– Maximum Core Frequency 48 MHz in X1 Mode, 24 MHz in X2 Mode
– Dual Data Pointer
– Full-duplex Enhanced UART (EUART)
– Three 16-bit Timer/Counters: T0, T1 and T2
– 256 Bytes of Scratchpad RAM
• 16/32-Kbyte On-chip Flash EEPROM In-System Programmi
– Byte and Page (128 bytes) Erase and Write
– 100k Write Cycles
• 3-KbyteFlash EEPROM for Bootloader
– Byte and Page (128 bytes) Erase and Write
– 100k Write Cycles
• 1-Kbyte EEPROM Data (
– Byte and Page (128 bytes) Erase and Write
– 100k Write Cycles
• On-chip Expanded RAM (ERAM): 1024 Bytes
• Integrated Power Monitor (POR/PFD) to Supervise Internal Power Supply
• USB 1.1 and 2.0 Full Speed Compliant Module with Interrupt on Transfer Completion
– Endpoint 0 for Control Transfers: 32-byte FIFO
– 6 Programmable Endpoints with In or Out Directions and with Bulk, Interrupt or
Isochronous Transfers
• Endpoint 1, 2, 3: 32-byte FIFO
• Endpoint 4, 5: 2 x 64-byte FIFO with Double Buffering (Ping-pong Mode)
• Endpoint 6: 2 x 512-byte FIFO with Double Buffering (Ping-pong Mode)
– Suspend/Resume Interrupts
– 48 MHz PLL for Full-speed Bus Operation
– Bus Disconnection on Microcontroller Request
• 5 Channels Programmable Counter Array (PCA) with 16-
Output, Compare/Capture, PWM and Watchdog Timer Capabilities
• Programmable Hardware Watchdog Timer (One-time Enabled with Reset-out): 100 ms
to 3s at 8 MHz
• Keyboard Interrupt Interface on Port P1 (8 Bits)
• TWI (Two Wire Interface) 400Kbit/s
• SPI Interface (Master/Slave Mode)
• 34 I/O Pins
• 4 Direct-drive LED Outputs with Programmable Current Sources: 2-6-10 mA Typical
• 4-level Priority Interrupt System (11 sources)
• Idle and Power-down Modes
• 0 to 24 MHz On-chip Oscillator with Analog PLL for 48 MHz Synthesis
• Industrial Temperature Range
• Extended Range Power Supply: 2.7V to 5.5V (3.3V to 5.5V required for USB)
• Packages: PLCC52, VQFP64, QFN32
ng through USB
bit Counter, High-speed
8-bit Flash
Microcontroller
with Full Speed
USB Device
AT89C5130A-M
AT89C5131A-M
AT89C5130A/31A-M
1.Description
AT89C5130A/31A-M is a high-performance Flash version of the 80C51 single-chip 8-bit microcontrollers with full speed USB functions.
AT89C5130A/31A-M features a full-speed USB module compatible with the USB specifications
Version 1.1 and 2.0. This module integrates the USB transceivers with a 3.3V voltage regulator
and the Serial Interface Engine (SIE) with Digital Phase Locked Loop and 48 MHz clock recovery. USB Event detection logic (Reset and Suspend/Resume) and FIFO buffers supporting the
m a n d a to ry c o n tr ol E nd po in t ( E P0 ) a n d u p t o 6 v er sa ti le E nd po i n t s
(EP1/EP2/EP3/EP4/EP5/EP6) with minimum software overhead are also part of the USB
module.
AT89C5130A/31A-M retains the features of the Atmel 80C52 with extended Flash capacity
(16/32-Kbytes), 256 bytes of internal RAM, a 4-level interrupt system, two 16-bit timer/counters
(T0/T1), a full duplex enhanced UART (EUART) and an on-chip oscillator.
In addition, AT89C5130A/31A-M has an on-chip expanded RAM of 1024 bytes (ERAM), a dual
data pointer, a 16-bit up/down Timer (T2), a Programmable Counter Array (PCA), up to 4 programmable LED current sources, a programmable hardware watchdog and a power-on reset.
AT89C5130A/31A-M has two software-selectable modes of reduced activity for further reduction
in power consumption. In the idle mode the CPU is frozen while the timers, the serial ports and
the interrupt system are still operating. In the power-down mode the RAM is saved, the peripheral clock is frozen, but the device has full wake-up capability through USB events or external
interrupts.
2
4337K–USB–04/08
2.Block Diagram
Timer 0
INT
RAM
256x8
T0
T1
RxD
TxD
WR
RD
EA
PSEN
ALE
XTAL2
XTAL1
EUART
CPU
Timer 1
INT1
Ctrl
INT0
(2)
(2)
C51
CORE
(2) (2)(2) (2)
Port 0P0Port 1
Port 2
Port 3
Parallel I/O Ports & Ext. Bus
P1
P2
P3
ERAM
1Kx8
PCA
RST
Watch
Dog
CEX
ECI
VSS
VDD
(2)(2)
(1)(1)
Timer2
T2EX
T2
(1) (1)
Port 4
P4
16/32Kx8Flash
+
BRG
USB
D -
D +
VREF
Regu-
Key
Board
KIN [0..7]
lator
AVSS
EEPROM
4Kx8
SPI
MISO
MOSI
SCK
(1) (1) (1)
SS
(1)
AVDD
TWI
SCL
SDA
(3) (3)
AT89C5130A/31A-M
Notes:1. Alternate function of Port 1
2. Alternate function of Port 3
3. Alternate function of Port 4
4337K–USB–04/08
3
AT89C5130A/31A-M
3.Pinout Description
21 222625242329282730 31
5 4 3 2 1 6
52 51 50 49 48
8
9
10
11
12
13
14
15
16
17
18
46
45
44
43
42
41
40
39
38
37
36
PLCC52
7 47
19
20
32 33
34
35
P1.1/T2EX/KIN1/SS
P1.0/T2/KIN0
P0.6/AD6
ALE
P0.7/AD7
EA
PSEN
P1.7/CEX4/KIN7/MOSI
P1.3/CEX0/KIN3
P1.5/CEX2/KIN5/MISO
P1.6/CEX3/KIN6/SCK
PLLF
P3.0/RxD
AVSS
P2.6/A14
XTAL1
P2.5/A13
P0.3/AD3
P0.5/AD5
P0.4/AD4
VREF
P0.2/AD2
P0.0/AD0
P0.1/AD1
AVDD
UCAP
P3.2/INT0
P3.6/WR/LED2
XTAL2
RST
P3.1/TxD
P3.3/INT1/LED0
P3.7/RD/LED3
D-
P2.0/A8
P2.1/A9
P2.2/A10
P2.3/A11
VSS
P2.4/A12
P4.1/SDA
D+
P4.0/SCL
P1.2/ECI/KIN2
P1.4/CEX1/KIN4
P3.4/T0
P3.5/T1/LED1
NC
NC
VDD
UVSS
P2.7/A15
3.1Pinout
Figure 3-1.AT89C5130A/31A-M 52-pin PLCC Pinout
4
4337K–USB–04/08
Figure 3-2.AT89C5130A/31A-M 64-pin VQFP Pinout
17 182221201925242326 27
62 61 60 59 58 63
57 56 55 54 53
1
2
3
4
5
6
7
8
9
10
11
48
47
46
45
44
43
42
41
40
39
38
VQFP64
64
52
12
13
28
29
36
37
51 50
49
35
33
34
14
15
16
30
31 32
P1.1/T2EX/KIN1/SS
ALE
EA
PSEN
P1.7/CEX4/KIN7/MOSI
P1.3/CEX0/KIN3
P1.5/CEX2/KIN5/MISO
P1.6/CEX3/KIN6/SCK
P2.7/A15
P2.6/A14
P4.1/SDA
P1.2/ECI/KIN2
P1.4/CEX1/KIN4
P1.0/T2/KIN0
PLLF
UCAP
XTAL2
RST
P3.7/RD/LED3
P2.0/A8
P2.1/A9
P2.2/A10
P2.3/A11
P2.4/A12
NC
NC
P3.0/RxD
NC
VREF
P0.0/AD0
AVSS
P3.2/INT0
P3.6/WR/LED2
P3.1/TxD
P3.3/INT1/LED0
VSS
P3.4/T0
P3.5/T1/LED1
NC
P0.6/AD6
P0.7/AD7
P2.5/A13
P0.3/AD3
P0.5/AD5
P0.4/AD4
P0.2/AD2
P0.1/AD1
D-
D+
P4.0/SCL
XTAL1
AVDD
NC
NC
NC
NC
UVSS
NC
NC
NC
NC
NC
NC
VDD
AT89C5130A/31A-M
4337K–USB–04/08
5
AT89C5130A/31A-M
Figure 3-3.AT89C5130A/31A-M 32-pin QFN Pinout
1
2
3
4
5
6
QFN32
7
P1.1/T2EX/KIN1/SS
P1.7/CEX4/KIN7/MOSI
P1.3/CEX0/KIN3
P1.5/CEX2/KIN5/MISO
P1.6/CEX3/KIN6/SCK
P3.0/RxD
AVSS
XTAL1
VREF
UCAP
P3.2/INT0
P3.5/T1/LED1
XTAL2
RST
P3.1/TxD
P3.3/INT1/LED0
P3.7/RD/LED3
D-
VSS
P4.1/SDA
D+
P4.0/SCL
P1.2/ECI/KIN2
P1.4/CEX1/KIN4
P3.4/T0
P1.0/T2/KIN0
VDD
8
PLLF
P3.6/WR/LED2
UVSS
NC
NC
24
23
22
21
20
19
18
17
9 10 11 12 13 14 15 16
32 31 30 29 28 27 26 25
Note : The metal plate can be connected to Vss
3.2Signals
6
All the AT89C5130A/31A-M signals are detailed by functionality on Table 3-1 through Table 3-
12.
Table 3-1.Keypad Interface Signal Description
Signal
NameType Description
Table 3-2.Programmable Counter Array Signal Description
KIN[7:0)I
Signal
NameType Description
ECIIExternal Clock InputP1.2
Keypad Input Lines
Holding one of these pins high or low for 24 oscillator periods triggers a
keypad interrupt if enabled. Held line is reported in the KBCON register.
Alternate
Function
P1[7:0]
Alternate
Function
4337K–USB–04/08
AT89C5130A/31A-M
Signal
NameType Description
Capture External Input
CEX[4:0]I/O
Compare External Output
Table 3-3.Serial I/O Signal Description
Signal
NameType Description
RxDISerial Input PortP3.0
TxDOSerial Output PortP3.1
Table 3-4.Timer 0, Timer 1 and Timer 2 Signal Description
Signal
NameType Description
Timer 0 Gate Input
INT0 serves as external run control for timer 0, when selected by GATE0
bit in TCON register.
INT0I
External Interrupt 0
INT0 input set IE0 in the TCON register. If bit IT0 in this register is set, bits
IE0 are set by a falling edge on INT0. If bit IT0 is cleared, bits IE0 is set by
a low level on INT0.
Alternate
Function
P1.3
P1.4
P1.5
P1.6
P1.7
Alternate
Function
Alternate
Function
P3.2
Timer 1 Gate Input
serves as external run control for Timer 1, when selected by GATE1
INT1
bit in TCON register.
INT1I
T0I
T1I
T2
T2EXITimer/Counter 2 Reload/Capture/Direction Control InputP1.1
External Interrupt 1
INT1 input set IE1 in the TCON register. If bit IT1 in this register is set, bits
IE1 are set by a falling edge on INT1. If bit IT1 is cleared, bits IE1 is set by
a low level on INT1.
Timer Counter 0 External Clock Input
When Timer 0 operates as a counter, a falling edge on the T0 pin
increments the count.
Timer/Counter 1 External Clock Input
When Timer 1 operates as a counter, a falling edge on the T1 pin
increments the count.
IOTimer/Counter 2 External Clock Input
Timer/Counter 2 Clock Output
P3.3
P3.4
P3.5
P1.0
4337K–USB–04/08
7
AT89C5130A/31A-M
Table 3-5.LED Signal Description
Signal
NameTypeDescription
Direct Drive LED Output
LED[3:0]O
These pins can be directly connected to the Cathode of standard LEDs
without external current limiting resistors. The typical current of each
output can be programmed by software to 2, 6 or 10 mA. Several outputs
can be connected together to get higher drive capabilities.
Table 3-6.TWI Signal Description
Signal
NameTypeDescription
SCLI/O
SDAI/O
SCL: TWI Serial Clock
SCL output the serial clock to slave peripherals.
SCL input the serial clock from master.
SDA: TWI Serial Data
SCL is the bidirectional TWI data line.
Table 3-7.SPI Signal Description
Signal
NameType Description
SSI/OSS
: SPI Slave SelectP1.1
Alternate
Function
P3.3
P3.5
P3.6
P3.7
Alternate
Function
P4.0
P4.1
Alternate
Function
MISOI/O
SCKI/O
MOSI
I/O
MISO: SPI Master Input Slave Output line
When SPI is in master mode, MISO receives data from the slave
peripheral. When SPI is in slave mode, MISO outputs data to the master
controller.
SCK: SPI Serial Clock
SCK outputs clock to the slave peripheral or receive clock from the master
MOSI: SPI Master Output Slave Input line
When SPI is in master mode, MOSI outputs data to the slave peripheral.
When SPI is in slave mode, MOSI receives data from the master controller
P1.5
P1.6
P1.7
8
4337K–USB–04/08
Table 3-8.Ports Signal Description
Signal
NameTypeDescriptionAlternate Function
Port 0
P0 is an 8-bit open-drain bidirectional I/O port. Port 0
P0[7:0]I/O
P1[7:0]I/O
pins that have 1s written to them float and can be used
as high impedance inputs. To avoid any parasitic current
consumption, Floating P0 inputs must be pulled to V
.
V
SS
Port 1
P1 is an 8-bit bidirectional I/O port with internal pull-ups.
AT89C5130A/31A-M
AD[7:0]
or
DD
KIN[7:0]
T2
T2EX
ECI
CEX[4:0]
P2[7:0]I/O
P3[7:0]I/O
P4[1:0]I/O
Port 2
P2 is an 8-bit bidirectional I/O port with internal pull-ups.
