is encountered, it is interpreted as a WAIT.

3. Watchdog and EXTCNTL option enabled:

If a STOP instruction is encountered when the NMI pin is low, it is interpreted as a WAIT. If, however, the STOP instruction is encountered when the NMI pin is high, the Watchdog counter is frozen and the CPU enters STOP mode. When the MCU exits STOP mode (i.e. when an interrupt is generated), the Watchdog resumes its activity.

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WATCHD OG TI M E R (Cont’d)

9.1.7 Register Description WATCHDOG REGISTER (WDGR)

Address: 0D8h - Read /Wri te Reset Value: 1111 1110 (FEh)

Bits 7:2 = T[5:0]

Downcounter bits

Caution: These bits are reversed and shifted with respect to the physical counter: bit-7 (T0) is the LSB of the Watchdog downcounter and bit-2 (T5) is the MSB.

Bit 1 = SR:

Software Reset bit

Software can generate a reset by clearing this bit while the C bit is set. Whe n C = 0 (Watchdog deactivated) the SR bit is the MSB of the 7-bit timer. 0: Generate (write)

1: No software reset generated, MSB of 7-bit timer

Bit 0 = C

Watchdog Control bit

. If the hardware option is selected (WDACT bit in Option byte), this bit is forced hi gh and ca nnot be changed by the user (the Watchdog is always active). When the software option is selected (WDACT bit in Option byte), the Watchdog function is activated by setting the C bit, and cannot then be deactivated (except by resetting the MCU).

When C is kept cleared the counter can be used as a 7-bit timer. 0: Watchdog deactivated 1: Watchdog activated

T0 T1 T2 T3 T4 T5 SR C

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9.2 8-BIT TIMER

9.2.1 Introd uction

The 8-Bit Timer on-chip peripheral is a free running downcounter based on an 8-bit downcounter with a 7-bit programmable prescaler, giving a maximum count of 2

. The peripheral may be config-

ured in three different operating modes.

9.2.2 Main Features

■ Time-out downcounting mod e with up t o 15-bit

accuracy

■ External counter clock source (valid also in

STOP mode)

■ Interrupt capability on counter underflow

■ Output signal generation

■ External pulse length measurement

■ Event counter

The timer can be used in WAIT and S TOP m odes to wake up the MCU.

Figure 27. Timer Block Diagram

INTERRUPT

TMZ

ETI TOUT DOUT PSI PS2 PS1 PS0

TSCR

PROGRAMMABLE PRESCALER

PSCR6

PSCR5 PSCR4 PSCR3 PSCR2 PSCR1 PSCR0

PSCR REGISTER 0

TCR7

TCR6 TCR5 TCR4 TCR3 TCR2 TCR1 TCR0

TCR

RELOAD

8-BIT DOWN COUNTE R

TIMER

PRESCALER

COUNTER

EXT

INT/12

LATCH

PSCR7

/4/8/16/32/64/128

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8-BI T TIMER (Cont’d)

9.2.3 Counter/Prescaler Description Prescaler

The prescaler input can be the internal frequency f

INT

divided by 12 or an external clock applied to the TIMER pin. The prescaler d ecrements on the rising edge, depending on the division factor programmed by the PS[2:0] bits in the TSCR register.

The state of the 7-bit prescaler can be read in the PSCR register.

When the prescaler reaches 0, it is automa tically reloaded with 7Fh.

Counter

The free running 8-bit downcounter is fed by the output of the programmable prescaler, and is decremented on every rising edge of the f

COUNTER

clock signal coming from the prescaler. It is possible to read or write the content s of the

counter on the fly, by reading or writing the timer counter register (TCR).

When the downcounter reach es 0, it is automatically reloaded with the value 0FFh.

Counter Clock and Prescaler

The counter clock frequency is given by:

COUNTER

= f

PRESCALER

/ 2

PS[2:0]

where f

PRESCALER

can be:

–f

INT

/12

–f

EXT

(input on TIMER pin)

–f

INT

/12 gated by TIMER pin

The timer input clock feeds the 7-bit programmable prescaler. The prescaler output can be programmed by selecting one of the 8 available prescaler taps using the PS[2:0] bits i n t he St atus/Control Register (TSCR). Thus the division factor of the prescaler can be set to 2

(where n equals 0, to

7). See Figure 27. The clock input is enabled by the PSI (Prescaler

Initialize) bit in the TSCR register. When PSI is reset, the counter is frozen and the prescaler is loaded with the value 7Fh. When PSI is set, the pres-

caler and the counter run at the rat e of the s el ected clock source.

Counter and Prescaler Initialization

After RESET, the counter and the prescaler are initialized to 0FFh and 7Fh respectively.

The 7-bit prescaler can be initialized to 7Fh by clearing the PSI bit. Direct write access to the prescaler is also possible when PSI =1. Then, any value between 0 and 7Fh can be loaded into it.

The 8-bit counter can be initialized separately by writing to the TCR register.

9.2.3.1 8-bit Counting and Interrup t Capability on Counter Underflow

Whatever the division factor defined for the prescaler, the Timer Counter works as an 8-bit downcounter. The input clock frequency is user selectable using the PS[2:0] bits.

When the downcounter decrements to zero, the TMZ (Timer Zero) bit in the TSCR is set. If the ETI (Enable Timer Interrupt) bit in the TSCR is also set, an interrupt request is generated.

The Timer interrupt can be used to exit the MCU from WAIT or STOP mode.

The TCR can be written at any time by software to define a time period ending with an underflow event, and therefore manage delay or t imer functions.

TMZ is set when the dow ncounter reaches zero; however, it may also be set by writing 00h in the TCR register or by setting bit 7 of the TSCR register.

The TMZ bit must be cleared by user software when servicing the timer interrupt to avoid undesired interrupts when leaving the interrupt service routine.

Note: A write to the TCR register will predominate over the 8-bit counter decrement to 00h function, i.e. if a write and a TCR register decrement to 00h occur simultaneously, the write will take precedence, and the TMZ bit is not set until the 8-bit counter underflows again.

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8-BI T TIMER (Cont’d)

9.2.4 Functional Description

There are three operating modes, which are selected by the TOUT and DOUT bits (see TSCR register). These three modes correspond to the two clocks which can be connected to the 7-bit prescaler (f

INT

÷ 12 or TIM ER pin signal), and to

the output mode. The settings for the different operating modes are

summarized Table 12.

Table 12. Timer Operating Modes

9.2.4.1 Gated Mode

(TOUT = “0”, DOUT = “1”) In this mode, the prescaler i s dec rem ented by the

Timer clock input, but only when the signa l on th e TIMER pin is held h igh (f

INT

/12 gated by T IMER

pin). See Figure 28 and Figure 29. This mode is selected by clearing the TOUT bit in

the TSCR register (i.e. as input) and setting the DOUT bit.

Note: In this mode, if the TIMER pin is multiplexed, the corresponding port control bits have to be set in input wi th pull-up configuration through

the DDR, OR and DR registers. For more details, please refer to the I/O Ports section.

Figure 28. f

TIMER

Clock in Gate d Mode

Figure 29. Ga te d M ode Operation

TOUT DOUT

Timer

Function

Application

Event Counter

(input)

External counter clock

source

Gated input

(input)

External Pulse length

measurement

Output “0”

(output) Output signal

Output “1”

(output)

generation

PRESCALER

TIMER

INT

/12

EXT

xx1

COUNTER VALUE

TIMER PIN

TIMER CLOCK

VALU E 1

VALUE 2

PULSE LENGTH

xx2

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8-BI T TIMER (Cont’d)

9.2.4.2 Event Counter Mode

(TOUT = “0”, DOUT = “0”) In this mode, the TIM ER pin is the input clock of

the Timer prescaler which is decremented on every rising edge of the input clock (allowing event count). See Figure 30 and Figure 31.

This mode is selected by clearing the TOUT bit in the TSCR register (i.e. as input) and clearing the DOUT bit.

Note: In this mode, if the TIMER pin is multiplexed, the corresponding port control bits have to be set in input with pull-up configuration.

Figure 30. f

TIMER

Clock in Event Counter Mode

Figure 31. Event Counter Mode Operation

9.2.4.3 Output Mode

(TOUT = “1”, DOUT = “data out”) In Output mode, the TIMER pin is connected to the

DOUT latch, hence the Timer prescaler is clocked by the prescaler clock input (f

INT

/12). See Figure 32.

The user can select the prescaler division ratio using the PS[2:0] bits in the TSCR register. When TCR decrements to zero, it sets the TMZ bit i n the TSCR. The TMZ bit can be tested under program control to perform a timer function whenever it goes high and has to be cleared by the user. The low-to-high TMZ

bit transition is used to latch the DOUT bit in the TSCR and, if the TOUT bit is set, DOUT is transferred to the TIMER pin. This operating mode allows external signal generation on the TIMER pin. See

Figure 33.

This mode is selected by s etting the TOUT bit in the TSCR register (i.e. as output) and s etting the DOUT bit to output a high level or clearing the DOUT bit to output a low level.

Note: As soon as t he TOUT bit is set, The timer pin is configured as output push-pull regardless of the corresponding I/O port control registers setting (if the TIMER pin is multiplexed).

Figure 32. Output Mode Control

Figure 33. Output Mode Operation

PRESCALERTIMER

XX1

COUNTER VALUE

TIMER PIN

VALU E 1

VALUE 2

XX2

TMZ

TIMER

TOUT

DOUT

LATCH

FFh

Counter

TIMER PIN

1st downcount:

Default output value is 0

At each zero event DOUT has to be copied to the TIMER

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8-BI T TIMER (Cont’d)

9.2.5 Low Power Mod es 9.2.6 Interrupts

Mode Description

WAIT

No effect on timer. Timer interrupt events cause the device to exit from WAIT mode.

STOP

Timer registers are frozen except in Event Counter mode (with external clock on TIMER pin).

Interrupt Event

Event

Flag

Enable

Bit

Exit from Wait

Exit from Stop

Timer Zero Event

TMZ ETI Yes Yes

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8-BI T TIMER (Cont’d)

9.2.7 Register Description PRESCALER COUNTER REGISTER (PSCR)

Address: 0D2h - Read/Write Reset Value: 0111 1111 (7Fh)

Bit 7 = PS CR7: Not used, always read as “0”. Bits 6:0 = PSCR[6:0]

Prescaler LSB.

TIMER COUNTER REGISTER (TCR)

Address: 0D3h - Read / Write Reset Value: 1111 1111 (FFh)

Bits 7:0 = TCR[7:0]

Timer counter bits.

TIMER STATUS CONTROL REGISTER (TSCR)

Address: 0D4h - Read/Write Reset Value: 0000 0000 (00h)

Bit 7 = TMZ

Timer Zero bit .

A low-to-high transition indicates that the timer count register has underflowed. It means that th e TCR value has changed from 00h to FFh. This bit must be cleared by user software. 0: Counter has not underflowed 1: Counter underflow occurred

Bit 6 = ETI

Enable Timer Interrupt.

When set, enables the timer interrupt request. If

ETI=0 the timer interrupt i s di sa bled. If ET I=1 and TMZ=1 an interrupt request is generated. 0: Interrupt disabled (reset state) 1: Interrupt enabled

Bit 5 = TOUT Timer Output Control

When low, this bit sel ects the input mode for the TIMER pin. When high the ou tput mode i s selected. 0: Input mode (reset state) 1: Output mode, t he TIMER pin is configured as push-pull output

Bit 4 = DOUT

Data Output.

Data sent to the timer output when TMZ is set high (output mode only). Input mode selection (input mode only).

Bit 3 = PSI:

Presca ler Ini tialize bit.

Used to initialize the prescaler and inhibit its counting. When PSI=“0” t he presc aler is set to 7Fh and the counter is inhibited. When PSI=“1” the prescaler is enabled to count downwards. As long as PSE=“1” both counter and prescaler are not running 0: Counting disabled 1: Counting enabled

Bits 1:0 = PS[2:0]

Prescaler Mux. Select.

These bits select the division ratio of the prescaler register.

Table 13. Prescaler Division Factors

Table 14. 8-Bit Timer Register Map and Reset Values

PSCR7PSCR6PSCR5PSCR4PSCR3PSCR2PSCR1PSCR

TCR7 TCR6 TCR5 TC R4 TC R3 TC R2 TCR1 TCR 0

TMZ ETI TOUT DOUT PSI PS2 PS1 PS0

PS2 PS1 PS0 Divided by

0 0 0 1 0 0 1 2 0 1 0 4 0118 10016 10132 11064 111128

Address

(Hex.)

0D2h

PSCR

Reset Value

PSCR70PSCR61PSCR51PSCR41PSCR31PSCR21PSCR11PSCR0

0D3h

TCR

Reset Value

TCR71TCR61TCR51TCR41TCR31TCR21TCR11TCR0

0D4h

TSCR

Reset Value

TMZ

ETI

TOUT0DOUT

PSI

PS2

PS1

PS0

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9.3 A/D CONVERTER (ADC)

9.3.1 Introd uction

The on-chip Analog to Digital Converter ( ADC) peripheral is a 8-bit, successive approximation converter. This peripheral has multiplexed analog input channels (refer to device pin out description) that allow the peripheral to convert the analog voltage levels from different sources.

The result of the conversion is stored in a 8-bit Data Register. The A/D converter is controlled through a Control Register.

9.3.2 Main Features

■ 8-bit conversion

■ Multiplexed analog input channels

■ Linear successive approximation

■ Data register (DR) which contains the results

■ End of Conversion flag

■ On/Off bit (to reduce consumption)

■ Typical conversion time 70 µs (with an 8 MHz

crystal)

The block diagram is shown in Figure 34.

Figure 34. ADC Block Diagram

OSC

EAI EOC STA PDS

ADCR

AIN0

AIN1

ANALOG TO DIGITAL

CONVERTER

AINx

PORT

MUX

ADR2

ADR1ADR3ADR7 ADR6ADR5 ADR4 ADR0

ADR

DIV 12

ADC

INT

DDRx

ORx DRx

I/O PORT

OFF

CR3

CR1

CR0

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A/D CONVERTER (Cont’d)

9.3.3 Functional Description

9.3.3.1 Analog Power Supply

The high and low level reference voltage pi ns are internally connected to the V

and VSS pins.

Conversion accuracy may therefore be impacted by voltage drops and noise in the event of heavily loaded or badly decoupled power supply lines.

9.3.3.2 Digital A/D Conversion Result

The conversion is monotonic, meaning that the result never decreases if t he analog i nput does not and never increases if the analog input does not.

If the input voltage (V

AIN

) is greater than or equal

to V

DDA

(high-level voltage reference) then the conversion result in the DR register is FFh (full scale) without overflow indication.

If input voltage (V

AIN

) is lower than or equal to

SSA

(low-level voltage reference) then the con-

version result in the DR register is 00h. The A/D converter is linear and the digital result of

the conversion is stored in the ADR regi ster. The accuracy of the conversion is described in the parametric section.

AIN

is the maximum recommended impedance for an analog input signal. If the impedance is too high, this will result in a loss of accuracy due to leakage and sampling not being completed in the allocated time. Refer to the electrical characteristics chapter for more details.

With an oscillator clock frequency less than

1.2MHz, conversion accuracy is decreased.

9.3.3.3 Analog Input Selection

Selection of the input pi n is done by configuring the related I/O line as an analog input via the Data Direction, Option and Data registe rs (refer to I/O ports description for additional information).

Caution: Only one I/O line m ust be c onf igured as an analog input at any time. T he us er must av oid any situation in which more than one I/O pin is selected as an analog input simultaneously, because they will be shorted internally.

9.3.3.4 Software Procedure

Refer to the Control register (ADCR) and Data register (ADR) in Section 9.3.7 for the bit definitions.

Analog Input Configuration

The analog inpu t must be con figured through t he Port Control registers (DDRx, ORx and DRx). Refer to the I/O port chapter.

ADC Configuration

In the ADCR register: – Reset the PDS bit to power on the ADC. This bit

must be set at least one instruction before the beginning of the conversion to allow stabilisation of the A/D converter.

– Set the EAI bit to enable the ADC interrupt if

needed.

ADC Conversion

In the ADCR register: – Set the STA bit to start a conversion. This auto-

matically clears (resets to “0”) the End Of Con-

version Bit (EOC). When a conversion is complete – The EOC bit is set by hardware to flag that con-

version is complete and that the data in the ADC

data conversion register is valid. – An interrupt is generated if the EAI bit was set Setting the STA bit will start a new count and will

clear the EOC bit (thus clearing the interrupt condition)

Note:

Setting the STA bit must be done by a different instruction from the instruction that powers-on the ADC (setting the PDS bit) in order to m ake sure the voltage to be converted is present on the pin.

Each conversion has to be separately initiated by writing to the STA bit.

The STA bit is continuously scanned so that, if the user sets it to “1” while a previous conversion is in progress, a new conversion is started before completing the previous one. The start bit (STA) is a write only bit, any attempt to read it will show a logical “0”.

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A/D CONVERTER (Cont’d)

9.3.4 Recommendations

The following six notes provide additional information on using the A/D converter.

1.The A/D converter does not feature a sample and hold circuit. The an alog voltage to be m easured should therefore be stable during the entire conversion cycle. Voltage variation should not exceed ±1/2 LSB for optimum conversion accuracy. A low pass filter may be used at the analog input pins to reduce input voltage variation during conversion.

2. When selected as an analog channel, the i nput pin is internally connected to a capacitor C

of typically 9p F. For maximum accu racy, this capacitor must be fully cha rged at the beginning of conversion. In the worst case, conversion starts one instruction (6.5 µs) after the channel has been selected. The impedance of the analog voltage source (ASI) in worst case conditions, is calculated using the following formula:

6.5µs = 9 x C

x ASI (capacitor charged to over 99.9%), i.e. 30 kΩ including a 50% guardband. The ASI can be higher if C

has been charged for a longer period by adding instructions before the start of conversion (adding more than 26 CP U cy cles is pointless).

3. Since the ADC is on the same chip as t he microprocessor, the user should not switch heavily loaded output signals during conversion, if high precision is required. Such switching will affect the supply voltages used as analog references.

4. Conversion accuracy depends on the quality of the power supplies (V

and VSS). The user must take special care to ensure a well regulated reference voltage is present on t he V

and VSS pins

(power supply voltage variations must be less than

0.1V/ms). This implies, in particular, that a suitable decoupling capacitor is used at the V

pin.

The converter resolution is given by:

The Input voltage (Ain) which is to be converted must be constant for 1µs before conversion and remain constant during conversion.

5. Conversion resolution can be improved if the power supply voltage (V

) to the mi crocontroller

is lowered.

6. In order to optimize the conversion resolution, the user can configure the microcontroller in WAIT mode, because this mode minimises noise dist ur-

bances and power supply variation s due to ou tput switching. Nevertheless, the WAIT instruction should be execut ed as s oon as possible after the beginning of the conversion, because execution of the WAIT instruction may cause a small variation of the V

voltage. The negative effect of this variation is minimized at the b eginning of the conversion when the converter is less sensitive, rather than at the end of conversion, when the leas t significant bits are determined. The best configuration, from an accuracy standpoint, is WAIT mode with the Timer stopped. In this case only the ADC peripheral and the oscillator are then still working. The MCU must be woken up from WAIT mode by the ADC interrupt at the end of the conversion. The microcontroller can also be woken up by the Timer interrupt, but this means the Timer must be running an d the resulting noise could affect conversion accuracy.

Caution: When an I/O pin is used as an analog input, A/D conversion accuracy will be impaired if negative current injections (V

INJ

< VSS) occur from adjacent I/O pi ns w ith analog input capability. Refer to Figure 35. To avoid this:

– Use another I/O port located further away from

the analog pin, preferably not multiplexed on the A/D converter

– Increase the input resistance R

IN J

(to reduce the

current injections) and reduce R

ADC

(to preserve

conversion accuracy).

Figure 35. Leakage from Digital Inputs

DDVSS

–

256

------------------------------- -

PBy/AINy

PBx/AINx

ADC

Leakage Current if V

INJ

< V

A/D

I/O Port (Digital I/O)

INJ

Converter

Digital Input

Analog Input

AIN

INJ

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A/D CONVERTER (Cont’d)

9.3.5 Low Power Modes

Note: The A/D converter may be disabled by clear-

ing the PDS bit. This feature allows reduced power consumption when no conversion is needed.

9.3.6 Interrupts

Note: The EOC bit is cleared only when a new

conversion is started (it cannot be cleared by writing 0). To avoid generating further EOC interrupt, the EAI bit has to be cleared within the ADC interrupt subroutine.

9.3.7 Register Description A/D CONVERTER CONTROL REGISTER (AD-

CR)

Address: 0D1h - Read/Write (Bit 6 Read Only, Bit 5 Write Only)

Reset value: 0100 0000 (40h)

Bit 7 = EAI

Enable A/D Interrupt.

0: ADC interrupt disabled 1: ADC interrupt enabled

Bit 6 = EOC

End of conversion. Read Only

When a conversion has been completed, this bit is set by hardware and an interrupt request is generated if the EAI bit is set. The EOC bit is automati-

cally cleared when the STA bit is set . Data in the data conversion register are valid only when this bit is set to “1”. 0: Conversion is not complete 1: Conversion can be read from the ADR register

Bit 5 = STA

: Start of Conversion. Write Only

. 0: No effect 1: Start conversion

Note: Setting this bit automatically clears the EOC bit. If the bit is set again when a conversion is in progress, the present conversion is stopped and a new one will take place. This bit is write only, any attempt to read it will show a logical zero.

Bit 4 = PDS

Power Down Selection.

0: A/D converter is switched off 1: A/D converter is switched on

Bit 3 = ADCR3 Reserved, must be cleared.

Bit 2 = OSCOFF

Main Oscillator off.

0: Main Oscillator enabled 1: Main Oscillator disabled

Note: This bit does not apply to the ADC peripheral but to th e main clock system. Refer to the Clock System section.

Bits 1:0 = ADCR[1:0] Reserved, must be cleared.

A/D CONVERTER DATA REGISTER (ADR)

Address: 0D0h - Read only Reset value: xxxx xxxx (xxh)

Bits 7:0 = ADR[7:0]

: 8 Bit A/D Conversion Result.

Table 15. ADC Register Map and Reset Values

Mode Description

WAIT

No effect on A/D Converter. ADC interrupts cause the device to exit from Wait mode.

STOP A/D Conv erter disabl ed.

Interrupt Event

Event

Flag

Enable

Bit

Exit

from

Wait

Exit from Stop

End of Conversion

EOC EAI Yes No

EAI EOC STA PDS

ADCR3OSC

OFF

ADCR1ADCR

ADR7 ADR6 ADR5 ADR4 ADR3 ADR2 ADR1 ADR0

Address

(Hex.)

Label

76543210

0D0h

ADR

Reset Value

ADR7

ADR6

ADR5

ADR4

ADR3

ADR2

ADR1

ADR0

0D1h

ADCR

Reset Value

EAI

EOC

STA

PDS

ADCR30OSCOFF0ADCR10ADCR0

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10 INSTRUCTIO N SET

10.1 ST6 ARCHITECTURE

The ST6 architecture has been designe d for max imum efficiency while keeping byte usage to a minimum; in short, to provide byte-efficient programming. The ST6 core has the abi lity to set or clear any register or RAM location bit in Data space using a single instruction. Furthermore, programs can branch to a selected address depending on the status of any bit in Data space.

10.2 ADDRESSING MODES

The ST6 has nine addressing mo des, which are described in the following paragraphs. Three different address spaces are available: Program space, Data space, and Stack space. Program space contains the instructions which are to be executed, plus the data for immedi ate mo de in structions. Data space contains the Accumulator, the X, Y, V and W registers, peripheral and Input/Output registers, the RAM lo cations and Data ROM loc ations (for storage of tables and constants). Stack space contains six 12-bi t RA M cells used t o st ack the return addresses for subroutines and interrupts.

Immediate. In immediate addressing mode, the operand of the instruction follows the opcode location. As the operand is a ROM byte, the immediate addressing mode is used to access constants which do not change during program execution (e.g., a constant used to initialize a loop counter).

Direct. In direct addressing mode , the address of the byte which is proc essed by the instruction is stored in the location which follows the opcode. Direct addressing allows the user to directly address the 256 bytes in Data Space memory with a single two-byte instruction.

Short Direct. The core can address the four RAM registers X, Y, V, W (locations 80h, 81h, 82h, 83h) in short-direct addressing mode. In this case, the instruction is only one byte and the selection of the location to be processed is contained in the opcode. Short direct addressing is a subset of direct addressing mode. (Note that 80h and 81h are also indirect registers).