Port 3
P3 is an 8-bit bidirectional I/O port with internal pull-ups.
Port 4
P4 is an 2-bit open drain port.
Table 3-9.Clock Signal Description
Signal
NameType Description
XTAL1I
XTAL2O
Input to the on-chip inverting oscillator amplifier
To use the internal oscillator, a crystal/resonator circuit is connected to this
pin. If an external oscillator is used, its output is connected to this pin.
Output of the on-chip inverting oscillator amplifier
To use the internal oscillator, a crystal/resonator circuit is connected to this
pin. If an external oscillator is used, leave XTAL2 unconnected.
A[15:8]
LED[3:0]
RxD
TxD
INT0
INT1
T0
T1
WR
RD
SCL
SDA
Alternate
Function
-
-
4337K–USB–04/08
PLLFI
PLL Low Pass Filter input
Receive the RC network of the PLL low pass filter.
-
9
AT89C5130A/31A-M
Table 3-10.USB Signal Description
Signal
NameType Description
D+I/O
D-I/O
VREFO
USB Data + signal
Set to high level under reset.
USB Data - signal
Set to low level under reset.
USB Reference Voltage
Connect this pin to D+ using a 1.5 kΩ resistor to use the Detach function.
Table 3-11.System Signal Description
Signal
NameType Description
AD[7:0]I/O
A[15:8]I/OAddress Bus MSB for external accessP2[7:0]
RD
WRI/O
Multiplexed Address/Data LSB for external access
Data LSB for Slave port access (used for 8-bit and 16-bit modes)
Read Signal
Read signal asserted during external data memory read operation.
I/O
Control input for slave port read access cycles.
Write Signal
Write signal asserted during external data memory write operation.
Control input for slave write access cycles.
Alternate
Function
-
-
-
Alternate
Function
P0[7:0]
P3.7
P3.6
Reset Input
Holding this pin low for 64 oscillator periods while the oscillator is running
resets the device. The Port pins are driven to their reset conditions when a
voltage lower than V
RSTO
ALEO
PSENI/O
EAI
This pin has an internal pull-up resistor which allows the device to be reset
by connecting a capacitor between this pin and VSS.
Asserting RST when the chip is in Idle mode or Power-down mode returns
the chip to normal operation.
This pin is tied to 0 for at least 12 oscillator periods when an internal reset
occurs ( hardware watchdog or power monitor).
Address Latch Enable Output
The falling edge of ALE strobes the address into external latch. This signal
is active only when reading or writing external memory using MOVX
instructions.
Program Strobe Enable / Hardware conditions Input for ISP
Used as input under reset to detect external hardware conditions of ISP
mode.
External Access Enable
This pin must be held low to force the device to fetch code from external
program memory starting at address 0000h.
Table 3-12.Power Signal Description
Signal
NameType Description
is applied, whether or not the oscillator is running.
IL
-
-
-
-
Alternate
Function
10
AVSSGND
Analog Ground
AVSS is used to supply the on-chip PLL and the USB PAD.
-
4337K–USB–04/08
Table 3-12.Power Signal Description (Continued)
Signal
NameType Description
AT89C5130A/31A-M
Alternate
Function
AVDDPWR
VSSGND
UVSSGND
UCAPPWR
VDDPWR
VREFO
Analog Supply Voltage
AVDD is used to supply the on-chip PLL and the USB PAD.
Digital Ground
VSS is used to supply the buffer ring and the digital core.
USB Digital Ground
UVSS is used to supply the USB pads.
USB Pad Power Capacitor
UCAP must be connect to an external capacitor for USB pad power supply
(for typical application see
Digital Supply Voltage
VDD is used to supply the buffer ring on all versions of the device.
It is also used to power the on-chip voltage regulator of the Standard
versions or the digital core of the Low Power versions.
USB pull-up Controlled Output
VREF is used to control the USB D+ 1.5 kΩ pull up.
The Vref output is in high impedance when the bit DETACH is set in the
USBCON register.
Figure 4-1 on page 12)
-
-
-
-
-
-
4337K–USB–04/08
11
AT89C5130A/31A-M
4.Typical Application
VSS
XTAL1
XTAL2
Q
22pF
22pF
VSS
PLLF
100R
10nF
2.2nF
VSS
VSS
AVSS
VSS
D-
UCAP
1µF
VSS
D+
27R
27R
VRef
1.5K
USB
D+
D-
VBUS
GND
VSS
VDD
AVDD
VDD
VDD
4.7µF
VSS
100nF
VSS
100nF
VSS
UVSS
AT89C5130A/31A-M
+20%
4.1Recommended External components
All the external components described in the figure below must be implemented as close as possible from the microcontroller package.
The following figure represents the typical wiring schematic.
Figure 4-1.Typical Application
12
4337K–USB–04/08
4.2PCB Recommandations
D+
VRef
D-
USB Connector
Wires must be routed in Parallel and
Components must be
If possible, isolate D+ and D- signals from other signals
with ground wires
must be as short as possible
close to the
microcontroller
PLLFAVss
Components must be
Isolate filter components
with a ground wire
microcontroller
close to the
C2
C1
R
Figure 4-2.USB Pads
Figure 4-3.USB PLL
AT89C5130A/31A-M
4337K–USB–04/08
13
AT89C5130A/31A-M
5.Clock Controller
X1
X2
PD
PCON.1
IDL
PCON.0
Peripheral
CPU Core
0
1
X2
CKCON.0
÷
2
Clock
Clock
EXT48
PLLCON.2
0
1
PLL
USB
Clock
5.1Introduction
The AT89C5130A/31A-M clock controller is based on an on-chip oscillator feeding an on-chip
Phase Lock Loop (PLL). All the internal clocks to the peripherals and CPU core are generated
by this controller.
The AT89C5130A/31A-M X1 and X2 pins are the input and the output of a single-stage on-chip
inverter (see Figure 5-1) that can be configured with off-chip components as a Pierce oscillator
(see Figure 5-2). Value of capacitors and crystal characteristics are detailed in the section “DC
Characteristics”.
The X1 pin can also be used as input for an external 48 MHz clock.
The clock controller outputs three different clocks as shown in Figure 5-1:
• a clock for the CPU core
• a clock for the peripherals which is used to generate the Timers, PCA, WD, and Port
sampling clocks
• a clock for the USB controller
These clocks are enabled or disabled depending on the power reduction mode as detailed in
Section “Power Management”, page 155.
Figure 5-1.Oscillator Block Diagram
5.2Oscillator
Two types of clock sources can be used for CPU:
• Crystal oscillator on X1 and X2 pins: Up to 32 MHz (Amplifier Bandwidth)
• External clock on X1 pin: Up to 48MHz
14
4337K–USB–04/08
5.3PLL
VSS
X1
X2
Q
C1
C2
PLLEN
PLLCON.1
N3:0
N divider
R divider
VCOUSB Clock
US B clk
OSC clkR1+()×
N1+
-----------------------------------------------=
PFLD
PLOCK
PLLCON.0
PLLF
CHP
Vref
Up
Down
R3:0
USB
CLOCK
USB Clock Symbol
5.3.1PLL Description
AT89C5130A/31A-M
In order to optimize the power consumption, the oscillator inverter is inactive when the PLL output is not selected for the USB device.
Figure 5-2.Crystal Connection
The AT89C5130A/31A-M PLL is used to generate internal high frequency clock (the USB Clock)
synchronized with an external low-frequency (the Peripheral Clock). The PLL clock is used to
generate the USB interface clock. Figure 5-3 shows the internal structure of the PLL.
The PFLD block is the Phase Frequency Comparator and Lock Detector. This block makes the
comparison between the reference clock coming from the N divider and the reverse clock coming from the R divider and generates some pulses on the Up or Down signal depending on the
edge position of the reverse clock. The PLLEN bit in PLLCON register is used to enable the
clock generation. When the PLL is locked, the bit PLOCK in PLLCON register (see Figure 5-3) is
set.
The CHP block is the Charge Pump that generates the voltage reference for the VCO by injecting or extracting charges from the external filter connected on PLLF pin (see Figure 5-4). Value
of the filter components are detailed in the Section “DC Characteristics”.
The VCO block is the Voltage Controlled Oscillator controlled by the voltage V
the charge pump. It generates a square wave signal: the PLL clock.
Figure 5-3.PLL Block Diagram and Symbol
produced by
REF
4337K–USB–04/08
15
AT89C5130A/31A-M
Figure 5-4.PLL Filter Connection
VSS
PLLF
R
C1
C2
VSS
PLL
Programming
Configure Dividers
N3:0 = xxxxb
R3:0 = xxxxb
Enable PLL
PLLEN = 1
PLL Locked?
LOCK = 1?
The typical values are: R = 100 Ω, C1 = 10 nf, C2 = 2.2 nF.
5.3.2PLL Programming
The PLL is programmed using the flow shown in Figure 5-5. As soon as clock generation is
enabled user must wait until the lock indicator is set to ensure the clock output is stable.
Figure 5-5.PLL Programming Flow
5.3.3Divider Values
To generate a 48 MHz clock using the PLL, the divider values have to be configured following
the oscillator frequency. The typical divider values are shown in
Table 5-1.Typical Divider Values
16
Table 5-1.
Oscillator FrequencyR+1N+1PLLDIV
3 MHz161F0h
6 MHz8170h
8 MHz6150h
12 MHz4130h
16 MHz3120h
18 MHz8372h
20 MHz125B4h
24 MHz2110h
4337K–USB–04/08
5.4Registers
AT89C5130A/31A-M
Oscillator FrequencyR+1N+1PLLDIV
32 MHz3221h
40 MHz1210B9h
Table 5-2.CKCON0 (S:8Fh)
Clock Control Register 0
76543210
TWIX2WDX2PCAX2SIX2T2X2T1X2T0X2X2
Bit Number
7TWIX2
6WDX2
5PCAX2
4SIX2
3T2X2
Bit
Mnemonic Description
TWI Clock
This control bit is validated when the CPU clock X2 is set. When X2 is low,
this bit has no effect.
Clear to select 6 clock periods per peripheral clock cycle.
Set to select 12 clock periods per peripheral clock cycle.
Watchdog Clock
This control bit is validated when the CPU clock X2 is set. When X2 is low,
this bit has no effect.
Clear to select 6 clock periods per peripheral clock cycle.
Set to select 12 clock periods per peripheral clock cycle.
Programmable Counter Array Clock
This control bit is validated when the CPU clock X2 is set. When X2 is low,
this bit has no effect.
Clear to select 6 clock periods per peripheral clock cycle.
Set to select 12 clock periods per peripheral clock cycle.
Enhanced UART Clock (Mode 0 and 2)
This control bit is validated when the CPU clock X2 is set. When X2 is low,
this bit has no effect.
Clear to select 6 clock periods per peripheral clock cycle.
Set to select 12 clock periods per peripheral clock cycle.
Timer2 Clock
This control bit is validated when the CPU clock X2 is set. When X2 is low,
this bit has no effect.
Clear to select 6 clock periods per peripheral clock cycle.
Set to select 12 clock periods per peripheral clock cycle.
4337K–USB–04/08
2T1X2
1T0X2
0X2
Timer1 Clock
This control bit is validated when the CPU clock X2 is set. When X2 is low,
this bit has no effect.
Clear to select 6 clock periods per peripheral clock cycle.
Set to select 12 clock periods per peripheral clock cycle.
Timer0 Clock
This control bit is validated when the CPU clock X2 is set. When X2 is low,
this bit has no effect.
Clear to select 6 clock periods per peripheral clock cycle.
Set to select 12 clock periods per peripheral clock cycle.
System Clock Control bit
Clear to select 12 clock periods per machine cycle (STD mode, F
F
/
2).
OSC
Set to select 6 clock periods per machine cycle (X2 mode, F
= F
CPU
PER =
CPU = FPER = FOSC
).
17
AT89C5130A/31A-M
Reset Value = 0000 0000b
Table 5-3.CKCON1 (S:AFh)
Clock Control Register 1
76543210
-------SPIX2
Bit Number
7-1-
0SPIX2
Bit
Mnemonic Description
Reset Value = 0000 0000b
Table 5-4.PLLCON (S:A3h)
PLL Control Register
76543210
-----EXT48PLLENPLOCK
Bit Number
7-3-
2EXT48
Bit
Mnemonic Description
Reserved
The value read from this bit is always 0. Do not set this bit.
SPI Clock
This control bit is validated when the CPU clock X2 is set. When X2 is low,
this bit has no effect.
Clear to select 6 clock periods per peripheral clock cycle.
Set to select 12 clock periods per peripheral clock cycle.
Reserved
The value read from this bit is always 0. Do not set this bit.
External 48 MHz Enable Bit
Set this bit to bypass the PLL and disable the crystal oscillator.
Clear this bit to select the PLL output as USB clock and to enable the crystal
oscillator.
Reset Value = 0000 0000b
Table 5-5.PLLDIV (S:A4h)
18
PLL Enable Bit
1PLLEN
0PLOCK
Set to enable the PLL.
Clear to disable the PLL.
PLL Lock Indicator
Set by hardware when PLL is locked.
Clear by hardware when PLL is unlocked.
PLL Divider Register
76543210
R3R2R1R0N3N2N1N0
4337K–USB–04/08
AT89C5130A/31A-M
Bit Number
7-4R3:0PLL R Divider Bits
3-0N3:0PLL N Divider Bits
Bit
Mnemonic Description
Reset Value = 0000 0000
4337K–USB–04/08
19
AT89C5130A/31A-M
6.SFR Mapping
The Special Function Registers (SFRs) of the AT89C5130A/31A-M fall into the following
categories:
The additional data pointer can be used to speed up code execution and reduce code size.
The dual DPTR structure is a way by which the chip will specify the address of an external data
memory location. There are two 16-bit DPTR registers that address the external memory, and a
single bit called DPS = AUXR1.0 (see Table 7-1) that allows the program code to switch
between them (see Figure 7-1).
Figure 7-1.Use of Dual Pointer
AT89C5130A/31A-M
Table 7-1.AUXR1 Register
AUXR1- Auxiliary Register 1(0A2h)
76543210
--ENBOOT-GF30-DPS
Bit
Number
7-
6-
5ENBOOT
4-
3GF3This bit is a general-purpose user flag.
20Always cleared.
1-
0DPS
Bit
MnemonicDescription
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Enable Boot Flash
Cleared to disable boot ROM.
Set to map the boot ROM between F800h - 0FFFFh.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Data Pointer Selection
Cleared to select DPTR0.
Set to select DPTR1.
4337K–USB–04/08
Reset Value = XX[BLJB
]X X0X0b
Not bit addressable
a. Bit 2 stuck at 0; this allows to use INC AUXR1 to toggle DPS without changing GF3.
27
AT89C5130A/31A-M
ASSEMBLY LANGUAGE
; Block move using dual data pointers
; Modifies DPTR0, DPTR1, A and PSW
; note: DPS exits opposite of entry state
; unless an extra INC AUXR1 is added
;
00A2 AUXR1 EQU 0A2H
;
0000 909000MOV DPTR,#SOURCE ; address of SOURCE
0003 05A2 INC AUXR1 ; switch data pointers
0005 90A000 MOV DPTR,#DEST ; address of DEST
0008 LOOP:
0008 05A2 INC AUXR1 ; switch data pointers
000A E0 MOVX A,@DPTR ; get a byte from SOURCE
000B A3 INC DPTR ; increment SOURCE address
000C 05A2 INC AUXR1 ; switch data pointers
000E F0 MOVX @DPTR,A ; write the byte to DEST
000F A3 INC DPTR ; increment DEST address
0010 70F6JNZ LOOP ; check for 0 terminator
0012 05A2 INC AUXR1 ; (optional) restore DPS
INC is a short (2 bytes) and fast (12 clocks) way to manipulate the DPS bit in the AUXR1 SFR.
However, note that the INC instruction does not directly force the DPS bit to a particular state,
but simply toggles it. In simple routines, such as the block move example, only the fact that DPS
is toggled in the proper sequence matters, not its actual value. In other words, the block move
routine works the same whether DPS is '0' or '1' on entry. Observe that without the last instruction (INC AUXR1), the routine will exit with DPS in the opposite state.
28
4337K–USB–04/08
8.Program/Code Memory
0000h
32 Kbytes
7FFFh
Flash
32 Kbytes
External Code
FFFFh
AT89C5131A
8000h
0000h
16 Kbytes
3FFFh
Flash
48 Kbytes
External Code
FFFFh
AT89C5130A
4000h
The AT89C5130A/31A-M implement 16/ 32 Kbytes of on-chip program/code memory. Figure 81 shows the split of internal and external program/code memory spaces depending on the
product.
The Flash memory increases EPROM and ROM functionality by in-circuit electrical erasure and
programming. Thanks to the internal charge pump, the high voltage needed for programming or
erasing Flash cells is generated on-chip using the standard V
ory can be progra m m ed u s i ng o n ly o n e vo l t a ge and a l l o ws I n- a p p l i cation Softwa r e
Programming commonly known as IAP. Hardware programming mode is also available using
specific programming tool.
Figure 8-1.Program/Code Memory Organization
AT89C5130A/31A-M
voltage. Thus, the Flash Mem-
DD
Note:If the program executes exclusively from on-chip code memory (not from external memory),
beware of executing code from the upper byte of on-chip memory (3FFFh/7FFFh) and thereby
disrupting I/O Ports 0 and 2 due to external prefetch. Fetching code constant from this location
does not affect Ports 0 and 2.
8.1External Code Memory Access
8.1.1Memory Interface
The external memory interface comprises the external bus (Port 0 and Port 2) as well as the bus
control signals (PSEN, and ALE).
Figure 8-2 shows the structure of the external address bus. P0 carries address A7:0 while P2
carries address A15:8. Data D7:0 is multiplexed with A7:0 on P0. Table 8-1 describes the external memory interface signals.
This section describes the bus cycles the AT89C5130A/31A-M executes to fetch code (see
Figure 8-3) in the external program/code memory.
External memory cycle takes 6 CPU clock periods. This is equivalent to 12 oscillator clock periods in standard mode or 6 oscillator clock periods in X2 mode. For further information on X2
mode (see the clock Section).
For simplicity, the accompanying figure depicts the bus cycle waveforms in idealized form and
do not provide precise timing information.
Signal
NameType Description
A15:8O
AD7:0I/O
ALEO
PSENO
Address Lines
Upper address lines for the external bus.
Address/Data Lines
Multiplexed lower address lines and data for the external memory.
Address Latch Enable
ALE signals indicates that valid address information are available on lines
AD7:0.
Program Store Enable Output
This signal is active low during external code fetch or external code read
(MOVC instruction).
Alternate
Function
P2.7:0
P0.7:0
-
-
Figure 8-3.External Code Fetch Waveforms
30
4337K–USB–04/08
8.2Flash Memory Architecture
7FFFh for
16/32 KB
Flash Memory
FM0
0000h
Hardware Security (1 Byte)
Column Latches (128 Bytes)
User Space
Extra Row (128 Bytes)
3 Kbytes
Flash Memory
FM1
Boot Space
FFFFh
F400h
FM1 mapped between FFFFh and
F400h when bit ENBOOT is set in
AUXR1 register
3FFFh for
AT89C5131A
for 32 KB
AT89C5130A
for 16 KB
AT89C5130A/31A-M features two on-chip Flash memories:
• Flash memory FM0:
containing 32 Kbytes of program memory (user space) organized into 128-byte pages,
• Flash memory FM1:
3 Kbytes for bootloader and Application Programming Interfaces (API).
The FM0 supports both parallel programming and Serial In-System Programming (ISP) whereas
FM1 supports only parallel programming by programmers. The ISP mode is detailed in the “InSystem Programming” section.
All Read/Write access operations on Flash memory by user application are managed by a set of
API described in the “In-System Programming” section.
Figure 8-4.Flash Memory Architecture
AT89C5130A/31A-M
8.2.1FM0 Memory Architecture
The Flash memory is made up of 4 blocks (see Figure 8-4):
1.The memory array (user space) 32 Kbytes
2.The Extra Row
3.The Hardware security bits
4.The column latch registers
8.2.1.1User Space
This space is composed of a 16/32 Kbytes Flash memory organized in 128/256 pages of 128
bytes. It contains the user’s application code.
8.2.1.2Extra Row (XRow)
This row is a part of FM0 and has a size of 128 bytes. The extra row contains information for
bootloader usage (see
8.2.1.3Hardware Security Space
The hardware security space is a part of FM0 and has a size of 1 byte.
The 4 MSB can be read/written by software. The 4 LSB can only be read by software and written
by hardware in parallel mode.
4337K–USB–04/08
9-3 “Software Registers” on page 41)
31
AT89C5130A/31A-M
8.2.1.4Column Latches
The column latches, also part of FM0, have a size of full page (128 bytes).
The column latches are the entrance buffers of the three previous memory locations (user array,
XRow and Hardware security byte).
8.3Overview of FM0 Operations
The CPU interfaces to the Flash memory through the FCON register and AUXR1 register.
These registers are used to:
• Map the memory spaces in the adressable space
• Launch the programming of the memory spaces
• Get the status of the Flash memory (busy/not busy)
• Select the Flash memory FM0/FM1.
8.3.1Mapping of the Memory Space
By default, the user space is accessed by MOVC instruction for read only. The column latches
space is made accessible by setting the FPS bit in FCON register. Writing is possible from
0000h to 3FFFH/7FFFh, address bits 6 to 0 are used to select an address within a page while
bits 14 to 7 are used to select the programming address of the page.
Setting this bit takes precedence on the EXTRAM bit in AUXR register.
The other memory spaces (user, extra row, hardware security) are made accessible in the code
segment by programming bits FMOD0 and FMOD1 in FCON register in accordance with
Table 8-2. A MOVC instruction is then used for reading these spaces.
Table 8-2.FM0 Blocks Select Bits
8.3.2Launching Programming
FPL3:0 bits in FCON register are used to secure the launch of programming. A specific
sequence must be written in these bits to unlock the write protection and to launch the programming. This sequence is 5 followed by A. Table 8-3 summarizes the memory spaces to program
according to FMOD1:0 bits.
FMOD1FMOD0FM0 Adressable Space
00User (0000h-FFFFh)
01Extra Row(FF80h-FFFFh)
10Hardware Security (0000h)
11reserved
32
4337K–USB–04/08
Table 8-3.Programming Spaces
5X00No action
User
AX00
5X01No action
Extra Row
AX01
AT89C5130A/31A-M
Write to FCON
OperationFPL3:0FPSFMOD1FMOD0
Write the column latches in user
space
Write the column latches in extra row
space
Security
Space
Reserved
The Flash memory enters a busy state as soon as programming is launched. In this state, the
memory is not available for fetching code. Thus to avoid any erratic execution during programming, the CPU enters Idle mode. Exit is automatically performed at the end of programming.
Note:Interrupts that may occur during programming time must be disabled to avoid any spurious exit of
the idle mode.
8.3.3Status of the Flash Memory
The bit FBUSY in FCON register is used to indicate the status of programming.
FBUSY is set when programming is in progress.
8.3.4Selecting FM0/FM1
The bit ENBOOT in AUXR1 register is used to choose between FM0 and FM1 mapped up to
F800h.
8.3.5Loading the Column Latches
Any number of data from 1 byte to 128 bytes can be loaded in the column latches. This provides
the capability to program the whole memory by byte, by page or by any number of bytes in a
page.
5X10No action
AX10Write the fuse bits space
5X11No action
AX11No action
4337K–USB–04/08
When programming is launched, an automatic erase of the locations loaded in the column
latches is first performed, then programming is effectively done. Thus, no page or block erase is
needed and only the loaded data are programmed in the corresponding page.
The following procedure is used to load the column latches and is summarized in Figure 8-5:
• Map the column latch space by setting FPS bit.
• Load the DPTR with the address to load.
• Load Accumulator register with the data to load.
• Execute the MOVX @DPTR, A instruction.
• If needed loop the three last instructions until the page is completely loaded.
33
AT89C5130A/31A-M
Figure 8-5.Column Latches Loading Procedure
Column Latches
Loading
Data Load
DPTR = Address
ACC = Data
Exec: MOVX @DPTR, A
Last Byte
to load?
Column Latches Mapping
FPS = 1
Data memory Mapping
FPS = 0
8.3.6Programming the Flash Spaces
8.3.6.1User
8.3.6.2Extra Row
The following procedure is used to program the User space and is summarized in Figure 8-6:
(1)
• Load data in the column latches from address 0000h to 7FFFh
.
• Disable the interrupts.
• Launch the programming by writing the data sequence 50h followed by A0h in FCON
register.
The end of the programming indicated by the FBUSY flag cleared.
• Enable the interrupts.
Note:1. The last page address used when loading the column latch is the one used to select the page
programming address.
The following procedure is used to program the Extra Row space and is summarized in Figure 86:
• Load data in the column latches from address FF80h to FFFFh.
• Disable the interrupts.
• Launch the programming by writing the data sequence 52h followed by A2h in FCON
register.
The end of the programming indicated by the FBUSY flag cleared.
• Enable the interrupts.
34
4337K–USB–04/08
AT89C5130A/31A-M
Flash Spaces
Programming
Disable IT
EA = 0
Launch Programming
FCON = 5xh
FCON = Axh
End Programming
Enable IT
EA = 1
Column Latches Loading
see Figure 8-5
FBusy
Cleared?
Erase Mode
FCON = 00h
Figure 8-6.Flash and Extra Row Programming Procedure
8.3.6.3Hardware Security
The following procedure is used to program the Hardware Security space and is summarized in
Figure 8-7:
• Set FPS and map Hardware byte (FCON = 0x0C)
• Disable the interrupts.
• Load DPTR at address 0000h.
• Load Accumulator register with the data to load.
• Execute the MOVX @DPTR, A instruction.
• Launch the programming by writing the data sequence 54h followed by A4h in FCON
register.
The end of the programming indicated by the FBusy flag cleared.
• Enable the interrupts.
4337K–USB–04/08
35
AT89C5130A/31A-M
Figure 8-7.Hardware Programming Procedure
Flash Spaces
Programming
Disable IT
EA = 0
Launch Programming
FCON = 54h
FCON = A4h
End Programming
Enable IT
EA = 1
FBusy
Cleared?
Erase Mode
FCON = 00h
Data Load
DPTR = 00h
ACC = Data
Exec: MOVX @DPTR, A
FCON = 0Ch
8.3.7Reading the Flash Spaces
8.3.7.1User
The following procedure is used to read the User space and is summarized in Figure 8-8:
• Map the User space by writing 00h in FCON register.
• Read one byte in Accumulator by executing MOVC A, @A+DPTR with A = 0 & DPTR =
0000h to FFFFh.
8.3.7.2Extra Row
The following procedure is used to read the Extra Row space and is summarized in Figure 8-8:
• Map the Extra Row space by writing 02h in FCON register.
• Read one byte in Accumulator by executing MOVC A, @A+DPTR with A = 0 & DPTR =
FF80h to FFFFh.
36
4337K–USB–04/08
8.3.7.3Hardware Security
Flash Spaces Reading
Flash Spaces Mapping
FCON = 00000xx0b
Data Read
DPTR = Address
ACC = 0
Exec: MOVC A, @A+DPTR
Erase Mode
FCON = 00h
The following procedure is used to read the Hardware Security space and is summarized in
Figure 8-8:
• Map the Hardware Security space by writing 04h in FCON register.
• Read the byte in Accumulator by executing MOVC A, @A+DPTR with A = 0 & DPTR =
0000h.
Figure 8-8.Reading Procedure
AT89C5130A/31A-M
8.4Registers
Table 8-4.FCON (S:D1h)
Flash Control Register
76543210
FPL3FPL2FPL1FPL0FPSFMOD1FMOD0FBUSY
Bit Number
7-4FPL3:0
3FPS
2-1FMOD1:0
0FBUSY
Bit
Mnemonic Description
Reset Value = 0000 0000b
Programming Launch Command Bits
Write 5Xh followed by AXh to launch the programming according to FMOD1:0.
(see Table 8-3.)
Flash Map Program Space
Set to map the column latch space in the data memory space.
Clear to re-map the data memory space.