Extended. In extended addressing mode, the 12bit address needed to define the instruction is obtained by concatenating the four least significant bits of the opcode with the byte following the opcode. The instructions (JP, CALL) which use ex-

tended addressing mode are able to branch to any address in the 4 Kbyte Program space.

Extended addressing mode instructions are two bytes long.

Program Counter Relative. Relative addressing mode is only us ed in conditional branch instructions. The instruction is used to perform a test and, if the condition is true, a branch with a span of -15 to +16 locations next to the address of the relative instruction. If the condition is not true, the instructio n w h ic h fo l lo ws t he rela t iv e i ns truct i o n is e x ec ut ed. Relative addressing mode instructions are one byte long. The opcode is obtained by adding the three most significant bits which characterize the test condition, one bit which determines whether it is a forward branch (when it is 0) or backward branch (when it is 1) and the four least significant bits which give the span of t he branch (0h t o Fh) which must be added or subtracted from the address of the relative instruction to obtain the branch destination address.

Bit Direct. In bit direct addressing mode, the bit to be set or cleared is pa rt of the opcode, and the byte following the opcod e poin ts to t he add ress of the byte in which the specified bit must be set or cleared. Thus, any bit in the 25 6 locat ions of Data space memory can be set or cleared.

Bit Test & Branch. Bit test and branch addressing mode is a combination of direct addressing and relative addressing. Bit test and branch instructions are three bytes long. The bit identification and the test c ondition are include d in the opcode byte. The address of the byte to be tested is given in the next byte. The third byte is the jump displacement, which is in the range of -127 to +128. This displacement can be determ ined using a label, which is converted by the assembler.

Indirect. In indirect addressing mode, the byte processed by the register-indirect instruction is at the address pointed to by the content of one of the indirect registers, X or Y (80h, 81h). The indirect register is selected by bit 4 of the opcode. Register indirect instructions are one byte long.

Inherent. I n inherent addres sing mo de, all the information necessary for executing t he instruction is contained in the opcode. These i nstructions are one byte long.

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10.3 INSTRUCTION SET

The ST6 offers a set of 40 basic instructions which, when combined with nine addressing modes, yield 244 usable opcodes. They can be divided into six different ty pes: load/store, arithmetic/logic, conditional branch, control instructions, jump/call, and bit manipu lat ion. T he f ollowing paragraphs describe the different types.

All the instructions belonging to a given type are presented in individual tables.

Load & Store. These instructions use one, two or three bytes depending on the addressing mode. For LOAD, one operand is the Accumulator and the other operand i s obtained from dat a memory using one of the addressing modes.

For Load Immediate, on e operand can be any of the 256 data space bytes while the other is always immediate data.

Table 16. Load & Store Instructions

Legend:

X, Y Index Registers, V, W Short Direct Registers # Immediate data (st ored in ROM memory) rr D at a space register

∆ Affected

* Not Affected

Instruction Addressing Mode Bytes Cycles

Flags

LD A, X Short Direct 1 4

∆

LD A, Y Short Direct 1 4

∆

LD A, V Short Direct 1 4

∆

LD A, W Short Direct 1 4

∆

LD X, A Short Direct 1 4

∆

LD Y, A Short Direct 1 4

∆

LD V, A Short Direct 1 4

∆

LD W, A Short Direct 1 4

∆

LD A, rr Direct 2 4

∆

LD rr, A Direct 2 4

∆

LD A, (X) Indirect 1 4

∆

LD A, (Y) Indirect 1 4

∆

LD (X), A Indirect 1 4

∆

LD (Y), A Indirect 1 4

∆

LDI A, #N Immediate 2 4

∆

LDI rr, #N Immediate 3 4 * *

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INSTRUCTION SET (Cont’d) Arithmetic and Logic. These instructions are

used to perform arithmetic calculations and logic operations. In AND, ADD, CP, SUB instructions one operand is always the accumulator while, depending on the addressing mode, the other can be

either a data spa ce memory location or an immediate value. In CLR, DEC, INC instructions the operand can be any of the 256 data space add resses. In COM, RLC, SLA the operan d is always the accumulator.

Table 17. Arithmetic & Logic Instructions

Notes:

X,Y Index Registers V, W S hort Direct Registers

∆ Affected

# Immediate data (stored in ROM memory) * Not Affected rr Da ta space register

Instruction Addressing Mode Bytes Cycles

Flags

ADD A, (X) Indirect 1 4

∆∆

ADD A, (Y) Indirect 1 4

∆∆

ADD A, rr Direct 2 4

∆∆

ADDI A, #N Immediate 2 4

∆∆

AND A, (X) Indirect 1 4

∆∆

AND A, (Y) Indirect 1 4

∆∆

AND A, rr Direct 2 4

∆∆

ANDI A, #N Immediate 2 4

∆∆

CLR A Short Direct 2 4

∆∆

CLR r Direct 3 4 * * COM A Inherent 1 4

∆∆

CP A, (X) Indirect 1 4

∆∆

CP A, (Y) Indirect 1 4

∆∆

CP A, rr Direct 2 4

∆∆

CPI A, #N Immediate 2 4

∆∆

DEC X Short Direct 1 4

∆

DEC Y Short Direct 1 4

∆

DEC V Short Direct 1 4

∆

DEC W Short Direct 1 4

∆

DEC A Direct 2 4

∆

DEC rr Direct 2 4

∆

DEC (X) Indirect 1 4

∆

DEC (Y) Indirect 1 4

∆

INC X Short Direct 1 4

∆

INC Y Short Direct 1 4

∆

INC V Short Direct 1 4

∆

INC W Short Direct 1 4

∆

INC A Direct 2 4

∆

INC rr Direct 2 4

∆

INC (X) Indirect 1 4

∆

INC (Y) Indirect 1 4

∆

RLC A Inherent 1 4

∆∆

SLA A Inherent 2 4

∆∆

SUB A, (X) Indirect 1 4

∆∆

SUB A, (Y) Indirect 1 4

∆∆

SUB A, rr Direct 2 4

∆∆

SUBI A, #N Immediate 2 4

∆∆

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INSTRUCTION SET (Cont’d) Conditional Branch. Branch instructions perform

a branch in the program wh en the s elected condition is met.

Bit Manipulation Instructions. These instructions can handle any bit in Data space memory. One group either sets or clears. The ot her group (see Conditional Branch) performs the bit test branch operations.

Control Instru ctions. Control instructions control microcontroller operations during program execution.

Jump and Call. These two instructions are used to perform long (12-bit) jumps or subroutine calls to any location in the whole program space.

Table 18. Conditional Branch Instructions

Notes:

b 3-bit address rr Data space register e 5 bit s igned displacement in the range -15 to +16

∆

Affected. The tested bit is shifted into carry.

ee 8 bit signed displacement in th e range -126 to +129 * Not Affected

Table 19. Bit Manipulation Instructions

Notes:

b 3-bit address * Not Affe ct ed rr Data space register Bit Manipul ation Instructions sho u l d not be used on Port Data Registers and any registers with rea d only and/or write only bits (see I/O port chapter)

Table 20. Control Instructio ns

Notes:

1. This instru ct i on i s deactivated and a WAIT is autom atically ex ecuted instead of a STOP if the watc hdog function is selected.

∆

Affected *Not Affected

Table 21. Jump & Call Instructions

Notes:

abc 12-bit address * N ot Affected

Instruction Branch If Bytes Cycles

Flags

JRC e C = 1 1 2 * * JRNC e C = 0 1 2 * * JRZ e Z = 1 1 2 * * JRNZ e Z = 0 1 2 * * JRR b, rr, ee Bit = 0 3 5 *

∆

JRS b, rr, ee Bit = 1 3 5 *

∆

Instruction Addressing Mode Bytes Cycles

Flags

SET b,rr Bit Direct 2 4 * * RES b,rr Bit Direct 2 4 * *

Instruction Addressing Mode Bytes Cycles

Flags

NOP Inherent 1 2 * * RET Inherent 1 2 * * RETI Inherent 1 2

∆∆

STOP

(1)

Inherent 1 2 * *

WAIT Inherent 1 2 * *

Instruction Addressing Mode Bytes Cycles

Flags

CALL abc Extended 2 4 * * JP abc Extended 2 4 * *

ST6215C/ST6225C

61/105

Opcode Map Summary. The following table contains an opcode map for the instructions used by the ST6

LOW

0000

0001

0010

0011

0100

0101

0110

0111

LOW

HI HI

0000

2 JRNZ 4 CALL 2 JRNC 5 JRR 2 JRZ 2 JRC 4 LD

0000

e abc e b0,rr,ee e NOP # e a,(x)

1pcr2ext1pcr3 bt1pcr 1prc1ind

0001

2 JRNZ 4 CALL 2 JRNC 5 JRS 2 JRZ 4 INC 2 JRC 4 LDI

0001

e abc e b0,rr,ee e x e a,nn

1pcr2ext1pcr3 bt1pcr1 sd1prc2imm

0010

2 JRNZ 4 CALL 2 JRNC 5 JRR 2 JRZ 2 JRC 4 CP

0010

e abc e b4,rr,ee e # e a,(x)

1pcr2ext1pcr3 bt1pcr 1prc1ind

0011

2 JRNZ 4 CALL 2 JRNC 5 JRS 2 JRZ 4 LD 2 JRC 4 CPI

0011

e abc e b4,rr,ee e a,x e a,nn

1pcr2ext1pcr3 bt1pcr1 sd1prc2imm

0100

2 JRNZ 4 CALL 2 JRNC 5 JRR 2 JRZ 2 JRC 4 ADD

0100

e abc e b2,rr,ee e # e a,(x)

1pcr2ext1pcr3 bt1pcr 1prc1ind

0101

2 JRNZ 4 CALL 2 JRNC 5 JRS 2 JRZ 4 INC 2 JRC 4 ADDI

0101

e abc e b2,rr,ee e y e a,nn

1pcr2ext1pcr3 bt1pcr1 sd1prc2imm

0110

2 JRNZ 4 CALL 2 JRNC 5 JRR 2 JRZ 2 JRC 4 INC

0110

e abc e b6,rr,ee e # e (x)

1pcr2ext1pcr3 bt1pcr 1prc1ind

0111

2 JRNZ 4 CALL 2 JRNC 5 JRS 2 JRZ 4 LD 2 JRC

0111

e abc e b6,rr,ee e a,y e #

1pcr2ext1pcr3 bt1pcr1 sd1prc

1000

2 JRNZ 4 CALL 2 JRNC 5 JRR 2 JRZ 2 JRC 4 LD

1000

e abc e b1,rr,ee e # e (x),a

1pcr2ext1pcr3 bt1pcr 1prc1ind

1001

2 JRNZ 4 CALL 2 JRNC 5 JRS 2 JRZ 4 INC 2 JRC

1001

e abc e b1,rr,ee e v e #

1pcr2ext1pcr3 bt1pcr1 sd1prc

1010

2 JRNZ 4 CALL 2 JRNC 5 JRR 2 JRZ 2 JRC 4 AND

1010

e abc e b5,rr,ee e # e a,(x)

1pcr2ext1pcr3 bt1pcr 1prc1ind

1011

2 JRNZ 4 CALL 2 JRNC 5 JRS 2 JRZ 4 LD 2 JRC 4 ANDI

1011

e abc e b5,rr,ee e a,v e a,nn

1pcr2ext1pcr3 bt1pcr1 sd1prc2imm

1100

2 JRNZ 4 CALL 2 JRNC 5 JRR 2 JRZ 2 JRC 4 SUB

1100

e abc e b3,rr,ee e # e a,(x)

1pcr2ext1pcr3 bt1pcr 1prc1ind

1101

2 JRNZ 4 CALL 2 JRNC 5 JRS 2 JRZ 4 INC 2 JRC 4 SUBI

1101

e abc e b3,rr,ee e w e a,nn

1pcr2ext1pcr3 bt1pcr1 sd1prc2imm

1110

2 JRNZ 4 CALL 2 JRNC 5 JRR 2 JRZ 2 JRC 4 DEC

1110

e abc e b7,rr,ee e # e (x)