Flash Mode
See Table 8-2 or Table 8-3.
Flash Busy
Set by hardware when programming is in progress.
Clear by hardware when programming is done.
Can not be cleared by software.
4337K–USB–04/08
37
AT89C5130A/31A-M
9.Flash EEPROM Memory
9.1General Description
The Flash memory increases EPROM functionality with in-circuit electrical erasure and programming. It contains 16/32 Kbytes of program memory organized in 128/256 pages of 128 bytes,
respectively. This memory is both parallel and serial In-System Programmable (ISP). ISP allows
devices to alter their own program memory in the actual end product under software control. A
default serial loader (bootloader) program allows ISP of the Flash.
The programming does not require 12V external programming voltage. The necessary high programming voltage is generated on-chip using the standard V
9.2Features
• Flash EEPROM internal program memory.
• Boot vector allows user-provided Flash loader code to reside anywhere in the Flash memory
space. This configuration provides flexibility to the user.
• Default loader in Boot EEPROM allows programming via the serial port without the need of a
user provided loader.
• Up to 64K bytes external program memory if the internal program memory is disabled (EA =
0).
• Programming and erase voltage with standard power supply.
• Read/Program/Erase:
• Byte-wise read (without wait state).
• Byte or page erase and programming (10 ms).
• Typical programming time (32 Kbytes) in 4.5 sec.
• Parallel programming with 87C51 compatible hardware interface to programmer.
• Programmable security for the code in the Flash.
The 16/32 Kbytes Flash is programmed by bytes or by pages of 128 bytes. It is not necessary to
erase a byte or a page before programming. The programming of a byte or a page includes a
self erase before programming.
There are three methods of programming the Flash memory:
1.The on-chip ISP bootloader may be invoked which will use low level routines to pro-
2.The Flash may be programmed or erased in the end-user application by calling low-
3.The Flash may be programmed using the parallel method.
The bootloader and the Application Programming Interface (API) routines are located in the
Flash Bootloader.
38
gram the pages. The interface used for serial downloading of Flash is the USB.
level routines through a common entry point in the Boot Flash.
4337K–USB–04/08
9.4Flash Registers and Memory Map
The AT89C5130A/31A-M Flash memory uses several registers:
• Hardware register can be accessed with a parallel programmer.Some bits of the hardware
register can be changed, also, by API (i.e. X2 and BLJB bits of Hardware security Byte) or
ISP.
• Software registers are in a special page of the Flash memory which can be accessed through
the API or with the parallel programming modes. This page, called “Extra Flash Memory”, is
not in the internal Flash program memory addressing space.
9.4.1Hardware Registers
The only hardware register of the AT89C5130A/31A-M is called Hardware Security Byte (HSB).
Table 9-1.Hardware Security Byte (HSB)
76543210
X2BLJBOSCON1OSCON0-LB2LB1LB0
AT89C5130A/31A-M
Bit
Number
7X2
6BLJB
5-4OSCON1-0
3-Reserved
2-0LB2-0
9.4.1.1Bootloader Jump Bit (BLJB)
One bit of the HSB, the BLJB bit, is used to force the boot address:
• When this bit is set the boot address is 0000h.
• When this bit is reset the boot address is F400h. By default, this bit is cleared and the ISP is
enabled.
Bit
Mnemonic Description
X2 Mode
Cleared to force X2 mode (6 clocks per instruction)
Set to force X1 mode, Standard Mode (Default).
Bootloader Jump Bit
Set this bit to start the user’s application on next reset at address 0000h.
Cleared this bit to start the bootloader at address F400h (default).
Oscillator Control Bits
These two bits are used to control the oscillator in order to reduce consumption.
OSCON1
1 1 The oscillator is configured to run from 0 to 32 MHz
1 0 The oscillator is configured to run from 0 to 16 MHz
0 1 The oscillator is configured to run from 0 to 8 MHz
0 0 This configuration shouldn’t be set
User Memory Lock Bits
See Table 9-2
OSCON0 Description
9.4.1.2Flash Memory Lock Bits
The three lock bits provide different levels of protection for the on-chip code and data, when programmed as shown in Table 9-2.
4337K–USB–04/08
39
AT89C5130A/31A-M
Table 9-2.Program Lock bits
Program Lock Bits
Protection DescriptionSecurity levelLB0LB1LB2
1UUUNo program lock features enabled.
MOVC instruction executed from external
2PUU
3XPU
4XXPSame as 3, also external execution is disabled.
Notes:1. U: unprogrammed or “one” level.
2. P: programmed or “zero” level.
3. X: don’t care
4. WARNING: Security level 2 and 3 should only be programmed after verification.
program memory is disabled from fetching code
bytes from any internal memory, EA
and latched on reset, and further parallel
programming of the Flash and of the EEPROM
(boot and Xdata) is disabled. ISP and software
programming with API are still allowed.
Same as 2, also verify through parallel
programming interface is disabled and serial
programming ISP is still allowed.
is sampled
These security bits protect the code access through the parallel programming interface. They
are set by default to level 4. The code access through the ISP is still possible and is controlled
by the “software security bits” which are stored in the extra Flash memory accessed by the ISP
firmware.
To load a new application with the parallel programmer, a chip erase must be done first. This will
set the HSB in its inactive state and will erase the Flash memory. The part reference can always
be read using Flash parallel programming modes.
9.4.1.3Default Values
The default value of the HSB provides parts ready to be programmed with ISP:
• BLJB: Cleared to force ISP operation.
• X2: Set to force X1 mode (Standard Mode)
• OSCON1-0: Set to start with 32 MHz oscillator configuration value.
• LB2-0: Security level four to protect the code from a parallel access with maximum security.
9.4.2Software Registers
Several registers are used, in factory and by parallel programmers, to make copies of hardware
registers contents. These values are used by Atmel ISP (see Section “In-System Programming
(ISP)”).
These registers are in the “Extra Flash Memory” part of the Flash memory. This block is also
called ”XAF” or eXtra Array Flash. They are accessed in the following ways:
• Commands issued by the parallel memory programmer.
• Commands issued by the ISP software.
• Calls of API issued by the application software.
Several software registers are described in Table 9-3.
40
4337K–USB–04/08
Table 9-3.Software Registers
AddressMnemonicDescriptionDefault value
01SBVSoftware Boot VectorFFh–
00BSBBoot Status Byte0FFh–
05SSBSoftware Security ByteFFh–
AT89C5130A/31A-M
30–
31–
60–
61–
Copy of the Manufacturer
Code
Copy of the Device ID #1:
Family Code
Copy of the Device ID #2:
Memories
Copy of the Device ID #3:
Name
58hAtmel
D7h
F7h
DFh
C51 X2, Electrically
Erasable
AT89C5130A/31A-M 32
Kbyte
AT89C5130A/31A-M 32
Kbyte, revision 0
After programming the part by ISP, the BSB must be cleared (00h) in order to allow the application to boot at 0000h.
The content of the Software Security Byte (SSB) is described in
Table 9-4and Table 9-5.
To assure code protection from a parallel access, the HSB must also be at the required level.
Table 9-4.Software Security Byte (SSB)
76543210
------LB1LB0
Bit
Number
7-
Bit
MnemonicDescription
Reserved
Do not clear this bit.
4337K–USB–04/08
6-
5-
4-
3-
2-
1-0LB1-0
Reserved
Do not clear this bit.
Reserved
Do not clear this bit.
Reserved
Do not clear this bit.
Reserved
Do not clear this bit.
Reserved
Do not clear this bit.
User Memory Lock Bits
See Table 9-5
The two lock bits provide different levels of protection for the on-chip code and data, when programmed as shown to Table 9-5.
41
AT89C5130A/31A-M
Table 9-5.Program Lock Bits of the SSB
0000h
Virgin
Default
Virgin
After ISP
After parallel
programming
After parallel
programming
After parallel
programming
ApplicationApplication
After ISP
or
Dedicated
ISP
Dedicated
ISP
7FFFh
AT89C5131A-M
Application
Virgin
or
Application
Virgin
or
Application
3FFFh AT89C5130A-M
Program Lock Bits
Security
LevelLB0LB1
1UUNo program lock features enabled.
2PUISP programming of the Flash is disabled.
3PPSame as 2, also verify through ISP programming interface is disabled.
Notes:1. U: unprogrammed or "one" level.
2. P: programmed or “zero” level.
3. WARNING: Security level 2 and 3 should only be programmed after Flash and code
verification.
9.5Flash Memory Status
AT89C5130A/31A-M parts are delivered with the ISP boot in the Flash memory. After ISP or parallel programming, the possible contents of the Flash memory are summarized in Figure 9-1:
Figure 9-1.Flash Memory Possible Contents
Protection Description
9.6Memory Organization
In the AT89C5130A/31A-M, the lowest 16/32K of the 64 Kbyte program memory address space
is filled by internal Flash.
When the EA is pin high, the processor fetches instructions from internal program Flash. Bus
expansion for accessing program memory from 16/32K upward is automatic since external
instruction fetches occur automatically when the program counter exceeds 3FFFh (16K) or
7FFFh (32K). If the EA
42
all storage is on chip, then byte location 3FFFh (16K) or 7FFFh (32K) should be left vacant to
prevent and undesired pre-fetch from external program memory address 4000h (16K) or 8000h
(32K).
pin is tied low, all program memory fetches are from external memory. If
4337K–USB–04/08
10. EEPROM Data Memory
10.1Description
The 1-Kbyte on-chip EEPROM memory block is located at addresses 0000h to 03FFh of the
ERAM memory space and is selected by setting control bits in the EECON register.
A read in the EEPROM memory is done with a MOVX instruction.
A physical write in the EEPROM memory is done in two steps: write data in the column latches
and transfer of all data latches into an EEPROM memory row (programming).
The number of data written on the page may vary from 1 to 128 bytes (the page size). When programming, only the data written in the column latch is programmed and a ninth bit is used to
obtain this feature. This provides the capability to program the whole memory by bytes, by page
or by a number of bytes in a page. Indeed, each ninth bit is set when the writing the corresponding byte in a row and all these ninth bits are reset after the writing of the complete EEPROM row.
10.2Write Data in the Column Latches
Data is written by byte to the column latches as for an external RAM memory. Out of the 11
address bits of the data pointer, the 4 MSBs are used for page selection (row) and 7 are used for
byte selection. Between two EEPROM programming sessions, all the addresses in the column
latches must stay on the same page, meaning that the 4 MSB must not be changed.
AT89C5130A/31A-M
10.3Programming
10.4Read Data
The following procedure is used to write to the column latches:
• Set bit EEE of EECON register
• Load DPTR with the address to write
• Store A register with the data to be written
• Execute a MOVX @DPTR, A
• If needed, loop the three last instructions until the end of a 128 bytes page
The EEPROM programming consists on the following actions:
• Writing one or more bytes of one page in the column latches. Normally, all bytes must belong
to the same page; if not, the first page address will be latched and the others discarded.
• Launching programming by writing the control sequence (52h followed by A2h) to the
EECON register.
• EEBUSY flag in EECON is then set by hardware to indicate that programming is in progress
and that the EEPROM segment is not available for reading.
• The end of programming is indicated by a hardware clear of the EEBUSY flag.
The following procedure is used to read the data stored in the EEPROM memory:
4337K–USB–04/08
• Set bit EEE of EECON register
• Stretch the MOVX to accommodate the slow access time of the column latch (Set bit M0 of
AUXR register)
• Load DPTR with the address to read
• Execute a MOVX A, @DPTR
43
AT89C5130A/31A-M
10.5Registers
Table 10-1.EECON (S:0D2h)
EECON Register
76543210
EEPL3EEPL2EEPL1EEPL0--EEEEEBUSY
Bit Number
7-4EEPL3-0
3-
2-
1EEE
0EEBUSY
Bit
Mnemonic Description
Reset Value = XXXX XX00b
Not bit addressable
Programming Launch command bits
Write 5Xh followed by AXh to EEPL to launch the programming.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Enable EEPROM Space bit
Set to map the EEPROM space during MOVX instructions (Write in the column
latches)
Clear to map the ERAM space during MOVX.
Programming Busy flag
Set by hardware when programming is in progress.
Cleared by hardware when programming is done.
Cannot be set or cleared by software.
44
4337K–USB–04/08
11. In-System Programming (ISP)
With the implementation of the User Space (FM0) and the Boot Space (FM1) in Flash technology the AT89C5130A/31A-M allows the system engineer the development of applications with a
very high level of flexibility. This flexibility is based on the possibility to alter the customer program at any stages of a product’s life:
AT89C5130A/31A-M
• Before mounting the chip on the PCB, FM0 flash can be programmed with the application
code. FM1 is always preprogrammed by Atmel with a USB bootloader.
• Once the chip is mounted on the PCB, it can be programmed by serial mode via the USB
bus.
Note:1. The user can also program his own bootloader in FM1.
This ISP allows code modification over the total lifetime of the product.
Besides the default Bootloaders Atmel provide customers all the needed Application-Programming-Interfaces (API) which are needed for the ISP. The API are located in the Boot memory.
This allow the customer to have a full use of the 32-Kbyte user memory.
11.1Flash Programming and Erasure
There are three methods for programming the Flash memory:
• The Atmel bootloader located in FM1 is activated by the application. Low level API routines
(located in FM1)will be used to program FM0. The interface used for serial downloading to
FM0 is the USB. API can be called also by user’s bootloader located in FM0 at [SBV]00h.
• A further method exist in activating the Atmel boot loader by hardware activation. See the
Section “Hardware Registers”.
• The FM0 can be programmed also by the parallel mode using a programmer.
(1)
4337K–USB–04/08
45
AT89C5130A/31A-M
Figure 11-1. Flash Memory Mapping
F400h
7FFFh
32K Bytes
Flash Memory
3K Bytes IAP
Bootloader
FM0
FM1
Custom
Bootloader
[SBV]00h
FFFFh
FM1 Mapped between F400h and FFFFh
when API Called
0000h
3FFFh
16K Bytes
Flash Memory
FM0
Custom
Bootloader
[SBV]00h
0000h
C5130AC5131A
11.2Boot Process
11.2.1Software Boot Process Example
Many algorithms can be used for the software boot process. Below are descriptions of the different flags and Bytes.