1pcr2ext1pcr3 bt1pcr 1prc1ind

1111

2 JRNZ 4 CALL 2 JRNC 5 JRS 2 JRZ 4 LD 2 JRC

1111

e abc e b7,rr,ee e a,w e #

1pcr2ext1pcr3 bt1pcr1 sd1prc

Abbreviations for Addressing Modes: Leg end:

dir Direct # Indicates Illegal Instructions sd Short Direct e 5-bit Displacement imm Immediate b 3-bit Address inh I nherent rr 1-byte Data space address ext Extended nn 1-byte immediate data b.d Bit Direct abc 12-bit address bt Bit Test ee 8-bit displacement pcr Program Counter Relative ind Indirect

JRC

1prc

Mnemonic

Addressing Mode

Bytes

Cycles

Operands

ST6215C/ST6225C

62/105

Opcode Map Summary (Continued)

LOW

1000

1001

1010

1011

1100

1101

1110

1111

LOW

HI HI

0000

2 JRNZ 4 JP 2 JRNC 4 RES 2 JRZ 4 LDI 2 JRC 4 LD

0000

e abc e b0,rr e rr,nn e a,(y)

1pcr2ext1pcr2b.d1pcr3imm1prc1ind

0001

2 JRNZ 4 JP 2 JRNC 4 SET 2 JRZ 4 DEC 2 JRC 4 LD

0001

e abc e b0,rr e x e a,rr

1pcr2ext1pcr2b.d1pcr1 sd1prc2 dir

0010

2 JRNZ 4 JP 2 JRNC 4 RES 2 JRZ 4 COM 2 JRC 4 CP

0010

e abc e b4,rr e a e a,(y)

1pcr2ext1pcr2b.d1pcr 1prc1ind

0011

2 JRNZ 4 JP 2 JRNC 4 SET 2 JRZ 4 LD 2 JRC 4 CP

0011

e abc e b4,rr e x,a e a,rr

1pcr2ext1pcr2b.d1pcr1 sd1prc2 dir

0100

2 JRNZ 4 JP 2 JRNC 4 RES 2 JRZ 2 RETI 2 JRC 4 ADD

0100

e abc e b2,rr e e a,(y)

1pcr2ext1pcr2b.d1pcr1inh1prc1ind

0101

2 JRNZ 4 JP 2 JRNC 4 SET 2 JRZ 4 DEC 2 JRC 4 ADD

0101

e abc e b2,rr e y e a,rr

1pcr2ext1pcr2b.d1pcr1 sd1prc2 dir

0110

2 JRNZ 4 JP 2 JRNC 4 RES 2 JRZ 2 STOP 2 JRC 4 INC

0110

e abc e b6,rr e e (y)

1pcr2ext1pcr2b.d1pcr1inh1prc1ind

0111

2 JRNZ 4 JP 2 JRNC 4 SET 2 JRZ 4 LD 2 JRC 4 INC

0111

e abc e b6,rr e y,a e rr

1pcr2ext1pcr2b.d1pcr1 sd1prc2 dir

1000

2 JRNZ 4 JP 2 JRNC 4 RES 2 JRZ 2 JRC 4 LD

1000

e abc e b1,rr e # e (y),a

1pcr2ext1pcr2b.d1pcr 1prc1ind

1001

2 JRNZ 4 JP 2 JRNC 4 SET 2 JRZ 4 DEC 2 JRC 4 LD

1001

e abc e b1,rr e v e rr,a

1pcr2ext1pcr2b.d1pcr1 sd1prc2 dir

1010

2 JRNZ 4 JP 2 JRNC 4 RES 2 JRZ 4 RCL 2 JRC 4 AND

1010

e abc e b5,rr e a e a,(y)

1pcr2ext1pcr2b.d1pcr1inh1prc1ind

1011

2 JRNZ 4 JP 2 JRNC 4 SET 2 JRZ 4 LD 2 JRC 4 AND

1011

e abc e b5,rr e v,a e a,rr

1pcr2ext1pcr2b.d1pcr1 sd1prc2 dir

1100

2 JRNZ 4 JP 2 JRNC 4 RES 2 JRZ 2 RET 2 JRC 4 SUB

1100

e abc e b3,rr e e a,(y)

1pcr2ext1pcr2b.d1pcr1inh1prc1ind

1101

2 JRNZ 4 JP 2 JRNC 4 SET 2 JRZ 4 DEC 2 JRC 4 SUB

1101

e abc e b3,rr e w e a,rr

1pcr2ext1pcr2b.d1pcr1 sd1prc2 dir

1110

2 JRNZ 4 JP 2 JRNC 4 RES 2 JRZ 2 WAIT 2 JRC 4 DEC

1110

e abc e b7,rr e e (y)

1pcr2ext1pcr2b.d1pcr1inh1prc1ind

1111

2 JRNZ 4 JP 2 JRNC 4 SET 2 JRZ 4 LD 2 JRC 4 DEC

1111

e abc e b7,rr e w,a e rr

1pcr2ext1pcr2b.d1pcr1 sd1prc2 dir

Abbreviations for Addressing Modes: Leg end:

dir Direct # Indicates Illegal Instructions sd Short Direct e 5-bit Displacement imm Immediate b 3-bit Address inh I nherent rr 1-byte Data space address ext Extended nn 1-byte immediate data b.d Bit Direct abc 12-bit address bt Bit Test ee 8-bit Displacement pcr Program Counter Relative ind Indirect

JRC

1prc

Mnemonic

Addressing Mode

Bytes

Cycles

Operands

ST6215C/ST6225C

63/105

11 ELECTRIC AL CHARACTERISTICS

11.1 PARAMETER CONDITIONS

Unless otherwise specified, all voltages are referred to V

11.1.1 Minimum and Maximum Values

Unless otherwise specified the minimum and maximum values are guaranteed in the worst conditions of ambient t emperature, supp ly voltage an d frequencies by tests in production on 100% of the devices with an ambient temp erature at T

=25°C

and T

A=TA

max (given by the selected temperature

range). Data based on characterization results, design

simulation and/or technology characteristics are indicated in the table foo tnotes and are not tested in production. Based on characterization, the mi nimum and maximum values refer to sample tests and represent the mean value plus or minus three times the standard deviation (mean±3Σ).

11.1.2 Typical Values

Unless otherwise specified, typical data are based on T

=25°C, VDD=5V (for the 4.5V≤VDD≤6.0V

voltage range) and V

=3.3V (for the

3V≤V

≤3.6V voltage range). They are given only

as design guidelines and are not tested.

11.1.3 Typical Curves

Unless otherwise specified, all typical curves are given only as design guidelines and are not tested.

11.1.4 Loading Capacitor

The loading conditions used for pin parameter measurement is sh own in Figure 36.

Figure 36. Pin Loading Cond itions

11.1.5 Pin Input Voltage

The input voltage measurement on a pin of the device is described in Figure 37.

Figure 37. Pin In put Voltage

ST6 PIN

ST6215C/ST6225C

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11.2 ABSOLUTE MAXIMUM RATINGS

Stresses above those listed as “absolute maximum ratings” may cause permanent damage to the device. This is a stress rating only and func tional operation of the device under these cond i-

tions is not implied. Exposure to maximum rating conditions for extended periods may affect device reliabili ty.

11.2.1 Voltage Characteristi cs

11.2.2 Current Characteristics

11.2.3 Thermal Characteri stics

Notes:

1. Directly connectin g the RES ET

and I/O pins to VDD or V

could damage the dev ice if an uni ntenti onal int ernal re set is generated or an unexpected change of the I/O configuration occurs (for example, due to a corrupted program counter). To guarantee safe operation, this connection has to be done through a pull-up or pull-down resistor (typical: 4.7k

Ω

for RESET

, 10kΩ for I/Os). Unused I/O pins must be tied in the same way to VDD or VSS according to their reset con-

figuration.

2. When the current limitation is not possible , the V

absolute m aximum rating m ust be respected, otherwis e refer to

INJ(PIN)

specification. A positive injection is induced by VIN>VDD while a negative injection is induced by VIN<VSS.

3. Power (V

) and ground (VSS) lines must always be connected to the external supply.

4. Negative injection disturbs the analog performance of the device. In particular, it induces leakage currents throughout the device including the analog inputs. To avoid undesirable effects on the analog functions, care must be taken:

- Analog input pins must have a negative injection less than 1mA (assuming that the impedance of the analog voltage is lower than the specified limits).

- Pure digital pins must have a negative injection less than 1mA. In addition, it is recommended to inject the current as far as possible from the analog input pins.

Symbol Ratings Maximum value Unit

- V

Supply voltage 7

Input voltage on any pin

1) & 2)

VSS-0.3 to VDD+0.3

OUT

Output voltage on any pin

1) & 2)

VSS-0.3 to VDD+0.3

ESD(HBM)

Electro-static discharge voltage (Human Body Model)

3500

Symbol Ratings Maximum value Unit

VDD

Total current into VDD power lines (source)

VSS

Total current out of VSS ground lines (sink)

100

Output current sunk by any standard I/O and control pin 20 Output current sunk by any high sink I/O pin 40 Output current source by any I/Os and control pin 15

INJ(PIN)

2) & 4)

Injected current on RESET pin ±5 Injected current on any other pin

±5

Symbol Ratings Value Unit

STG

Storage temperature range -60 to +150 °C

Maximum junction temperature (see THERMAL CHARACTERISTICS section)

ST6215C/ST6225C

65/105

11.3 OPERATING CONDITIONS

11.3.1 General Op erating Con ditio ns

Notes:

1. An oscillator frequency above 1.2MHz is recommended for reliable A/D results.

2. Operating conditions with T

=-40 to +125°C.

Figure 38. f

OSC

Maximum Operating Frequency Versus VDD Supply Voltage for OTP & ROM devices

Symbol Parameter Conditions Min Max Unit

Supply voltage see Figure 38

3.0 6

OSC

Oscillator frequency

=3.0V, 1 & 6 Suffix 0

MHz

=3.0V, 3 Suffix 0

=3.6V, 1 & 6Suffix 0

=3.6V, 3 Suffix 0

Operating Supply Voltage

OSC

=4MHz, 1 & 6 Suffix 3.0 6.0

OSC

=4MHz, 3 Suffix 3.0 6.0

OSC

=8MHz, 1 & 6 Suffix 3.6 6.0

OSC

=8MHz, 3 Suffix 4.5 6.0

Ambient temperatur e range

1 Suffix Version 0 70

°C

6 Suffix Version -40 85 3 Suffix Version -40 125

2.5

3.6 4 4.5 5 5.5 6

SUPPLY

OSG

Min

OSC

[MHz]

FUNCTIONALITY

NOT GUARANTEED

IN THIS AREA

VOLTAGE (V

)

1. In this area, operation is guaranteed at the quartz crystal frequency.

2. When the OSG is disabled, operation in this area is guaranteed at the crystal frequency. When the

3. When the OSG is disabled, operation in this area is guaranteed at the quartz crystal frequency. When

OSG is enabled, operation in this area is guaranteed at a frequency of at least f

OSG

Min.

the OSG is enabled, access to this area is prevented. The internal frequency is kept at f

OSG

1 & 6 suffix version

3 suffix version

ST6215C/ST6225C

66/105

OPERATING CONDITIONS (Cont’d)

11.3.2 Operating Conditions with Low Voltage Detector (LVD )

Subject to general operating conditions for V

, f

OSC

, and TA.

Notes:

1. LVD typical data are based on T

=25°C. They are given only as design guidelines and are not tested.

2. The minimum V

rise time rate is needed to insure a correct device power-on and LVD reset. Not tested in production.

3. Data based on characterization results, not tested in production.

Figure 39. LVD Threshold Versus VDD and f

OSC

Figure 40. Typical LVD Thresholds Versus Temperature for OTP devices

Figure 41. Typical LVD thresholds vs. Temperature for ROM devices

Symbol Parameter Con ditions Min Typ

Max Unit

IT+

Reset release threshol d (V

rise)

3.9 4.1 4.3 V

IT-

Reset generation threshold (V

fall)

3.6 3.8 4

hys

LVD voltage threshold hysteresis V

IT+-VIT-

50 300 700 mV

POR

VDD rise time rate

mV/s

g(VDD)

Filtered glitch delay on V

Not detected by the LVD 30 ns

OSC

[MHz]

SUPPLY

2.5 3 3.5 4 4.5 5 5.5

FUNCTIONAL AREA

RESET

FUNCTIONALITY NOT GUARANTEED IN THIS AREA

IT-

≥

3.6

DEVICE UNDER

IN THIS AREA

VOLTAGE [V]

-40°C 25°C 95°C 125°C T [°C]

3.6

3.8

4.2

Thresholds [V]

Vdd up Vdd down

IT+

IT-

-40°C 25°C 95°C 125°C T [°C]

3.6

3.8

4.2

Thresholds [V]

Vdd up Vdd down

IT+

IT-

ST6215C/ST6225C

67/105

11.4 SUPPLY CURRENT CHARACTERISTICS

The following current consumption specified for the ST6 functional operating modes over temperature range does not take into account the clock source current consumption. To get the total de-

vice consumption, the two current values must be added (except for STOP mode for which the clock is stopped).

11.4.1 RUN Modes

Notes:

1. Typical data are based on T

=25°C, VDD=5V (4.5V≤V

≤

6.0V range) and V

=3.3V (3V≤V

≤

3.6V range).

2. Data based on characterization results, tested in production at V

max. and f

OSC

max.

3. CPU running with memory access, all I/O pins in input with pull-up mode (no load), all peripherals in reset state; clock input (OSC

) driven by external square wave, OSG and LVD disabled, option bytes not programmed.

Figure 42. Typical IDD in RUN vs. f

CPU

Figure 43. Typic al IDD in RUN vs. Temperature (V

= 5V)

Symbol Parameter Conditions Typ 1)Max

Unit

Supply current in RUN mode

(see Figure 42 & Figure 43)

4.5V

≤

6.0V

OSC

=32kHz

OSC

=1MHz

OSC

=2MHz

OSC

=4MHz

OSC

=8MHz

0.5

1.3

1.6

2.2

3.3

0.7

1.7

2.4

3.3

4.8 mA

Supply current in RUN mode

(see Figure 42 & Figure 43)

≤

3.6V

OSC

=32kHz

OSC

=1MHz

OSC

=2MHz

OSC

=4MHz

OSC

=8MHz

0.3

0.6

0.9

1.0

1.8

0.4

0.8

1.2

1.5

2.3

3456

VDD [V]

IDD [mA]

8MHz 4MHz 2MHz

1MHz 32KHz

-40 25 95 125

T[°C]

0.5

1.5

2.5

3.5

IDD [mA]

8MHz 4MHz 2MHz

1MHz 32KHz

ST6215C/ST6225C

68/105

SUPPLY CURRENT CHARACTERISTICS (Cont’d)

11.4.2 WAIT Modes

Notes:

1. Typical data are based on T

=25°C, VDD=5V (4.5V≤V

≤

6.0V range) and V

=3.3V (3V≤V

≤

3.6V range).

2. Data based on characterization results, tested in production at V

max. and f

OSC

max.

3. All I/O pins in input with pull-up mode (no load) , all peripherals in reset stat e; clock input (OSC

) driven by external

square wave, OSG and LVD disabled.

Symbol Parameter Conditions Typ

Max

Unit

Supply current in WAIT mode

Option bytes not programmed (see Figure 44)

4.5V

≤

6.0V OTP devices

OSC

=32kHz

OSC

=1MHz

OSC

=2MHz

OSC

=4MHz

OSC

=8MHz

330 350 370 410 480

550 600 650 700 800

µA

Supply current in WAIT mode

Option bytes programmed to 00H (see Figure 45)

OSC

=32kHz

OSC

=1MHz

OSC

=2MHz

OSC

=4MHz

OSC

=8MHz

18 26 41 57 70

80 120 180 200

Supply current in WAIT mode

(see Figure 46)

ROM devices

OSC

=32kHz

OSC

=1MHz

OSC

=2MHz

OSC

=4MHz

OSC

=8MHz

190 210 240 280 350

300 350 400 500 600

Supply current in WAIT mode

Option bytes not programmed (see Figure 44)

≤

3.6V OTP devices

OSC

=32kHz

OSC

=1MHz

OSC

=2MHz

OSC

=4MHz

OSC

=8MHz

90 100 120 150

120 140 150 200 250

Supply current in WAIT mode

Option bytes programmed to 00H (see Figure 45)

OSC

=32kHz

OSC

=1MHz

OSC

=2MHz

OSC

=4MHz

OSC

=8MHz

8 16 18 20

30 40 50 60

100

Supply current in WAIT mode

Option bytes not programmed (see Figure 46)

ROM devices

OSC

=32kHz

OSC

=1MHz

OSC

=2MHz

OSC

=4MHz

OSC

=8MHz

60 65 80

100 130

100 110 120 150 210

ST6215C/ST6225C

69/105

SUPPLY CURRENT CHARACTERISTICS (Cont’d) Figure 44. Typical I

in WAIT vs f

CPU

and Temperature for OTP device s with option bytes not

programmed

Figure 45. Typical I

in WAIT vs f

CPU

and Temperature for OTP devices with option bytes

programm ed t o 00 H

3456

VDD [V]

100

200

300

400

500

600

700

800

IDD [µA]

8MHz 4MHz 2MHz

1M 32KHz

-40 25 95 125

T[°C]

200

300

400

500

600

700

IDD [µA]

8MHz 4MHz 2MHz

1MHz 32KHz

3456

VDD [V]

100

120

IDD [µA]

8MHz 4MHz 2MHz

1M 32KHz

-20 25 95

T[°C]

IDD [µA]

8MHz

4MHz

2MHz

1MHz 32KHz

ST6215C/ST6225C

70/105

SUPPLY CURRENT CHARACTERISTICS (Cont’d) Figure 46. Typical I

in WAIT vs f

CPU

and Temperature for ROM devices

3456

VDD [V]

100

200

300

400

500

600

IDD [µA]

8MHz 4MHz 2MHz

1M 32KHz

-20 25 95 125

T[°C]

100

150

200

250

300

350

400

450

IDD [µA]

8MHz

4MHz

2MHz

1MHz 32KHz

ST6215C/ST6225C

71/105

SUPPLY CURRENT CHARACTERISTICS (Cont’d)

11.4.3 STOP Mode

Notes:

1. Typical data are based on V

=5.0V at TA=25°C.

2. All I/O pins in input with pull- up mode (no load) , all perip herals in reset stat e, OSG a nd LVD disabled, option by tes programmed to 00H. Data based on characterization results, tested in production at V

max. and f

CPU

max.

3. Maximum STOP consumption for -40°C<Ta<90°C

4. Maximum STOP consumption for -40°C<Ta<125°C

Figure 47. T y pi ca l IDD in STOP vs Temperature for OTP devices

Figure 48. Typical IDD in STOP vs Temperatu re for ROM devices

Symbol Parameter Conditions Typ

Max Unit

Supply current in STOP mode

(see Figure 47 & Figure 48)

OTP devices 0.3

ROM devices 0.1

3456

VDD [V]

200

400

600

800

1000

1200

IDD [nA]

Ta=-40°C Ta=25°C

Ta=95°C Ta=125°C

3456

VDD [V]

500

1000

1500

IDD [nA]

Ta=-40°C Ta=25°C

Ta=95°C Ta=125°C

ST6215C/ST6225C

72/105

SUPPLY CURRENT CHARACTERISTICS (Cont’d)

11.4.4 Supply and Clock System

The previous current consumption specified for the ST6 functional operating modes over temperature range does not take into account the clock

source current consumpt ion. To get the total device consumption, the two current values must be added (except for STOP mode).

11.4.5 On-Chip Periphe ral s

Notes:

1. Typical data are based on T

=25°C.

2. Data based on characterization results, not tested in production.

3. Data based on a differential I

measurement between reset configuration (OSG and LFAO disabled) and LFAO run-

ning (also includes the OSG stand alone consumption).

4. Data based on a differential I

measurement between reset configuration with OSG disabled and OSG enabled.

5. Data based on a differential I

measurement between reset configuration with LVD disabled and LVD enabled.

6. Data based on a differential I

measurement between reset configuration (timer disabled) and timer running.

7. Data based on a differential I

measurement between reset configuration and continuous A/D conversions.

Symbol Parameter Conditions Typ

Max

Unit

DD(CK)

Supply current of RC oscillator

OSC

=32 kHz,

OSC

=1 MHz

OSC

=2 MHz

OSC

=4 MHz

OSC

=8 MHz

5.0 V

230 260 340 480

OSC

=32 kHz,

OSC

=1 MHz

OSC

=2 MHz

OSC

=4 MHz

OSC

=8 MHz

3.3 V80110 180 320

Supply current of resonator oscillator

OSC

=32 kHz,

OSC

=1 MHz

OSC

=2 MHz

OSC

=4 MHz

OSC

=8MHz

5.0 V

900 280 240 140

OSC

=32 kHz,

OSC

=1 MHz

OSC

=2 MHz

OSC

=4 MHz

OSC

=8 MHz

3.3 V

120

70 50 20 10

DD(LFAO)

LFAO supply current

5.0 V 102

DD(OSG)

OSG supply current

5.0 V 40

DD(LVD)

LVD supply current

5.0 V

170

Symbol Parameter Conditions Typ

Unit

DD(TIM)

8-bit Timer supply current

OSC

=8 MHz

5.0 V 170 µA

3.3 V 100

DD(ADC)

ADC supply current when converting

OSC

=8 MHz

5.0 V 80

3.3 V 50

ST6215C/ST6225C

73/105

11.5 CLOCK AND TIMING CHARACTERISTICS

Subject to general operating conditions for V

, f

OSC

, and TA.

11.5.1 General Tim ings

11.5.2 External Clock Source

Notes:

1. Data based on typical application software.

2. Time measured between interrupt event and interrupt vector fetch. ∆t

c(INST)

is the number of t

CPU

cycles needed to finish

the current instruction execution.

Figure 49. Typical Application with an External Clock Source

Symbol Parameter Conditions Min Typ

Max Unit

c(INST)

Instruction cycle time

245t

CPU

=8 MHz 3.25 6.5 8.125

v(IT)

Interrupt reaction time

v(IT)

= ∆t

c(INST)

+ 6

611t

CPU

=8 MHz 9.75 17.875

Symbol Parameter Conditions Min Typ Max Unit

OSCINH

OSCIN input pin high level voltage

See Figure 49

0.7xV

OSCINL

OSCIN input pin low level voltage V

0.3xV

OSCx Input leakage current V

≤

± 2

OSC

OUT

OSC

EXTERNAL

ST62XX

CLOCKSOURCE

OSCINL

OSCINH

90%

10%

Not connected

ST6215C/ST6225C

74/105

CLOCK AND TIMING CHARACTERISTICS (Cont’d)

11.5.3 Crystal and Ceramic Resonator Oscillators

The ST6 internal clock can be supplied with several different Crystal/Ceramic resonator oscillators. Only parallel resonant crystals can be used. All the information given in this pa ragraph are based on

characterization results with specified typical external components. Refer to the crystal/ceramic resonator manufacturer for more details (frequency, package, accuracy...).

Notes:

1. Resonator characteristics given by the crystal/ceramic resonator manufacturer.

2. t

SU(OSC)

is the typical oscillator start-up time measured between VDD=2.8V and the fetch of the first instruction (with a

quick V

ramp-up from 0 to 5V (<50µs).

3. The oscillator selection can be optimized in terms of supply current using an high quality resonator with small R

value.

Refer to crystal/ceramic resonator manufacturer for more details.

Figure 50. Typical Application with a Crystal or Ceramic Resonator

Symbol Parameter Conditions Typ Unit

Feedback resistor 3 MΩ

Recommended load capacitances versus equivalent crystal or ceramic resonator frequency

OSC

=32 kHz,

OSC

=1 MHz

OSC

=2 MHz

OSC

=4 MHz

OSC

=8 MHz

120

47 33 33 22

Oscillator

Typical Crystal or Ceramic Resonators

[pF]

SU(osc)

[ms]

Reference Freq. Characteristic

Ceramic

MURATA

CSB455E

455KHz

∆

OSC

=[±0.5KHz

tolerance

,±0.3%

∆

±0.5%

aging

] 220 220

CSB1000J

1MHz

∆

OSC

=[±0.5KHz

tolerance

,±0.3%

∆

±0.5%

aging

] 100 100

CSTCC2.00MG0H6

2MHz

∆

OSC

=[±0.5%

tolerance

,±0.5%

∆

±0.3%

aging

]4747

CSTCC4.00MG0H6

4MHz

∆

OSC

=[±0.5%

tolerance

,±0.3%

∆

±0.3%

aging

]4747

CSTCC8.00MG

8MHz

∆

OSC

=[±0.5%

tolerance

,±0.3%

∆

±0.3%

aging

]1515

OSC

OUT

OSC

ST62XX

RESONATOR

VDD

OSC

ST6215C/ST6225C

75/105

CLOCK AND TIMING CHARACTERISTICS (Cont’d)

11.5.4 RC Oscillator

The ST6 internal clock can be supplied with an external RC oscillator. Depending on the

NET

value, the

accuracy of the frequency is about 20%, so it may not be suitable for some applications.