Boot Loader Jump bit (BLJB):
- This bit indicates if on RESET the user wants to jump to this application at address @0000h on
FM0 or execute the boot loader at address @F400h on FM1.
- BLJB = 0 (i.e. bootloader FM1 executed after a reset) is the default Atmel factory programming.
-To read or modify this bit, the APIs are used.
Boot Vector Address (SBV):
- This byte contains the MSB of the user boot loader address in FM0.
- The default value of SBV is FFh (no user boot loader in FM0).
- To read or modify this byte, the APIs are used.
Extra Byte (EB) & Boot Status Byte (BSB):
- These Bytes are reserved for customer use.
- To read or modify these Bytes, the APIs are used.
46
4337K–USB–04/08
Figure 11-2. Hardware Boot Process Algorithm
RESET
BLJB == 0
?
Hardware
Software
Bootloader
in FM1
Application
in FM0
bit ENBOOT in AUXR1 Register
Is Initialized with BLJB Inverted.
ENBOOT = 0
PC = 0000h
ENBOOT = 1
PC = F400h
Example, if BLJB=0, ENBOOT
is set (=1) during reset, thus the
bootloader is executed after the
reset.
AT89C5130A/31A-M
11.3Application-Programming-Interface
Several Application Program Interface (API) calls are available for use by an application program to permit selective erasing and programming of Flash pages. All calls are made by
functions.
All these APIs are described in detail in the following document on the Atmel web site.
– Datasheet Bootloader USB AT89C5131.
11.4XROW Bytes
The EXTRA ROW (XROW) includes 128 bytes. Some of these bytes are used for specific purpose in conjonction with the bootloader.
Table 11-1.XROW Mapping
DescriptionDefault ValueAddress
Copy of the Manufacturer Code58h30h
Copy of the Device ID#1: Family codeD7h31h
Copy of the Device ID#2: Memories size and typeBBh60h
4337K–USB–04/08
47
AT89C5130A/31A-M
DescriptionDefault ValueAddress
ALE
EA
VCC
/PSEN
RST
GND
1K
Unconnected
VCC
VSS
VCC
GND
GND
C1
C2
Crystal
GND
XTAL2
XTAL1
Bootloader
GND
Copy of the Device ID#3: Name and RevisionFFh61h
11.5Hardware Conditions
It is possible to force the controller to execute the bootloader after a Reset with hardware conditions. Depending on the product type (low pin count or high pin count package), there are two
methods to apply the hardware conditions.
For high pin count packages, the hardware conditons (EA = 1, PSEN = 0) are sampled during
the RESET
172). In this way the bootloader can be carried out regardless of the user Flash memory content.
It is recommended to pull the PSEN pin down to ground though a 1K resistor to prevent the
PSEN pin from being damaged (see Figure 11-3 below).
Figure 11-3. ISP Hardware conditions
rising edge to force the on-chip bootloader execution (See Figure 27-5 on page
As PSEN is an output port in normal operating mode (running user application or bootloader
code) after reset, it is recommended to release PSEN after rising edge of reset signal.
To ensure correct microcontroller startup, the PSEN pin should not be tied to ground during
power-on (see
48
Figure 11-4 below).
4337K–USB–04/08
Figure 11-4. Hardware conditions typical sequence during power-on.
VCC
PSEN
RST
11.5.2Low Pin Count Hardware Conditions (QFN32)
Low pin count products do not have PSEN signal, thus for these products, the bootloader is
always executed after reset thanks to the BLJB bit. The Hardware Condition are detected at the
begining of the bootloader execution from reset.
The default factory Hardware Condition is assigned to port P1.
AT89C5130A/31A-M
• P1 must be equal to FEh
In order to offer the best flexibility, the user can define its own Hardware Condition on one of the
following Ports:
• Port1
• Port3
• Port4 (only bit0 and bit1)
The Hardware Condition configuration are stored in three bytes called P1_CF, P3_CF, P4_CF.
These bytes can be modified by the user through a set of API or through an ISP command.
Note:1. The BLJB must be at 0 (programmed) to be able to restart the bootloader.
2. BLJB can always be changed by the means of API, whether it's a low or high pin count package.But for a low pin count version, if BLJB=1, no ISP via the Bootloader is further possible
(because the HW conditions are never evaluated, as described in the USB Bootloader
Datasheet). To go back to ISP, BLJB needs to be changed by a parallel programmer(or by the
APIs).
See a detailed description in the applicable Document.
– Datasheet Bootloader USB AT89C5131.
4337K–USB–04/08
49
AT89C5130A/31A-M
12. On-chip Expanded RAM (ERAM)
ERAM
Upper
128 bytes
Internal
RAM
Lower
128 bytes
Internal
RAM
Special
Function
Register
80h80h
00
0FFh or 3FFh(*)
0FFh
00
0FFh
External
Data
Memory
0000
00FFh up to 03FFh (*)
0FFFFh
indirect accesses
direct accesses
direct or indirect
accesses
7Fh
(*) Depends on XRS1..0
The AT89C5130A/31A-M provides additional Bytes of random access memory (RAM) space for
increased data parameters handling and high level language usage.
AT89C5130A/31A-M devices have expanded RAM in external data space; maximum size and
location are described in Table 12-1.
Table 12-1.Description of Expanded RAM
Address
Part NumberERAM Size
AT89C5130A/31A-M102400h3FFh
The AT89C5130A/31A-M has on-chip data memory which is mapped into the following four separate segments.
1.The Lower 128 bytes of RAM (addresses 00h to 7Fh) are directly and indirectly
addressable.
2.The Upper 128 bytes of RAM (addresses 80h to FFh) are indirectly addressable only.
3.The Special Function Registers, SFRs, (addresses 80h to FFh) are directly addressable only.
4.The expanded RAM bytes are indirectly accessed by MOVX instructions, and with the
EXTRAM bit cleared in the AUXR register (see Table 12-1)
The lower 128 bytes can be accessed by either direct or indirect addressing. The Upper 128
bytes can be accessed by indirect addressing only. The Upper 128 bytes occupy the same
address space as the SFR. That means they have the same address, but are physically separate from SFR space.
Figure 12-1. Internal and External Data Memory Address
StartEnd
When an instruction accesses an internal location above address 7Fh, the CPU knows whether
the access is to the upper 128 bytes of data RAM or to SFR space by the addressing mode used
in the instruction.
50
4337K–USB–04/08
AT89C5130A/31A-M
• Instructions that use direct addressing access SFR space. For example: MOV 0A0H, # data,
accesses the SFR at location 0A0h (which is P2).
• Instructions that use indirect addressing access the Upper 128 bytes of data RAM. For
example: MOV atR0, # data where R0 contains 0A0h, accesses the data byte at address
0A0h, rather than P2 (whose address is 0A0h).
• The ERAM bytes can be accessed by indirect addressing, with EXTRAM bit cleared and
MOVX instructions. This part of memory which is physically located on-chip, logically
occupies the first bytes of external data memory. The bits XRS0 and XRS1 are used to hide a
part of the available ERAM as explained in Table 12-1. This can be useful if external
peripherals are mapped at addresses already used by the internal ERAM.
• With EXTRAM = 0,
combination with any of the registers R0, R1 of the selected bank or DPTR. An access to
ERAM will not affect ports P0, P2, P3.6 (WR) and P3.7 (RD). For example, with EXTRAM =
0, MOVX atR0, # data where R0 contains 0A0H, accesses the ERAM at address 0A0H rather
than external memory. An access to external data memory locations higher than the
accessible size of the ERAM will be performed with the MOVX DPTR instructions in the same
way as in the standard 80C51, with P0 and P2 as data/address busses, and P3.6 and P3.7
as write and read timing signals. Accesses to ERAM above 0FFH can only be done by the
use of DPTR.
• With EXTRAM = 1, MOVX @Ri and MOVX @DPTR will be similar to the standard 80C51.
MOVX at Ri will provide an eight-bit address multiplexed with data on Port0 and any output
port pins can be used to output higher order address bits. This is to provide the external
paging capability. MOVX @DPTR will generate a sixteen-bit address. Port2 outputs the highorder eight address bits (the contents of DPH) while Port0 multiplexes the low-order eight
address bits (DPL) with data. MOVX at Ri and MOVX @DPTR will generate either read or
write signals on P3.6 (WR) and P3.7 (RD).
The stack pointer (SP) may be located anywhere in the 256 bytes RAM (lower and upper RAM)
internal data memory. The stack may not be located in the ERAM.
the ERAM is indirectly addressed, using the MOVX instruction in
4337K–USB–04/08
The M0 bit allows to stretch the ERAM timings; if M0 is set, the read and write pulses are
extended from 6 to 30 clock periods. This is useful to access external slow peripherals.
Table 12-2.AUXR Register
AUXR - Auxiliary Register (8Eh)
76543210
DPU-M0-XRS1XRS0EXTRAMAO
Bit
Number
7DPU
6-
Bit
MnemonicDescription
Disable Weak Pull Up
Cleared to enabled weak pull up on standard Ports.
Set to disable weak pull up on standard Ports.
Reserved
The value read from this bit is indeterminate. Do not set this bit
51
AT89C5130A/31A-M
Bit
Number
5M0
Bit
MnemonicDescription
Pulse length
Cleared to stretch MOVX control: the RD and the WR pulse length is 6 clock
periods (default).
Set to stretch MOVX control: the RD and the WR pulse length is 30 clock
periods.
4-
3XRS1ERAM Size
2XRS0
1EXTRAM
0AO
Reset Value = 0X0X 1100b
Not bit addressable
Reserved
The value read from this bit is indeterminate. Do not set this bit
XRS1XRS0ERAM size
00256 bytes
01512 bytes
10768 bytes
111024 bytes (default)
EXTRAM bit
Cleared to access internal ERAM using MOVX at Ri at DPTR.
Set to access external memory.
ALE Output bit
Cleared, ALE is emitted at a constant rate of 1/6 the oscillator frequency (or
1/3 if X2 mode is used) (default).
Set, ALE is active only when a MOVX or MOVC instruction is used.
52
4337K–USB–04/08
13. Timer 2
The Timer 2 in the AT89C5130A/31A-M is the standard C52 Timer 2. It is a 16-bit timer/counter:
the count is maintained by two cascaded eight-bit timer registers, TH2 and TL2. It is controlled
by T2CON (Table 13-1) and T2MOD (Table 13-2) registers. Timer 2 operation is similar to Timer
0 and Timer 1. C/T2 selects F
the timer clock input. Setting TR2 allows TL2 to be incremented by the selected input.
Timer 2 has 3 operating modes: capture, auto reload and Baud Rate Generator. These modes
are selected by the combination of RCLK, TCLK and CP/RL2
Refer to the Atmel 8-bit microcontroller hardware documentation for the description of Capture
and Baud Rate Generator Modes.
Timer 2 includes the following enhancements:
• Auto-reload mode with up or down counter
• Programmable Clock-output
13.1Auto-reload Mode
The Auto-reload mode configures Timer 2 as a 16-bit timer or event counter with automatic
reload. If DCEN bit in T2MOD is cleared, Timer 2 behaves as in 80C52 (refer to the Atmel 8-bit
microcontroller har dware description). If DCE N bit is set, Timer 2 acts a s an Up/down
timer/counter as shown in Figure 13-1. In this mode the T2EX pin controls the direction of count.
AT89C5130A/31A-M
/12 (timer operation) or external pin T2 (counter operation) as
OSC
(T2CON).
When T2EX is high, Timer 2 counts up. Timer overflow occurs at FFFFh which sets the TF2 flag
and generates an interrupt request. The overflow also causes the 16-bit value in RCAP2H and
RCAP2L registers to be loaded into the timer registers TH2 and TL2.
When T2EX is low, Timer 2 counts down. Timer underflow occurs when the count in the timer
registers TH2 and TL2 equals the value stored in RCAP2H and RCAP2L registers. The underflow sets TF2 flag and reloads FFFFh into the timer registers.
The EXF2 bit toggles when Timer 2 overflows or underflows according to the direction of the
count. EXF2 does not generate any interrupt. This bit can be used to provide 17-bit resolution.
In the Clock-out mode, Timer 2 operates as a 50%-duty-cycle, programmable clock generator
(See Figure 13-2). The input clock increments TL2 at frequency F
edly counts to overflow from a loaded value. At overflow, the contents of RCAP2H and RCAP2L
registers are loaded into TH2 and TL2. In this mode, Timer 2 overflows do not generate interrupts. The following formula gives the Clock-out frequency as a function of the system oscillator
frequency and the value in the RCAP2H and RCAP2L registers
For a 16 MHz system clock, Timer 2 has a programmable frequency range of 61 Hz
(F
CLK PERIPH
(P1.0).
Timer 2 is programmed for the Clock-out mode as follows:
• Set T2OE bit in T2MOD register.
• Clear C/T2 bit in T2CON register.
• Determine the 16-bit reload value from the formula and enter it in RCAP2H/RCAP2L
registers.
• Enter a 16-bit initial value in timer registers TH2/TL2. It can be the same as the reload value
or a different one depending on the application.
• To start the timer, set TR2 run control bit in T2CON register.
16)
/2
to 4 MHz (F
CLK PERIPH
CLK PERIPH
/2. The timer repeat-
/4). The generated clock signal is brought out to T2 pin
54
4337K–USB–04/08
AT89C5130A/31A-M
EXF2
TR2
OVERFLOW
T2EX
TH2
(8-bit)
TL2
(8-bit)
Timer 2
RCAP2H
(8-bit)
RCAP2L
(8-bit)
T2OE
T2
F
CLK PERIPH
T2CON
T2CON
T2CON
T2MOD
INTERRUPT
QD
Toggle
EXEN2
It is possible to use Timer 2 as a baud rate generator and a clock generator simultaneously. For
this configuration, the baud rates and clock frequencies are not independent since both functions use the values in the RCAP2H and RCAP2L registers.
Figure 13-2. Clock-out Mode C/T2 = 0
4337K–USB–04/08
55
AT89C5130A/31A-M
Table 13-1.T2CON Register
T2CON - Timer 2 Control Register (C8h)
76543210
TF2EXF2RCLKTCLKEXEN2TR2C/T2#CP/RL2#
Bit
Number
7TF2
6EXF2
5RCLK
4TCLK
3EXEN2
2TR2
Bit
MnemonicDescription
Timer 2 overflow Flag
Must be cleared by software.