Notes:

1. Data based on characterization results, not tested in production. These measurements were done with the OSCin pin unconnected (only soldered on the PCB).

2. R

NET

must have a positive temperature coefficient (ppm/°C), carbon resistors should therefore not be used.

Figure 51. Typical Application with RC Oscillator

Symbol Parameter Conditions Min Typ Max Unit

OSC

RC oscillator frequency

4.5V

≤

6.0V

NET

=22 k

Ω

NET

=47 k

Ω

NET

=100 k

Ω

NET

=220 k

Ω

NET

=470 k

Ω

7.2

5.1

3.2

1.8

0.9

8.6

5.7

3.4

1.9

0.95

6.5

3.8 2

1.1

MHz

≤

3.6V

NET

=22 k

Ω

NET

=47 k

Ω

NET

=100 k

Ω

NET

=220 k

Ω

NET

=470 k

Ω

3.7

2.8

1.8 1

0.5

4.3 3

1.9

1.1

0.55

4.9

3.3 2

1.2

0.6

NET

RC Oscillator external resistor

see Figure 52 & Figure 53 22 870 k

Ω

OSC

OUT

NET

EXTERNAL RC

CEX~9pF DISCHARGE

ST62XX

VDD

OSC

VDD

MIRROR CURRENT

ST6215C/ST6225C

76/105

CLOCK AND TIMING CHARACTERISTICS (Cont’d)

Figure 52. Typical RC Oscillato r frequency vs. V

Figure 53. Typical RC Oscillator frequency vs. Temperature (V

= 5V)

11.5.5 Oscillator Safeguard (OS G) and Low Frequen cy Auxi liary Os cillator (LFA O)

Figure 54. Typical LFAO Fr e qu e nci e s

Note:

1. Data based on characterization results.

3456

VDD [V]

fosc [MHz]

Rnet=22KOhm Rnet=47KOhm Rnet=100KOhm Rnet=220KOhm Rnet=470KOhm

-40 25 95 125

Ta [°C]

fosc [MHz]

Rnet=22KOhm Rnet=47KOhm Rnet=100KOhm Rnet=220KOhm Rnet=470KOhm

Symbol Parameter Conditions Min Typ Max Unit

LFAO

Low Frequency Auxiliary Oscillator Frequency

25° C, V

5.0 V 200 350 800 kHz

25° C, V

3.3 V 86 150 340

OSG

Internal Frequency with OSG enabled

25° C, V

4.5 V 4

MHz

25° C, V

3.3 V 2

3456

VDD [V]

100

200

300

400

500

600

fosc [kHz]

Ta=-40°C Ta=25°C Ta=125°C

ST6215C/ST6225C

77/105

11.6 MEMORY CHARACTERISTICS

Subject to general operating conditions for V

, f

OSC

, and TA unless otherwise specified.

11.6.1 RAM and Hardware Registers

11.6.2 EPROM Program Memory

Figure 55. EPROM Retention Time vs. Temperature

Notes:

1. Minimum V

supply voltage without losing data stored in RAM (in STOP mode or under RESET) or in hardware reg-

isters (only in STOP mode). Guaranteed by construction, not tested in production.

2. Data based on reliability test results and monitored in production.

3. The data retention time increases when the T

decreases, see Figure 55.

Symbol Parameter Conditions Min Typ Max Unit

Data retention

0.7 V

Symbol Parameter Conditions Min Typ Max Unit

ret

Data retention

TA=+55°C

10 years

-40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90 100 110 120

Temperature [°C]

0.1

100

1000

10000

100000

Retention time [Years]

ST6215C/ST6225C

78/105

11.7 EMC CHARACTERISTICS

Susceptibility tests are performed on a sample basis during product characterization.

11.7.1 Functional EMS

(Electro Magnetic Susceptibility) Based on a simple running application on the

product (toggling 2 LEDs through I/O ports), the product is stressed by two electro magnetic events until a failure occurs (indicated by the LEDs).

■ ESD: Electro-Static Discharge (positive and

negative) is applied on all pins of the device until a functional disturbance occurs. This test conforms with the IEC 1000-4-2 standard.

■ FTB: A Burst of Fast Transient voltage (positive

and negative) is applied to V

and VSS through a 100pF capacitor, until a functional disturbance occurs. This test conforms with the IEC 1000-44 standard.

A device reset allows normal operations to be resumed.

Notes:

1. Data based on characterization results, not tested in production.

2. The suggested 10 µF an d 0.1 µF decoupl ing capacitors on the power supply lines are proposed as a good price vs. EMC performance tradeoff. They have to be put as close as possible to the device power supply pins. Other EMC recommendations are given in other sections (I/Os, RESET, OSCx pin characteristics).

Figure 56. EMC Recommended Star Network Power Supply Con nection

Symbol Parameter Conditions Neg

Pos

Unit

FESD

Voltage limits to be applied on any I/O pin to induce a functional disturbance

5V, T

+25°C, f

OSC

8MHz

conforms to IEC 1000-4-2

-2 2 kV

FFTB

Fast transient voltage burst limits to be applied through 100pF on V

and V

pins

to induce a functional disturbance

5V, T

+25°C, f

OSC

8MHz

conforms to IEC 1000-4-4

-2.5 3

0.1 µF10 µF

ST62XX

POWER SUPPLY SOURCE

ST6 DIGITAL NOISE FILTERING (close to the MCU)

ST6215C/ST6225C

79/105

EMC CHARACTERISTICS (Cont’d)

11.7.2 Absolute Electrical Sensitivit y

Based on three different tests (ESD, LU and DLU) using specific measurement methods, the product is stressed in order to determine its performance in terms of electrical sensitivity. For more details, refer to the AN1181 application note.

11.7.2.1 Electro-Static Discharge (ESD)

Electro-Static Discharges (3 positive then 3 negative pulses separated by 1 second ) are applied to the pins of each sample according to each pin combination. The sample size depends of the number of supply pins of the device (3 parts*(n+1) supply pin). Two models are usually simulated: Human Body Model and Machine Model. This test conforms to the JESD 22-A114A/A1 15A standard. See Figure 57 and the following test sequences.

Human Body Model Test Sequence

– C

is loaded through S1 by the HV pulse gener-

ator.

– S1 switches position from generator to R. – A discharge from C

through R (body resistance)

to the ST6 occurs.

– S2 must be closed 10 to 100ms after the pulse

delivery period to ensure the ST6 is not left in charge state. S2 must be opened at least 10ms prior to the delivery of the next pulse.

Machine Model Test Sequence

– C

is loaded through S1 by the HV pulse gener-

ator. – S1 switches position from generator to ST6. – A discharge from C

to the ST6 occurs.

– S2 must be closed 10 to 100ms after the pulse

delivery period to ensure the ST6 is not left in

charge state. S2 must be opened at least 10ms

prior to the delivery of the next pulse. – R (machine resistance), in series with S2, en-

sures a slow discharge of the ST6.

Absolute Maximum Ratings

Notes:

1. Data based on characterization results, not tested in production.

Figure 57. Typical Equivalent ESD Circuits

Symbol Ratings Conditions Maximum value 1)Unit

ESD(HBM)

Electro-static discharge voltage (Human Body Model)

+25°C

2000

ESD(MM)

Electro-static discharge voltage (Machine Model)

+25°C

200

ST6

R=1500

Ω

HIGH VOLTAGE

100pF

PULSE

GENERATOR

ST6

HIGH VOLTAGE

200pF

PULSE

GENERATOR

R=10k~10MΩ

HUMAN BODY MODEL MACHINE MODEL

ST6215C/ST6225C

80/105

EMC CHARACTERISTICS (Cont’d)

11.7.2.2 Static and Dynamic Latch-Up

■ LU: 3 complementary static tests are required

on 10 parts to assess the latch-up performance. A supply overvoltage (applied to each power supply pin), a current inje ction (applied to e ach input, output and configurable I/O pin) and a power supply switch sequence are performed on each sample. This test conforms to the EIA/ JESD 78 IC latch-up standard. For more details, refer to the AN1181 application note.

■ DLU: Electro-Static Discharges (one positive

then one negative test) are applied to each pin of 3 samples when the micro is running to assess the latch-up performance in dynamic mode. Power supplies are set to the typical values, the oscillator is connected as near as possible to the pins of the micro and the component is put in reset mode. This test conforms to the IEC1000-4-2 and SAEJ1752/3 standards and is described in Figure 58. For more details, refer to the AN1181 application note.

Electrical Sensitivities

Notes:

1. Class description: A Class is an STMicroelectronics internal specification. All its limits are higher than the JEDEC specifications, that means when a device belongs to Class A it exceeds the JEDEC standard. B Class strictly covers all the JEDEC criteria (international standard).

2. Schaffner NSG435 with a pointed test finger.

Figure 58. Simplified Diagram of the ESD Generator for DLU

Symbol Parameter Conditi ons Class

LU S tatic latch- up class

+25°C

+85°C

A A

DLU Dynamic latch-up class

5V, f

OSC

4MHz, T

+25°C

RCH=50M

Ω

RD=330

Ω

150pF

ESD

HV RELAY

DISCHARGE TIP

DISCHARGE RETURNCONNECTION

GENERATOR

ST6

ST6215C/ST6225C

81/105

EMC CHARACTERISTICS (Cont’d)

11.7.3 ESD Pin Protection Strateg y

To protect an integrated circuit against ElectroStatic Discharge the stress must be c ontrolled to prevent degradation or destruction of the circuit elements. The stress generally affects the circuit elements which are conn ected to the p ads but ca n also affect the internal devices when the supply pads receive the stress. The elements to be protected must n ot re ce i ve exce ssive current, vo lt a ge or heating within their structure.

An ESD network combines the different input and output ESD protections. This network works, by allowing safe discharge paths for the pins subjected to ESD stress. Two critical ESD stress cases are presented in F igure 59 and Fi gure 60 for standard pins.

Standard Pin Protection

To protect the output structure the following elements are added:

– A diode to V

(3a) and a diode from VSS (3b)

– A protection device between V

and VSS (4)

To protect the input structure the following elements are added:

– A resistor in series with the pad (1) – A diode to V

(2a) and a diode from VSS (2b)

– A protection device between V

and VSS (4)

Figure 59. Positive Stress on a Standard Pad vs. V

Figure 60. Negative Stress on a Standard Pad vs. V

(1)

(2a)

(2b)

(4)

OUT

(3a)

(3b)

Main path Path to avoid

(1)

(2a)

(2b)

(4)

OUT

(3a)

(3b)

Main path

ST6215C/ST6225C

82/105

11.8 I/O PORT PIN CHARACTERISTICS

11.8.1 General Characteri stics

Subject to general operating conditions for V

, f

OSC

, and TA unless otherwise specified.

Figure 61. Typical R

vs. VDD with V

= V

Notes:

1. Unless otherwise specified, typical data are based on T

=25°C and VDD=5V.

2. Data based on characterization results, not tested in production.

3. Hysteresis voltage between Schmitt trigger switching levels. Based on characterization results, not tested.

4. The R

pull-up equivalent resis tor is based on a resistive transis tor. This data is based on charac terization resu lts,

not tested in production.

5. Data based on characterization results, not tested in production.

6. To generate an external interrupt, a minimum pulse width has to be applied on an I/O port pin configured as an external interrupt source.

Figure 62. Two typical Applications with unused I/O Pin

Symbol Parameter Conditions Min Typ

Max Unit

Input low level voltage

0.3xV

Input high level voltage

0.7xV

hys

Schmitt trigger voltage hysteresis

VDD=5V 200 400

=3.3V 200 400

Input leakage current

SS≤VIN≤VDD

(no pull-up configured)

0.1 1

Weak pull-up equivalent resistor

IN=VSS

VDD=5V 40 110 350

Ω

=3.3V 80 230 700

I/O input pin capacitance 5 10 pF

OUT

I/O output pin capacitance 5 10 pF

f(IO)out

Output high to low level fall time

CL=50pF Between 10% and 90%

r(IO)out

Output low to high level rise time

w(IT)in

External interrupt pulse time

CPU

3456

VDD [V]

100

150

200

250

300

350

Rpu [Khom]

Ta=-40°C Ta=25°C Ta=95°C Ta=125°C

10k

Ω

UNUSED I/O PORT

ST62XX

10k

Ω

UNUSED I/O PORT

ST62XX

ST6215C/ST6225C

83/105

I/O PORT PIN CHARACTERISTICS (Cont’d)

11.8.2 Output Driving Curren t

Subject to general operating conditions for V

, f

OSC

, and TA unless otherwise specified.