Set by hardware on Timer 2 overflow, if RCLK = 0 and TCLK = 0.
Timer 2 External Flag
Set when a capture or a reload is caused by a negative transition on T2EX pin if
EXEN2 = 1.
When set, causes the CPU to vector to Timer 2 interrupt routine when Timer 2 interrupt
is enabled.
Must be cleared by software. EXF2 doesn’t cause an interrupt in Up/down counter
mode (DCEN = 1).
Receive Clock bit
Cleared to use Timer 1 overflow as receive clock for serial port in mode 1 or 3.
Set to use Timer 2 overflow as receive clock for serial port in mode 1 or 3.
Transmit Clock bit
Cleared to use Timer 1 overflow as transmit clock for serial port in mode 1 or 3.
Set to use Timer 2 overflow as transmit clock for serial port in mode 1 or 3.
Timer 2 External Enable bit
Cleared to ignore events on T2EX pin for Timer 2 operation.
Set to cause a capture or reload when a negative transition on T2EX pin is detected, if
Timer 2 is not used to clock the serial port.
Timer 2 Run control bit
Cleared to turn off Timer 2.
Set to turn on Timer 2.
56
1C/T2#
0CP/RL2#
Reset Value = 0000 0000b
Bit addressable
Timer/Counter 2 select bit
Cleared for timer operation (input from internal clock system: F
Set for counter operation (input from T2 input pin, falling edge trigger). Must be 0 for
clock out mode.
Timer 2 Capture/Reload bit
If RCLK = 1 or TCLK = 1, CP/RL2# is ignored and timer is forced to Auto-reload on
Timer 2 overflow.
Cleared to Auto-reload on Timer 2 overflows or negative transitions on T2EX pin if
EXEN2 = 1.
Set to capture on negative transitions on T2EX pin if EXEN2 = 1.
CLK PERIPH
).
4337K–USB–04/08
AT89C5130A/31A-M
Table 13-2.T2MOD Register
T2MOD - Timer 2 Mode Control Register (C9h)
76543210
------T2OEDCEN
Bit
Number
7-
6-
5-
4-
3-
2-
1T2OE
0DCEN
Bit
MnemonicDescription
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Timer 2 Output Enable bit
Cleared to program P1.0/T2 as clock input or I/O port.
Set to program P1.0/T2 as clock output.
Down Counter Enable bit
Cleared to disable Timer 2 as up/down counter.
Set to enable Timer 2 as up/down counter.
Reset Value = XXXX XX00b
Not bit addressable
4337K–USB–04/08
57
AT89C5130A/31A-M
14. Programmable Counter Array (PCA)
The PCA provides more timing capabilities with less CPU intervention than the standard
timer/counters. Its advantages include reduced software overhead and improved accuracy. The
PCA consists of a dedicated timer/counter which serves as the time base for an array of five
compare/capture modules. Its clock input can be programmed to count any one of the following
signals:
• Peripheral clock frequency (F
• Peripheral clock frequency (F
CLK PERIPH
CLK PERIPH
) ÷ 6
) ÷ 2
• Timer 0 overflow
• External input on ECI (P1.2)
Each compare/capture modules can be programmed in any one of the following modes:
• rising and/or falling edge capture,
• software timer
• high-speed output, or
• pulse width modulator
Module 4 can also be programmed as a watchdog timer (see Section "PCA Watchdog Timer",
page 68).
When the compare/capture modules are programmed in the capture mode, software timer, or
high speed output mode, an interrupt can be generated when the module executes its function.
All five modules plus the PCA timer overflow share one interrupt vector.
The PCA timer/counter and compare/capture modules share Port 1 for external I/O. These pins
are listed below. If the port pin is not used for the PCA, it can still be used for standard I/O.
PCA ComponentExternal I/O Pin
16-bit CounterP1.2/ECI
58
16-bit Module 0P1.3/CEX0
16-bit Module 1P1.4/CEX1
16-bit Module 2P1.5/CEX2
16-bit Module 3P1.6/CEX3
16-bit Module 4P1.7/CEX4
The PCA timer is a common time base for all five modules (see Figure 14-1). The timer count
source is determined from the CPS1 and CPS0 bits in the CMOD register (Table 14-1) and can
be programmed to run at:
• 1/6 the
peripheral clock frequency (F
• 1/2 the peripheral clock frequency (F
CLK PERIPH
CLK PERIPH
).
).
• The Timer 0 overflow
• The input on the ECI pin (P1.2)
4337K–USB–04/08
Figure 14-1. PCA Timer/Counter
CIDLCPS1 CPS0ECF
It
CHCL
16 Bit Up Counter
To PCA
modules
F
CLK PERIPH
/6
F
CLK PERIPH
/2
T0 OVF
P1.2
Idle
CMOD
0xD9
WDTE
CFCR
CCON
0xD8
CCF4 CCF3 CCF2 CCF1 CCF0
overflow
AT89C5130A/31A-M
Table 14-1.CMOD Register
CMOD - PCA Counter Mode Register (D9h)
76543210
CIDLWDTE---CPS1CPS0ECF
Bit
Number
7CIDL
6WDTE
5-
4-
3-
2CPS1PCA Count Pulse Select
1CPS0
0ECF
Bit
MnemonicDescription
Counter Idle Control
Cleared to program the PCA Counter to continue functioning during idle Mode.
Set to program PCA to be gated off during idle.
Watchdog Timer Enable
Cleared to disable Watchdog Timer function on PCA Module 4.
Set to enable Watchdog Timer function on PCA Module 4.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
CPS1CPS0Selected PCA input
00Internal clock f
01Internal clock f
10Timer 0 Overflow
11External clock at ECI/P1.2 pin (max rate = f
PCA Enable Counter Overflow Interrupt
Cleared to disable CF bit in CCON to inhibit an interrupt.
Set to enable CF bit in CCON to generate an interrupt.
CLK PERIPH
CLK PERIPH
/6
/2
CLK PERIPH
/ 4)
4337K–USB–04/08
59
AT89C5130A/31A-M
Reset Value = 00XX X000b
Not bit addressable
The CMOD register includes three additional bits associated with the PCA (See Figure 14-1 and
Table 14-1).
• The CIDL bit allows the PCA to stop during idle mode.
• The WDTE bit enables or disables the watchdog function on module 4.
• The ECF bit when set causes an interrupt and the PCA overflow flag CF (in the CCON SFR)
to be set when the PCA timer overflows.
The CCON register contains the run control bit for the PCA and the flags for the PCA timer (CF)
and each module (see Table 14-2).
• Bit CR (CCON.6) must be set by software to run the PCA. The PCA is shut off by clearing this
bit.
• Bit CF: The CF bit (CCON.7) is set when the PCA counter overflows and an interrupt will be
generated if the ECF bit in the CMOD register is set. The CF bit can only be cleared by
software.
• Bits 0 through 4 are the flags for the modules (bit 0 for module 0, bit 1 for module 1, etc.) and
are set by hardware when either a match or a capture occurs. These flags can only be
cleared by software.
Table 14-2.CCON Register
CCON - PCA Counter Control Register (D8h)
76543210
CFCR–CCF4CCF3CCF2CCF1CCF0
Bit
Number
7CF
6CR
5–
4CCF4
3CCF3
2CCF2
Bit
Mnemonic Description
PCA Counter Overflow flag
Set by hardware when the counter rolls over. CF flags an interrupt if bit ECF in CMOD is set.
CF may be set by either hardware or software but can only be cleared by software.
PCA Counter Run control bit
Must be cleared by software to turn the PCA counter off.
Set by software to turn the PCA counter on.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
PCA Module 4 interrupt flag
Must be cleared by software.
Set by hardware when a match or capture occurs.
PCA Module 3 interrupt flag
Must be cleared by software.
Set by hardware when a match or capture occurs.
PCA Module 2 interrupt flag
Must be cleared by software.
Set by hardware when a match or capture occurs.
60
4337K–USB–04/08
AT89C5130A/31A-M
CFCR
CCON
0xD8
CCF4 CCF3 CCF2 CCF1 CCF0
Module 4
Module 3
Module 2
Module 1
Module 0
ECF
PCA Timer/Counter
ECCFn
CCAPMn.0CMOD.0
IE.6IE.7
To Interrupt
priority decoder
ECEA
Bit
Number
1CCF1
0CCF0
Reset Value = 000X 0000b
Not bit addressable
The watchdog timer function is implemented in module 4 (See Figure 14-4).
The PCA interrupt system is shown in Figure 14-2.
Figure 14-2. PCA Interrupt System
Bit
Mnemonic Description
PCA Module 1 Interrupt Flag
Must be cleared by software.
Set by hardware when a match or capture occurs.
PCA Module 0 Interrupt Flag
Must be cleared by software.
Set by hardware when a match or capture occurs.
4337K–USB–04/08
PCA Modules: each one of the five compare/capture modules has six possible functions. It can
perform:
• 16-bit capture, positive-edge triggered
• 16-bit capture, negative-edge triggered
• 16-bit capture, both positive and negative-edge triggered
• 16-bit Software Timer
• 16-bit High-speed Output
• 8-bit Pulse Width Modulator
In addition, module 4 can be used as a Watchdog Timer.
Each module in the PCA has a special function register associated with it. These registers are:
CCAPM0 for module 0, CCAPM1 for module 1, etc. (see Table 14-3). The registers contain the
bits that control the mode that each module will operate in.
61
AT89C5130A/31A-M
• The ECCF bit (CCAPMn.0 where n = 0, 1, 2, 3, or 4 depending on the module) enables the
CCF flag in the CCON SFR to generate an interrupt when a match or compare occurs in the
associated module.
• PWM (CCAPMn.1) enables the pulse width modulation mode.
• The TOG bit (CCAPMn.2) when set causes the CEX output associated with the module to
toggle when there is a match between the PCA counter and the module's capture/compare
register.
• The match bit MAT (CCAPMn.3) when set will cause the CCFn bit in the CCON register to be
set when there is a match between the PCA counter and the module's capture/compare
register.
• The next two bits CAPN (CCAPMn.4) and CAPP (CCAPMn.5) determine the edge that a
capture input will be active on. The CAPN bit enables the negative edge, and the CAPP bit
enables the positive edge. If both bits are set both edges will be enabled and a capture will
occur for either transition.
• The last bit in the register ECOM (CCAPMn.6) when set enables the comparator function.
Table 14-4 shows the CCAPMn settings for the various PCA functions.
CCAPM1 - PCA Module 1 Compare/Capture Control Register (0DBh)
CCAPM2 - PCA Module 2 Compare/Capture Control Register (0DCh)
CCAPM3 - PCA Module 3 Compare/Capture Control Register (0DDh)
CCAPM4 - PCA Module 4 Compare/Capture Control Register (0DEh)
76543210
-ECOMnCAPPnCAPNnMATnTOGnPWMnECCFn
Bit
Number
7-
6ECOMn
5CAPPn
4CAPNn
3MATn
2TOGn
Bit
MnemonicDescription
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Enable Comparator
Cleared to disable the comparator function.
Set to enable the comparator function.
Capture Positive
Cleared to disable positive edge capture.
Set to enable positive edge capture.
Capture Negative
Cleared to disable negative edge capture.
Set to enable negative edge capture.
Match
When MATn = 1, a match of the PCA counter with this module's compare/capture
register causes the
CCFn bit in CCON to be set, flagging an interrupt.
Toggle
When TOGn = 1, a match of the PCA counter with this module's compare/capture
register causes the CEXn pin to toggle.
62
4337K–USB–04/08
AT89C5130A/31A-M
Bit
Number
1PWMn
0ECCFn
Bit
MnemonicDescription
Pulse Width Modulation Mode
Cleared to disable the CEXn pin to be used as a pulse width modulated output.
Set to enable the CEXn pin to be used as a pulse width modulated output.
Enable CCF Interrupt
Cleared to disable compare/capture flag CCFn in the CCON register to generate an
interrupt.
Set to enable compare/capture flag CCFn in the CCON register to generate an
interrupt.
Reset Value = X000 0000b
Not bit addressable
Table 14-4.PCA Module Modes (CCAPMn Registers)
ECOMnCAPPnCAPNnMATnTOGnPWMm ECCFn Module Function
0000000 No Operation
X10000X
X01000X
X11000X
16-bit capture by a positive-edge
trigger on CEXn
16-bit capture by a negative trigger
on CEXn
16-bit capture by a transition on
CEXn
100100X
100110X16-bit High Speed Output
10000108-bit PWM
1001X0XWatchdog Timer (module 4 only)
16-bit Software Timer/Compare
mode.
There are two additional registers associated with each of the PCA modules. They are CCAPnH
and CCAPnL and these are the registers that store the 16-bit count when a capture occurs or a
compare should occur. When a module is used in the PWM mode these registers are used to
control the duty cycle of the output (see Table 14-5 and Table 14-6)
Table 14-5.CCAPnH Registers (n = 0-4)
CCAP0H - PCA Module 0 Compare/Capture Control Register High (0FAh)
CCAP1H - PCA Module 1 Compare/Capture Control Register High (0FBh)
CCAP2H - PCA Module 2 Compare/Capture Control Register High (0FCh)
CCAP3H - PCA Module 3 Compare/Capture Control Register High (0FDh)
CCAP4H - PCA Module 4 Compare/Capture Control Register High (0FEh)
To use one of the PCA modules in the capture mode either one or both of the CCAPM bits
CAPN and CAPP for that module must be set. The external CEX input for the module (on port 1)
is sampled for a transition. When a valid transition occurs the PCA hardware loads the value of
the PCA counter registers (CH and CL) into the module's capture registers (CCAPnL and
CCAPnH). If the CCFn bit for the module in the CCON SFR and the ECCFn bit in the CCAPMn
SFR are set then an interrupt will be generated (see Figure 14-3).
Figure 14-3. PCA Capture Mode
AT89C5130A/31A-M
14.216-bit Software Timer/Compare Mode
The PCA modules can be used as software timers by setting both the ECOM and MAT bits in
the modules CCAPMn register. The PCA timer will be compared to the module's capture registers and when a match occurs an interrupt will occur if the CCFn (CCON SFR) and the ECCFn
(CCAPMn SFR) bits for the module are both set (see Figure 14-4).