Notes:

1. The I

current sunk must always respect the absolute maximum rating specified in Section 11.2.2 and the sum of I

(I/O ports and control pins) must not exceed I

VSS

2. The I

current source mus t alwa ys res pect the a bsolu te ma ximum rati ng specifie d in S ectio n 11.2 .2 an d the sum of

(I/O ports and control pins) must not exceed I

VDD

. True open drain I/O pins does not have VOH.

Figure 63. Typical VOL at V

= 5V (standard) Figure 64. Typical VOL at V

= 5V (high-sink)

Symbol P arameter Conditions Min Max Unit

Output low level voltage for a standard I/O pin (see Figure 63 and Figure 66)

=5V

IIO=+10µA, T

≤125°C 0.1

=+3mA, T

≤125°C 0.8

=+5mA, T

≤85°C 0.8

=+10mA, T

≤85°C 1.2

Output low level voltage for a high sink I/O pin (see Figure 64 and Figure 67)

=+10µA, T

≤125°C 0.1

=+7mA, T

≤125°C 0.8

=+10mA, T

≤85°C 0.8

=+15mA, T

≤125°C 1.3

=+20mA, T

≤85°C 1.3

=+30mA, T

≤85°C 2

Output high level voltage for an I/O pin (see Figure 65 and Figure 68)

=-10µA, T

≤125°C V

-0.1

=-3mA, T

≤125°C V

-1.5

=-5mA, T

≤85°C V

-1.5

0246810

Iio [mA]

200

400

600

800

1000

Vol [mV] at Vdd=5V

Ta=-40°C

Ta=25°C

Ta=95°C

Ta=125°C

048121620

Iio [mA]

0.2

0.4

0.6

0.8

Vol [V] at Vdd=5V

Ta=-40°C

Ta=25°C

Ta=95°C

Ta=125°C

ST6215C/ST6225C

84/105

I/O PORT PIN CHARACTERISTICS (Cont’d) Figure 65. Typical V

at V

= 5V

Figure 66. Typical V

vs VDD (standard I/Os)

Figure 67. Typical V

vs VDD (high-sink I/Os)

-8 -6 -4 -2 0 Iio [mA]

3.5

4.5

Voh [V] at Vdd=5V

Ta=-40°C

Ta=25°C

Ta=95°C

Ta=125°C

3456

VDD [V]

150

200

250

300

350

Vol [mV] at Iio=2mA

Ta=-40°C

Ta=25°C

Ta=95°C

Ta=125°C

3456

VDD [V]

300

400

500

600

700

Vol [mV] at Iio=5mA

Ta=-40°C

Ta=25°C

Ta=95°C

Ta=125°C

3456

VDD [V]

0.2

0.25

0.3

0.35

0.4

0.45

0.5

0.55

Vol [V] at Iio=8mA

Ta=-40°C

Ta=25°C

Ta=95°C

Ta=125°C

3456

VDD [V]

0.4

0.6

0.8

1.2

1.4

1.6

1.8

Vol [V] at Iio=20mA

Ta=-40°C

Ta=25°C

Ta=95°C

Ta=125°C

ST6215C/ST6225C

85/105

I/O PORT PIN CHARACTERISTICS (Cont’d) Figure 68. Typical V

vs V

3456

VDD [V]

Voh [V] at Iio=-2mA

Ta=-40°C

Ta=25°C

Ta=95°C

Ta=125°C

3456

VDD [V]

Voh [V] at Iio=-5mA

Ta=-40°C

Ta=25°C

Ta=95°C

Ta=125°C

ST6215C/ST6225C

86/105

11.9 CONTROL PIN CHARACTERISTICS

11.9.1 Asynchronous RESET

Subject to general operating conditions for V

, f

OSC

, and TA unless otherwise specified.

Notes:

1. Unless otherwise specified, typical data are based on T

=25°C and VDD=5V.

2. Data based on characterization results, not tested in production.

3. Hysteresis voltage between Schmitt trigger switching levels. Based on characterization results, not tested.

4. The R

pull-up equ ivalen t res istor is ba sed on a resi stive trans istor. This data is b ased on chara cteriz ation resu lts,

not tested in production.

5. All short pulse applied on RESET

pin with a duration below t

h(RSTL)in

can be ignored.

6. The reset network protects the device against parasitic resets, especially in a noisy environment.

7. The output of the external reset circuit must have an open-drain output to drive the ST6 reset pad. Otherwise the device can be damaged when the ST6 generates an internal reset (LVD or watchdog).

Figure 69. Typical RON vs VDD with VIN=V

Symbol Parameter Condit ions Min Typ

Max Unit

Input low level voltage

0.3xV

Input high level voltage

0.7xV

hys

Schmitt trigger voltage hysteresis

200 400 mV

Weak pull-up equivalent resistor

IN=VSS

VDD=5V 150 350 900

Ω

=3.3V 300 730 1900

ESD

ESD resistor protection V

IN=VSS

VDD=5V 2.8

Ω

=3.3V

w(RSTL)out

Generated reset pulse duration

External pin or internal reset sources

CPU

h(RSTL)in

External reset pulse hold time

g(RSTL)in

Filtered glitch duration

3456

VDD [V]

100

200

300

400

500

600

700

800

900

1000

Ron [Kohm]

Ta=-40°C Ta=25°C

Ta=95°C Ta=125°C

ST6215C/ST6225C

87/105

CONTROL PIN CHARACTERISTICS (Cont’d) Figure 70. Typical Applicat io n wi t h RESET

11.9.2 NMI Pin

Subject to general operating conditions for V

, f

OSC

, and TA unless otherwise specified.

Notes:

1. Unless otherwise specified, typical data are based on T

=25°C and VDD=5V.

2. Data based on characterization results, not tested in production.

3. Hysteresis voltage between Schmitt trigger switching levels. Based on characterization results, not tested.

4. The R

pull-up

equivalent resistor is b ased on a resistive tra nsistor. Th is data is ba sed on cha racterizatio n results, n ot

tested in production.

Figure 71. Typical R

pull-up

vs. VDD with VIN=V

0.1µF

4.7k

Ω

EXTERNAL

RESET

CIRCUIT

ION

INT

COUNTER

RESET

WATCHDOG RESET

LVD RESET

INTERNAL

RESET

ESD

STOP MO DE

2048 external clock cycles

Symbol Parameter Conditions Min Typ

Max Unit

Input low level voltage

0.3xV

Input high level voltage

0.7xV

hys

Schmitt trigger voltage hysteresis

200 400 mV

pull-up

Weak pull-up equivalent resistor

IN=VSS

VDD=5V 40 100 350

Ω

=3.3V 80 200 700

3456

VDD [V]

100

150

200

250

300

Rpull-up [Kohm]

Ta=-40°C Ta=25°C

Ta=95°C Ta=125°C

ST6215C/ST6225C

88/105

CONTROL PIN CHARACTERISTICS (Cont’d)

11.10 TIMER PERIPHERAL CHARACTERISTICS

Subject to general operating conditions for V

OSC

, and TA unless otherwise specified.

Refer to I/O port characteristics for more details on the input/output alternate function characteristics (TIMER).

11.10.1 W atchdog Time r

11.10.2 8-Bit Timer

Symbol Parameter Conditions Min Typ Max Unit

w(WDG)

Watchdog time-out duration

3,072 196,608 t

INT

CPU

=4MHz 0.768 49.152 ms

CPU

=8MHz 0.384 24.576 ms

Symbol Parameter Conditions Min Typ Max Unit

EXT

Timer external clock frequency 0 f

INT

/4 MHz

Pulse width at TIMER pin

VDD>4.5V 125 ns VDD=3V 1 µs

ST6215C/ST6225C

89/105

11.11 8-BIT ADC CHARACTERISTICS

Subject to general operating conditions for V

, f

OSC

, and TA unless otherwise specified.

Notes:

1. Unless otherwise specified, typical data are based on T

=25°C and VDD=5V.

2. The ADC refers to V

and VSS.

3. Any added external serial resistor will downgrade the ADC accuracy (especially for resistance greater than 10kΩ). Data based on characterization results, not tested in production.

4. As a stabilization time for the AD converter is required, the first conversion after the enable can be wrong.

Figure 72. Typical Application with ADC

Note: ADC not present on some devices. See device summary on page 1.

Symbol Parameter Conditions Min Typ

Max Unit

OSC

Clock frequency 1.2 f

OSC

MHz

AIN

Conversion range voltage

AIN

External input resistor 10

Ω

ADC

Total convertion time

OSC

=8MHz

OSC

=4MHz

140

STAB

Stabilization time

24t

CPU

OSC

=8MHz 3.25 6.5 µs

Analog input current during conversion

1.0 µA

Analog input capacitance 2 5 pF

AINx

ST62XX

AIN

10pF

ADC

10M

Ω

r≈150

Ω

ST6215C/ST6225C

90/105

8-BIT ADC CHARACTERISTICS (Cont’d) ADC Accuracy

Notes:

1. Negative injection disturbs the analog performance of the device. In particular, it induces leakage currents throughout the device including the analog inputs. To avoid undesirable effects on the analog functions, care must be taken:

- Analog input pins must have a negative injection less than 1mA (assuming that the impedance of the analog voltage is lower than the specified limits).

- Pure digital pins must have a negative injection less than 1mA. In addition, it is recommended to inject the current as far as possible from the analog input pins.

2. Data based on characterization results over the whole temperature range, monitored in production.

Figure 73. ADC Accuracy Characteristics

Note: ADC not present on some devices. See device summary on page 1.

Symbol Parameter Conditions Min Typ. Max Unit

| Total unadjusted error

VDD=5V

OSC

=8MHz

1.2

2, fosc>1.2MHz

4, fosc>32KHz

LSB

Offset error

0.72

Gain Error

-0.31

| Differential linearity error

0.54

| Integral linearity error

1LSB

IDEAL

1LSB

IDEAL

DDAVSSA

–

256

---------------------------------------- -=

Vin (LSB

IDEAL

)

(1) Example of an actual transfer curve (2) The ideal transfer curve (3) End point correlation line

=Total Unadjusted Error: maximum deviation

between the actual and th e i deal transfer c urves.

=Offset Er ror: deviation b et ween the first actual

transition and the first ideal one.

=Gain E rror: deviation between the last ideal

transition and the last actual one.

=Differential Linearity Error: maximum deviation

between actual steps a nd t he i deal one.

=Integral Linearity Error: maximum deviation between an y actual transit ion and the e nd point correlation line.