4337K–USB–04/08
65
AT89C5130A/31A-M
Figure 14-4. PCA Compare Mode and PCA Watchdog Timer
CHCL
CCAPnHCCAPnL
ECOMn
CCAPMn, n = 0 to 4
0xDA to 0xDE
CAPNn MATn TOGn PWMn ECCFnCAPPn
16-bit Comparator
Match
CCON
0xD8
PCA IT
Enable
PCA Counter/Timer
RESET
(1)
CIDLCPS1 CPS0ECF
CMOD
0xD9
WDTE
Reset
Write to
CCAPnL
Write to
CCAPnH
CFCCF2 CCF1 CCF0
CR
CCF3
CCF4
10
Note:1. Only for Module 4
Before enabling ECOM bit, CCAPnL and CCAPnH should be set with a non zero value, otherwise an unwanted match could happen. Writing to CCAPnH will set the ECOM bit.
Once ECOM set, writing CCAPnL will clear ECOM so that an unwanted match doesn’t occur
while modifying the compare value. Writing to CCAPnH will set ECOM. For this reason, user
software should write CCAPnL first, and then CCAPnH. Of course, the ECOM bit can still be
controlled by accessing to CCAPMn register.
14.3High Speed Output Mode
In this mode, the CEX output (on port 1) associated with the PCA module will toggle each time a
match occurs between the PCA counter and the module's capture registers. To activate this
mode the TOG, MAT, and ECOM bits in the modu le's CCAPMn SFR must be set (see
Figure 14-5).
A prior write must be done to CCAPnL and CCAPnH before writing the ECOMn bit.
66
4337K–USB–04/08
Figure 14-5. PCA High-speed Output Mode
CHCL
CCAPnHCCAPnL
ECOMn
CCAPMn, n = 0 to 4
0xDA to 0xDE
CAPNn MATn TOGn PWMn ECCFnCAPPn
16-bit Comparator
Match
CFCR
CCON
0xD8
CCF4 CCF3 CCF2 CCF1 CCF0
PCA IT
Enable
CEXn
PCA counter/timer
Write to
CCAPnH
Reset
Write to
CCAPnL
1
0
AT89C5130A/31A-M
Before enabling ECOM bit, CCAPnL and CCAPnH should be set with a non zero value, otherwise an unwanted match could happen.
Once ECOM set, writing CCAPnL will clear ECOM so that an unwanted match doesn’t occur
while modifying the compare value. Writing to CCAPnH will set ECOM. For this reason, user
software should write CCAPnL first, and then CCAPnH. Of course, the ECOM bit can still be
controlled by accessing to CCAPMn register.
14.4Pulse Width Modulator Mode
All of the PCA modules can be used as PWM outputs. Figure 14-6 shows the PWM function.
The frequency of the output depends on the source for the PCA timer. All of the modules will
have the same frequency of output because they all share the PCA timer. The duty cycle of each
module is independently variable using the module's capture register CCAPLn. When the value
of the PCA CL SFR is less than the value in the module's CCAPLn SFR the output will be low,
when it is equal to or greater than the output will be high. When CL overflows from FF to 00,
CCAPLn is reloaded with the value in CCAPHn. This allows updating the PWM without glitches.
The PWM and ECOM bits in the module's CCAPMn register must be set to enable the PWM
mode.
4337K–USB–04/08
67
AT89C5130A/31A-M
Figure 14-6. PCA PWM Mode
CL
CCAPnH
CCAPnL
ECOMn
CCAPMn, n = 0 to 4
0xDA to 0xDE
CAPNn MATn TOGn PWMn ECCFnCAPPn
8-bit Comparator
CEXn
“0”
“1”
≥
<
Enable
PCA Counter/Timer
Overflow
14.5PCA Watchdog Timer
An on-board watchdog timer is available with the PCA to improve the reliability of the system
without increasing chip count. Watchdog timers are useful for systems that are susceptible to
noise, power glitches, or electrostatic discharge. Module 4 is the only PCA module that can be
programmed as a watchdog. However, this module can still be used for other modes if the
watchdog is not needed. Figure 14-4 shows a diagram of how the watchdog works. The user
pre-loads a 16-bit value in the compare registers. Just like the other compare modes, this 16-bit
value is compared to the PCA timer value. If a match is allowed to occur, an internal reset will be
generated. This will not cause the RST
pin to be driven low.
In order to hold off the reset, the user has three options:
1.Periodically change the compare value so it will never match the PCA timer
2.Periodically change the PCA timer value so it will never match the compare values, or
3.Disable the watchdog by clearing the WDTE bit before a match occurs and then re-
The first two options are more reliable because the watchdog timer is never disabled as in option
#3. If the program counter ever goes astray, a match will eventually occur and cause an internal
reset. The second option is also not recommended if other PCA modules are being used.
Remember, the PCA timer is the time base for all modules; changing the time base for other
modules would not be a good idea. Thus, in most applications the first solution is the best option.
This watchdog timer won’t generate a reset out on the reset pin.
68
enable it
4337K–USB–04/08
15. Serial I/O Port
RITIRB8TB8RENSM2SM1SM0/FE
IDLPDGF0GF1POF-SMOD0SMOD1
To UART Framing Error Control
SM0 to UART Mode Control (SMOD0 = 0)
Set FE Bit if Stop Bit is 0 (framing error) (SMOD0 = 1)
SCON (98h)
PCON (87h)
Data Byte
RI
SMOD0 = X
Stop
Bit
Start
Bit
RXD
D7D6D5D4D3D2D1D0
FE
SMOD0 = 1
The serial I/O port in the AT89C5130A/31A-M is compatible with the serial I/O port in the 80C52.
It provides both synchronous and asynchronous communication modes. It operates as an Universal Asynchronous Receiver and Transmitter (UART) in three full-duplex modes (modes 1, 2
and 3). Asynchronous transmission and reception can occur simultaneously and at different
baud rates.
Serial I/O port includes the following enhancements:
• Framing error detection
• Automatic address recognition
15.1Framing Error Detection
Framing bit error detection is provided for the three asynchronous modes (modes 1, 2 and 3). To
enable the framing bit error detection feature, set SMOD0 bit in PCON register (see Figure 15-
1).
Figure 15-1. Framing Error Block Diagram
AT89C5130A/31A-M
4337K–USB–04/08
When this feature is enabled, the receiver checks each incoming data frame for a valid stop bit.
An invalid stop bit may result from noise on the serial lines or from simultaneous transmission by
two CPUs. If a valid stop bit is not found, the Framing Error bit (FE) in SCON register (See
15-1) bit is set.
Software may examine FE bit after each reception to check for data errors. Once set, only software or a reset can clear FE bit. Subsequently received frames with valid stop bits cannot clear
FE bit. When FE feature is enabled, RI rises on stop bit instead of the last data bit (See Figure
15-2 and Figure 15-3).
Figure 15-2. UART Timings in Mode 1
Table
69
AT89C5130A/31A-M
Figure 15-3. UART Timings in Modes 2 and 3
RI
SMOD0 = 0
Data ByteNinth
Bit
Stop
Bit
Start
Bit
RXD
D8D7D6D5D4D3D2D1D0
RI
SMOD0 = 1
FE
SMOD0 = 1
15.2Automatic Address Recognition
The automatic address recognition feature is enabled when the multiprocessor communication
feature is enabled (SM2 bit in SCON register is set).
Implemented in hardware, automatic address recognition enhances the multiprocessor communication feature by allowing the serial port to examine the address of each incoming command
frame. Only when the serial port recognizes its own address, the receiver sets RI bit in SCON
register to generate an interrupt. This ensures that the CPU is not interrupted by command
frames addressed to other devices.
If desired, you may enable the automatic address recognition feature in mode 1. In this configuration, the stop bit takes the place of the ninth data bit. Bit RI is set only when the received
command frame address matches the device’s address and is terminated by a valid stop bit.
15.2.1Given Address
To support automatic address recognition, a device is identified by a given address and a broadcast address.
Note:The multiprocessor communication and automatic address recognition features cannot be
enabled in mode 0 (i.e., setting SM2 bit in SCON register in mode 0 has no effect).
Each device has an individual address that is specified in SADDR register; the SADEN register
is a mask byte that contains don’t care bits (defined by zeros) to form the device’s given
address. The don’t care bits provide the flexibility to address one or more slaves at a time. The
following example illustrates how a given address is formed.
To address a device by its individual address, the SADEN mask byte must be 1111 1111b.
For example:
SADDR0101 0110b
SADEN1111 1100b
Given0101 01XXb
The following is an example of how to use given addresses to address different slaves:
Slave A:SADDR1111 0001b
SADEN1111 1010b
Given1111 0X0Xb
Slave B:SADDR1111 0011b
1111 1001b
SADEN
Given1111 0XX1b
70
4337K–USB–04/08
The SADEN byte is selected so that each slave may be addressed separately.
For slave A, bit 0 (the LSB) is a don’t care bit; for slaves B and C, bit 0 is a 1. To communicate
with slave A only, the master must send an address where bit 0 is clear (e.g. 1111 0000b).
For slave A, bit 1 is a 1; for slaves B and C, bit 1 is a don’t care bit. To communicate with slaves
B and C, but not slave A, the master must send an address with bits 0 and 1 both set (e.g. 11110011b).
To communicate with slaves A, B and C, the master must send an address with bit 0 set, bit 1
clear, and bit 2 clear (e.g. 1111 0001b).
15.2.2Broadcast Address
A broadcast address is formed from the logical OR of the SADDR and SADEN registers with
zeros defined as don’t care bits, e.g.:
AT89C5130A/31A-M
Slave C:SADDR1111 0011b
SADEN1111 1101b
Given1111 00X1b
SADDR0101 0110b
SADEN1111 1100b
Broadcast = SADDR OR SADEN1111 111Xb
The use of don’t care bits provides flexibility in defining the broadcast address, in most applications, a broadcast address is FFh. The following is an example of using broadcast addresses:
For slaves A and B, bit 2 is a don’t care bit; for slave C, bit 2 is set. To communicate with all of
the slaves, the master must send an address FFh. To communicate with slaves A and B, but not
slave C, the master can send and address FBh.
15.2.3Reset Addresses
On reset, the SADDR and SADEN registers are initialized to 00h, i.e. the given and broadcast
addresses are XXXX XXXXb (all don’t care bits). This ensures that the serial port will reply to any
address, and so, that it is backwards compatible with the 80C51 microcontrollers that do not
support automatic address recognition.
Slave A:SADDR1111 0001b
SADEN1111 1010b
Broadcast1111 1X11b,
Slave B:SADDR1111 0011b
1111 1001b
SADEN
Broadcast1111 1X11B,
Slave C:SADDR = 1111 0011b
SADEN1111 1101b
Broadcast1111 1111b
4337K–USB–04/08
71
AT89C5130A/31A-M
SADEN - Slave Address Mask Register (B9h)
RCLK
/ 16
RBCK
INT_BRG
0
1
TIMER1
0
1
0
1
TIMER2
INT_BRG
TIMER1
TIMER2
TIMER_BRG_RX
Rx Clock
/ 16
0
1
TIMER_BRG_TX
Tx Clock
TBCK
TCLK
76543210
Reset Value = 0000 0000b
Not bit addressable
SADDR - Slave Address Register (A9h)
76543210
Reset Value = 0000 0000b
Not bit addressable
15.3Baud Rate Selection for UART for Mode 1 and 3
The Baud Rate Generator for transmit and receive clocks can be selected separately via the
T2CON and BDRCON registers.
Figure 15-4. Baud Rate Selection
72
4337K–USB–04/08
15.3.1Baud Rate Selection Table for UART
BRG
0
1
/6
BRL
/2
0
1
INT_BRG
SPD
BRR
SMOD1
auto reload counter
overflow
Peripheral Clock
Baud_Rate =
2
SMOD1
x FCLK PERIPH
2 x 6
(1-SPD)
x 16 x [256 - (BRL)]
(BRL) = 256
-
2
SMOD1
x FCLK PERIPH
2 x 6
(1-SPD)
x 16 x Baud_Rate
AT89C5130A/31A-M
TCLK
(T2CON)
0000Timer 1Timer 1
1000Timer 2Timer 1
0100Timer 1Timer 2
1100Timer 2Timer 2
X010INT_BRGTimer 1
X110INT_BRGTimer 2
0X01Timer 1INT_BRG
1X01Timer 2INT_BRG
XX11INT_BRGINT_BRG
RCLK
(T2CON)
(BDRCON)
15.3.2Internal Baud Rate Generator (BRG)
When the internal Baud Rate Generator is used, the Baud Rates are determined by the BRG
overflow depending on the BRL reload value, the value of SPD bit (Speed Mode) in BDRCON
register and the value of the SMOD1 bit in PCON register.
Figure 15-5. Internal Baud Rate
TBCK
RBCK
(BDRCON)
Clock Source
UART Tx
Clock Source
UART Rx
4337K–USB–04/08
• The baud rate for UART is token by formula:
Table 15-1.SCON Register – SCON Serial Control Register (98h)
76543210
FE/SM0SM1SM2RENTB8RB8TIRI
73
AT89C5130A/31A-M
Bit
Number
Bit
MnemonicDescription
FE
7
SM0
6SM1
5SM2
4REN
3TB8
2RB8
Framing Error bit (SMOD0 = 1
Clear to reset the error state, not cleared by a valid stop bit.
Set by hardware when an invalid stop bit is detected.
SMOD0 must be set to enable access to the FE bit
Serial port Mode bit 0
Refer to SM1 for serial port mode selection.
SMOD0 must be cleared to enable access to the SM0 bit
Serial port Mode 2 bit/Multiprocessor Communication Enable bit
Clear to disable multiprocessor communication feature.
Set to enable multiprocessor communication feature in mode 2 and 3, and eventually
mode 1. This bit should be cleared in mode 0.
Reception Enable bit
Clear to disable serial reception.
Set to enable serial reception.
Transmitter Bit 8/Ninth bit to Transmit in Modes 2 and 3
Clear to transmit a logic 0 in the 9th bit.