Digit al Result AD CDR

255 254 253

5 4 3 2 1

7 6

1234567

253 2 54 255 256

(1)

(2)

(3)

DDA

SSA

ST6215C/ST6225C

91/105

12 GENERAL INFORMATION

12.1 PACKAGE MECHANICAL DATA Figure 74. 28-Pin Plastic Dual In-Line Package, 600-mil Width

Figure 75. 28-Pin Plastic Small Outline Package, 300-mil Width

Dim.

mm inches

Min Typ Max Min Typ Max

A 6.35 0.250 A1 0.38 0.015 A2 3.18 4.95 0.125 0.195

B 0.36 0.56 0.014 0.022 B1 0.76 1.78 0.030 0.070

C 0.20 0.38 0.008 0.015

D 35.05 39.75 1.380 1.565 D1 0.13 0.005

e 2.54 0.100

eB 17.78 0.700

E 15.24 15.88 0.600 0.625

E1 12.32 14.73 0.485 0.580

L 2.92 5.08 0.115 0.200

Number of Pins

N 28

E1 eB

AA2

BB1

Dim.

mm inches

Min Typ Max Min Typ Max

A 2.35 2.65 0.093 0.104 A1 0.10 0.30 0.004 0.012

B 0.33 0.51 0.013 0.020

C 0.23 0.32 0.009 0.013

D 17.70 18.10 0.697 0.713

E 7.40 7.60 0.291 0.299 e 1.27 0.050

H 10.00 10.65 0.394 0.419

h 0.25 0.75 0.010 0.030

0° 8° 0° 8°

L 0.40 1.27 0.016 0.050

Number of Pins

N 28

h x 45×

ST6215C/ST6225C

92/105

PACKAGE MECHANICAL DATA (Cont’d) Figure 76. 28-Pin Ceramic Side-Brazed Dual In-Line Package

Figure 77. 28-Pin Plastic Shrink Small Outline Package

Dim.

mm inches

Min Typ Max Min Typ Max

A 4.17 0.164

A1 0.76 0.030

B 0.36 0.46 0.56 0.014 0.018 0.022

B1 0.76 1.27 1.78 0.030 0.050 0.070

C 0.20 0.25 0.38 0.008 0.010 0.015

D 34.95 35.56 36.17 1.376 1.400 1.424 D1 33.02 1.300 E1 14.61 15.11 15.62 0.575 0.595 0.615

e 2.54 0.100

G 12.70 12.95 13.21 0.500 0.510 0.520 G1 12.70 12.95 13.21 0.500 0.510 0.520 G2 1.14 0.045

L 2.92 5.08 0.115 0.200

S 1.27 0.050

Ø 8.89 0.350

Number of Pins

N28

CDIP28W

Dim.

mm inches

Min Typ Max Min Typ Max

A 2.00 0.079 A1 0.05 0.002 A2 1.65 1.75 1.85 0.065 0.069 0.073

b 0.22 0.38 0.009 0.015 c 0.09 0.25 0.004 0.010

D 9.90 10.20 10.50 0.390 0.402 0.413

E 7.40 7.80 8.20 0.291 0.307 0.323

E1 5.00 5.30 5.60 0.197 0.209 0.220

e 0.65 0.026

0° 4° 8° 0° 4° 8°

L 0.55 0.75 0.95 0.022 0.030 0.037

Number of Pins

N 28

E1 E

ST6215C/ST6225C

93/105

12.2 THERMAL CHARACTERISTICS

Notes:

1. The power dissipation is obtained from the formula P

= P

INT

+ P

PORT

where P

INT

is the chip internal power (IDDxVDD)

and P

PORT

is the port power dissipation determined by the user.

2. The average chip-junction temperature can be obtained from the formula T

= TA + PD x RthJA.

Symbol Ratings Value Unit

thJA

Package thermal resistance (junction to ambient) DIP28 SO28 SSOP28

55 75

110

°C/W

Power dissipation

500 mW

Jmax

Maximum junction temperature

150 °C

ST6215C/ST6225C

94/105

12.3 SOLDERING AND GLUEABILITY INFORMATION

Recommended soldering information given only as design guidelines in Figure 78 and Figure 79 .

Recommended glue for SMD plastic packages:

■ Heraeus: PD945, PD955

■ Loctite: 3615, 3298

Figure 78. Recommended Wave Soldering Profile (with 37% Sn and 63% Pb)

Figure 79. R ec o m m ended Reflow Soldering Oven Prof ile ( MI D J ED EC)

250

200

150

100

40 80

120 160

Time [sec]

Temp. [°C]

20 60

100 140

5 sec

COOLING PHA SE (ROOM TEMPE RAT URE)

PREHEATING

80°C

PHASE

SOLDERING PHASE

250

200

150

100

100 200

300 400

Time [sec]

Temp. [°C]

ramp up

2°C/sec for 50sec

90 sec at 125°C

150 sec above 183°C

ramp down natural 2°C/sec max

Tmax=220+/-5°C for 25 sec

ST6215C/ST6225C

95/105

12.4 PACKAGE/SOCKET FOOTPRINT PROPOSAL Table 22. Suggested List of DIP28 Socket Types

Table 23. Suggested List of SO28 Socket Typ es

Table 24. Suggested List of SSOP28 Socket Types

Package / Probe Adaptor / Socket Reference

Same

Footprint

Socket Type

DIP28 TEXTO OL 228-60-23 X Te xtool

Package / Probe Adaptor / Socket Reference

Same

Footprint

Socket Type

SO28

ENPLAS OTS-28-1.27-04 Open Top YAMAICHI IC51-0282-334-1 Clamshell

EMU PROBE

Adapter from SO28 to DIP28 footprint (delivered with emulator)

X SMD to DIP

Programming Adapter

Logical Systems PA28SO1-08-6 X Open Top

Package / Probe Adaptor / Socket Reference

Same

Footprint

Socket Type

SSOP28 ENPLAS OTS-28-0.65-01 Open Top EMU PROBE

Adapter from SSOP28 to DIP28 footprint (sales type: ST626X-P /SSO P28)

X DIP to SMD

Programming Adapter

Logical Systems PA28SS-OT-6 X Open Top

ST6215C/ST6225C

96/105

12.5 ORDERING INFORMATION

The following section deals with the procedure for transfer of customer codes to STMicroelect ronics

and also details the ST6 factory coded device type.

Figure 80. ST6 Factory Coded Device Types

ROM code

Temperature code:

1: Standard 0 to +70 °C 3: Automotive -40 to +125 °C 6: Industrial -40 to +85 °C

Package type:

B: Plastic DIP D: Ceramic DIP M: Plastic SOP N: Plastic SSOP T: Plastic TQFP

Revision index:

B,C: Product Definition change L: Low Voltage Device

ST6 Sub family Version Code:

No char: ROM E: EPROM P: FASTROM T: OTP

Family

ST62T25CB6/CCC

ST6215C/ST6225C

97/105

12.6 TRANSFER OF CUSTOMER CODE

Customer code is made up of the RO M contents and the list of the selected FASTROM options. The ROM contents are to be sent on diskette, or by electronic means, with the hexadecimal file generated by the development tool. All unused bytes must be set to FFh.

The selected options are communicated to STMicroelectronics using the correctly filled OPTION LIST appended.

The STMicroelectronics Sales Organization will be pleased to provide detailed information on contractual points.

Listing Generation and Verification. When

STMicroelectronics receives the user’s ROM contents, a computer listing is generated from it. This listing refers exactly to the ROM contents and options which will be used t o produce the specified MCU. The listing is then returned to the custom er who must thoroughly check, complete, sign and return it to STMicroelectronics. The signed listing forms a part of the contractual agreement for the production of the specific customer MCU.

12.6.1 FASTROM Version The ST62P15C/P25C are the Fact ory Advanced

Service Technique ROM (FASTROM) versions of

ST62T15C,T25C OTP devices.

They offer the same functionality as OTP devices, but they do not have to be programmed by the customer. The customer code must be sent to STMicroelectronics in the same way as for ROM devices. The FASTR OM option list has the same options as defined in the programmable option byte of the OTP version . It also of fers an identifier option. If this option is enabled, each FASTROM device is programmed with a unique 5-byte number which is mapped at addresses 0F9Bh0F9Fh. The user must therefore leave these bytes blanked.

The identification number is structured as follows:

with T0, T1, T2, T3 = time in seconds since 01/01/ 1970 and Test ID = Tester Identifier.

0F9Bh T 0 0F9Ch T1 0F9Dh T2 0F9Eh T 3

0F9Fh Test ID

ST6215C/ST6225C

98/105

TRANSFER OF CUSTOMER CODE (Cont’d)

12.6.2 ROM Version

The ST6215C/25C are mask programmed ROM version of ST62T15C,T25C OTP devices.

They offer the same functionality as OTP devices, selecting as ROM options the options def ined in the programmable option byte of the OTP version.

Figure 81. Programming Circuit

Note: ZPD15 is used for overvoltage protection

ROM Readout Protection. If th e ROM READOUT

PROTECTION option is selected, a protection fuse can be blown to prevent any access to the program memory content.

In case the user wants to blow this fuse, high voltage must be applied on the V

pin.

Figure 82. Programm ing wave form

VR02003

100nF

4.7µF

PROTECT

100nF

ZPD15 15V

14V

100 µs max

0.5s min

14V typ

400mA

4mA typ

VR02001

max

150 µs typ

ST6215C/ST6225C

99/105

ST6215C/25C/P15C/P25C MICROCONTROLLER OPTION LIST

Customer: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Address: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Contact: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Phone: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Reference: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

STMicroelectronics references:

Device: [ ] ST6215C (2 KB) [ ] ST6225C (4 KB)

[ ] ST62P15C (2 KB) [ ] ST62P25C (4 KB)

Package: [ ] Dual in Line Plastic

[ ] Small Outline Plastic with conditioning

[ ] Shrink Small Outline Plastic with conditioning Conditioning option: [ ] Standard (Tube) [ ] Tape & Reel Temperature Range: [ ] 0°C to + 70°C [ ] - 40°C to + 85°C

[ ] - 40°C to + 125°C

Marking: [ ] Standard marking [ ] Special marking (ROM only): PDIP28 (10 char. max): _ _ _ _ _ _ _ _ _ _

PSO28 (8 char. max): _ _ _ _ _ _ _ _

SSOP28 (11 char. max): _ _ _ _ _ _ _ _ _ _ _

Authorized characters are letters, digits, '.', '-', '/' and spaces only.

Oscillator Safeguard: [ ] Enabled [ ] Disabled Watchdog Selection: [ ] Software Activation [ ] Hardware Activation Timer pull-up: [ ] Enabled [ ] Disabled NMI pull-up: [ ] Enabled [ ] Disabled Oscillator Selection: [ ] Quartz crystal / Ceramic resonator

[ ] RC network

Readout Protection: FASTROM:

[ ] Enabled [ ] Disabled

ROM:

[ ] Enabled:

[ ] Fuse is blown by STMicroelectronics [ ] Fuse can be blown by the customer

[ ] Disabled

Low Voltage Detector: [ ] Enabled [ ] Disabled External STOP Mode Control: [ ] Enabled [ ] Disabled Identifier (FASTROM only): [ ] Enabled [ ] Disabled

Comments:

Oscillator Frequency in the application: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Supply Operating Range in the application: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Notes: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Date: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Signature: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

ST6215C/ST6225C

100/105

13 DEVELOPMENT TOOLS

STMicroelectronics offers a range of hardware and software development tools for the ST6 microcontroller family. Full details of tools available for the ST6 from third party manufacturers can be ob-

tain from the STMicroelectronics Internet site: ➟ http://m cu .st.com.

Table 25. Dedicated Third Parties Development Tools

Note 1: For latest information on third party tools, please visit our Internet site: ➟ http://mcu.st.com .

Third Party

Designation ST Sales Type Web site address

ACTUM

ST-REALIZER II: Graphical Schematic based Development available from STMicroelectronics.

STREALIZER-II

http://www.actum.com/

CEIBO

Low cost emulator available from CEIBO.

http://www.ceibo.com/

RAISONANCE

This tool includes in the same environment: an assembler, linker, C compiler, debugger and simulator. The assembler package (plus limited C compiler) is free and can be downloaded from raisonance web site. The full version is available both from STMicroelectronics and Raisonance.

ST6RAIS-SWC/

http://www.raisonance.com/

SOFTEC

High end emulator available from SOFTEC.

http://www.softecmicro.com/

Gang programmer available from SOFTEC.

ADVANCED EQUIPMENT

Single and gang programmers

http://www.aec.com.tw/

ADVANCED TRANSDATA http://www.adv-transdata.com/

BP MICROSYSTEMS http://www.bpmicro.com/

DATA I/O

http://www.data-io.com/

DATAMAN http://www.dataman.com/ EE TOOLS http://www.eetools.com/

ELNEC

http://www.elnec.com/

HI-LO SYSTEMS

http://www.hilosystems.com.tw/

ICE TECHNOLOGY http://www.icetech.com/

LEAP http://www.leap.com.tw/

LLOYD RESEARCH

http://www.lloyd-research.com/

LOGICAL DEVICES

http://www.chipprogram-

mers.com /

MQP ELECTRONICS

http://www.mqp.com/

NEEDHAMS

ELECTRONIC S

http://www.needhams.co m /

STAG PROGRAMMERS http://www.stag.co.uk/

SYSTEM GENERAL CORP

http://www.sg.com.tw

TRIBAL MICROSYSTEMS

http://www.tribalmicro.com/

XELTEK http://www.xeltek.com/

Datasheet ST62T25BN3, ST62T25BN1, ST62T25BM6, ST62T25BM3, ST62T25BM1 Datasheet (SGS Thomson Microelectronics)

Specifications and Main Features

Frequently Asked Questions

User Manual