Set to transmit a logic 1 in the 9th bit.
Receiver Bit 8/Ninth bit received in modes 2 and 3
Cleared by hardware if 9th bit received is a logic 0.
Set by hardware if 9th bit received is a logic 1.
In mode 1, if SM2 = 0, RB8 is the received stop bit. In mode 0 RB8 is not used.
)
CPU PERIPH
CPU PERIPH/
/6
32 or/16
Transmit Interrupt flag
1TI
0RI
Clear to acknowledge interrupt.
Set by hardware at the end of the 8th bit time in mode 0 or at the beginning of the stop bit
in the other modes.
Receive Interrupt flag
Clear to acknowledge interrupt.
Set by hardware at the end of the 8th bit time in mode 0, see Figure 15-2. and Figure 15-
3. in the other modes.
Reset Value = 0000 0000b
Bit addressable
74
4337K–USB–04/08
AT89C5130A/31A-M
Example of computed value when X2 = 1, SMOD1 = 1, SPD = 1
F
= 16.384 MHzF
Baud Rates
1152002471.232430.16
576002381.232300.16
384002291.232170.16
288002201.232040.16
192002030.631780.16
96001490.311000.16
4800431.23--
OSC
BRLError (%)BRLError (%)
Example of computed value when X2 = 0, SMOD1 = 0, SPD = 0
F
= 16.384 MHzF
OSC
Baud Rates
48002471.232430.16
BRLError (%)BRLError (%)
OSC
OSC
= 24 MHz
= 24 MHz
The baud rate generator can be used for mode 1 or 3 (refer to Figure 15-4.), but also for mode 0
for UART, thanks to the bit SRC located in BDRCON register (Table 15-4.)
15.4UART Registers
SADEN - Slave Address Mask Register for UART (B9h)
Reset Value = 0000 0000b
SADDR - Slave Address Register for UART (A9h)
Reset Value = 0000 0000b
24002381.232300.16
12002201.232023.55
6001850.161520.16
76543210
––––––––
76543210
––––––––
4337K–USB–04/08
SBUF - Serial Buffer Register for UART (99h)
76543210
––––––––
Reset Value = XXXX XXXXb
75
AT89C5130A/31A-M
BRL - Baud Rate Reload Register for the internal baud rate generator, UART (9Ah)
76543210
––––––––
Reset Value = 0000 0000b
Table 15-2.T2CON Register
T2CON - Timer 2 Control Register (C8h)
76543210
TF2EXF2RCLKTCLKEXEN2TR2C/T2#CP/RL2#
Bit
Number
7TF2
6EXF2
5RCLK
4TCLK
3EXEN2
2TR2
Bit
MnemonicDescription
Timer 2 overflow Flag
Must be cleared by software.
Set by hardware on Timer 2 overflow, if RCLK = 0 and TCLK = 0.
Timer 2 External Flag
Set when a capture or a reload is caused by a negative transition on T2EX pin if EXEN2
= 1.
When set, causes the CPU to vector to Timer 2 interrupt routine when Timer 2 interrupt is
enabled.
Must be cleared by software. EXF2 doesn’t cause an interrupt in Up/down counter mode
(DCEN = 1)
Receive Clock bit for UART
Cleared to use Timer 1 overflow as receive clock for serial port in mode 1 or 3.
Set to use Timer 2 overflow as receive clock for serial port in mode 1 or 3.
Transmit Clock bit for UART
Cleared to use Timer 1 overflow as transmit clock for serial port in mode 1 or 3.
Set to use Timer 2 overflow as transmit clock for serial port in mode 1 or 3.
Timer 2 External Enable bit
Cleared to ignore events on T2EX pin for Timer 2 operation.
Set to cause a capture or reload when a negative transition on T2EX pin is detected, if
Timer 2 is not used to clock the serial port.
Timer 2 Run control bit
Cleared to turn off Timer 2.
Set to turn on Timer 2.
Reset Value = 0000 0000b
Bit addressable
76
1C/T2#
0CP/RL2#
Timer/Counter 2 select bit
Cleared for timer operation (input from internal clock system: F
Set for counter operation (input from T2 input pin, falling edge trigger). Must be 0 for clock
out mode.
Timer 2 Capture/Reload bit
If RCLK = 1 or TCLK = 1, CP/RL2# is ignored and timer is forced to Auto-reload on Timer
2 overflow.
Cleared to Auto-reload on Timer 2 overflows or negative transitions on T2EX pin if
EXEN2 = 1.
Set to capture on negative transitions on T2EX pin if EXEN2 = 1.
CLK PERIPH
).
4337K–USB–04/08
AT89C5130A/31A-M
Table 15-3.PCON Register
PCON - Power Control Register (87h)
76543210
SMOD1SMOD0-POFGF1GF0PDIDL
Bit
Number
7SMOD1
6SMOD0
5-
4POF
3GF1
2GF0
1PD
0IDL
MnemonicDescription
Bit
Serial port Mode bit 1 for UART
Set to select double baud rate in mode 1, 2 or 3.
Serial port Mode bit 0 for UART
Cleared to select SM0 bit in SCON register.
Set to select FE bit in SCON register.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Power-Off Flag
Cleared to recognize next reset type.
Set by hardware when VCC rises from 0 to its nominal voltage. Can also be set by
software.
General-purpose Flag
Cleared by user for general-purpose usage.
Set by user for general-purpose usage.
General-purpose Flag
Cleared by user for general-purpose usage.
Set by user for general-purpose usage.
Power-down Mode Bit
Cleared by hardware when reset occurs.
Set to enter power-down mode.
Idle Mode Bit
Cleared by hardware when interrupt or reset occurs.
Set to enter idle mode.
4337K–USB–04/08
Reset Value = 00X1 0000b
Not bit addressable
Power-off flag reset value will be 1 only after a power on (cold reset). A warm reset doesn’t affect
the value of this bit.
Table 15-4.BDRCON Register
BDRCON - Baud Rate Control Register (9Bh)
76543210
---BRRTBCKRBCKSPDSRC
77
AT89C5130A/31A-M
Bit
Number
Bit
MnemonicDescription
7-
6-
5-
4BRR
3TBCK
2RBCK
1SPD
0SRC
Reserved
The value read from this bit is indeterminate. Do not set this bit
Reserved
The value read from this bit is indeterminate. Do not set this bit
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Baud Rate Run Control bit
Cleared to stop the internal Baud Rate Generator.
Set to start the internal Baud Rate Generator.
Transmission Baud rate Generator Selection bit for UART
Cleared to select Timer 1 or Timer 2 for the Baud Rate Generator.
Set to select internal Baud Rate Generator.
Reception Baud Rate Generator Selection bit for UART
Cleared to select Timer 1 or Timer 2 for the Baud Rate Generator.
Set to select internal Baud Rate Generator.
Baud Rate Speed Control bit for UART
Cleared to select the SLOW Baud Rate Generator.
Set to select the FAST Baud Rate Generator.
Baud Rate Source select bit in Mode 0 for UART
Cleared to select F
Set to select the internal Baud Rate Generator for UARTs in mode 0.
Reset Value = XXX0 0000b
Not bit addressable
/12 as the Baud Rate Generator (F
OSC
CLK PERIPH
/6 in X2 mode).
78
4337K–USB–04/08
16. Interrupt System
IE1
0
3
High priority
interrupt
Interrupt
Polling
Sequence, Decreasing From
High-to-Low Priority
Low Priority
Interrupt
Global DisableIndividual Enable
EXF2
TF2
TI
RI
TF0
INT0
INT1
TF1
IPH, IPL
IE0
0
3
0
3
0
3
0
3
0
3
0
3
PCA IT
KBD IT
SPI IT
0
3
0
3
0
3
UEPINT
USBINT
0
3
TWI IT
IT0
TCON.0
IT1
TCON.2
16.1Overview
The AT89C5130A/31A-M has a total of 11 interrupt vectors: two external interrupts (INT0 and
INT1), three timer interrupts (timers 0, 1 and 2), the serial port interrupt, SPI interrupt, Keyboard
interrupt, USB interrupt and the PCA global interrupt. These interrupts are shown in Figure 16-1.
Figure 16-1. Interrupt Control System
AT89C5130A/31A-M
Each of the interrupt sources can be individually enabled or disabled by setting or clearing a bit
in the Interrupt Enable register (
which must be cleared to disable all interrupts at once.
Table 16-2). This register also contains a global disable bit,
4337K–USB–04/08
79
AT89C5130A/31A-M
16.2Registers
Each interrupt source can also be individually programmed to one out of four priority levels by
setting or clearing a bit in the Interrupt Priority register (Table 16-3.) and in the Interrupt Priority
High register (Table 16-4). Table 16-1. shows the bit values and priority levels associated with
each combination.
The PCA interrupt vector is located at address 0033H, the SPI interrupt vector is located at
address 004BH and Keyboard interrupt vector is located at address 003BH. All other vectors
addresses are the same as standard C52 devices.
Table 16-1.Priority Level Bit Values
IPH.xIPL.xInterrupt Level Priority
000 (Lowest)
011
102
113 (Highest)
A low-priority interrupt can be interrupted by a high priority interrupt, but not by another low-priority interrupt. A high-priority interrupt can’t be interrupted by any other interrupt source.
If two interrupt requests of different priority levels are received simultaneously, the request of
higher priority level is serviced. If interrupt requests of the same priority level are received simultaneously, an internal polling sequence determines which request is serviced. Thus within each
priority level there is a second priority structure determined by the polling sequence.
The value read from this bit is indeterminate. Do not set this bit.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
Reserved
The value read from this bit is indeterminate. Do not set this bit.
SPI Interrupt Priority High bit
PSPIHPSPILPriority Level
00Lowest
01
10
11Highest
TWI Interrupt Priority High bit
PTWIHPTWILPriority Level
00Lowest
01
10
11Highest
86
Keyboard Interrupt Priority High bit
PKBHPKBLPriority Level
0PKBH
00Lowest
01
10
11Highest
Reset Value = X0XX X000b
Not bit addressable
4337K–USB–04/08
16.3Interrupt Sources and Vector Addresses
Table 16-8.Vector Table
AT89C5130A/31A-M
Number
00Reset0000h
11INT0IE00003h
22Timer 0TF0000Bh
33INT1IE10013h
44Timer 1IF1001Bh
56UARTRI+TI0023h
67Timer 2TF2+EXF2002Bh
75PCACF + CCFn (n = 0-4)0033h
88KeyboardKBDIT003Bh
99TWITWIIT0043h
1010SPISPIIT004Bh
11110053h
1212005Bh
13130063h
1414USBUEPINT + USBINT006Bh
Polling
Priority
Interrupt
Source
Interrupt
Request
Vector
Address
15150073h
4337K–USB–04/08
87
AT89C5130A/31A-M
17. Keyboard Interface
P1.0
Keyboard Interface
Interrupt Request
KBD
IE1.0
Input Circuitry
P1.1Input Circuitry
P1.2Input Circuitry
P1.3Input Circuitry
P1.4Input Circuitry
P1.5Input Circuitry
P1.6Input Circuitry
P1.7Input Circuitry
KBDIT
P1:x
KBE.x
KBF.x
KBLS.x
0
1
Vcc
Internal Pull-up
17.1Introduction
The AT89C5130A/31A-M implements a keyboard interface allowing the connection of a 8 x n
matrix keyboard. It is based on 8 inputs with programmable interrupt capability on both high or
low level. These inputs are available as an alternate function of P1 and allow to exit from idle
and power down modes.
17.2Description
The keyboard interface communicates with the C51 core through 3 special function registers:
KBLS, the Keyboard Level Selection register (Table 17-3), KBE, The Keyboard interrupt Enable
register (Table 17-2), and KBF, the Keyboard Flag register (Table 17-1).
17.2.1Interrupt
The keyboard inputs are considered as 8 independent interrupt sources sharing the same interrupt vector. An interrupt enable bit (KBD in IE1) allows global enable or disable of the keyboard
interrupt (see Figure 17-1). As detailed in Figure 17-2 each keyboard input has the capability to
detect a programmable level according to KBLS.x bit value. Level detection is then reported in
interrupt flags KBF.x that can be masked by software using KBE.x bits.
This structure allow keyboard arrangement from 1 by n to 8 by n matrix and allow usage of P1
inputs for other purpose.
Figure 17-1. Keyboard Interface Block Diagram
Figure 17-2. Keyboard Input Circuitry
88
4337K–USB–04/08
17.2.2Power Reduction Mode
P1 inputs allow exit from idle and power down modes as detailed in section “Power-down Mode”.
17.3Registers
Table 17-1.KBF Register
KBF - Keyboard Flag Register (9Eh)
76543210
KBF7KBF6KBF5KBF4KBF3KBF2KBF1 KBF0
Bit Number
7KBF7
6KBF6
AT89C5130A/31A-M
Bit
MnemonicDescription
Keyboard line 7 flag
Set by hardware when the Port line 7 detects a programmed level. It generates a
Keyboard interrupt request if the KBKBIE.7 bit in KBIE register is set.
Cleared by hardware when reading KBF SFR by software.
Keyboard line 6 flag
Set by hardware when the Port line 6 detects a programmed level. It generates a
Keyboard interrupt request if the KBIE.6 bit in KBIE register is set.
Cleared by hardware when reading KBF SFR by software.
5KBF5
4KBF4
3KBF3
2KBF2
1KBF1
0KBF0
Keyboard line 5 flag
Set by hardware when the Port line 5 detects a programmed level. It generates a
Keyboard interrupt request if the KBIE.5 bit in KBIE register is set.
Cleared by hardware when reading KBF SFR by software.
Keyboard line 4 flag
Set by hardware when the Port line 4 detects a programmed level. It generates a
Keyboard interrupt request if the KBIE.4 bit in KBIE register is set.
Cleared by hardware when reading KBF SFR by software.
Keyboard line 3 flag
Set by hardware when the Port line 3 detects a programmed level. It generates a
Keyboard interrupt request if the KBIE.3 bit in KBIE register is set.
Cleared by hardware when reading KBF SFR by software.
Keyboard line 2 flag
Set by hardware when the Port line 2 detects a programmed level. It generates a
Keyboard interrupt request if the KBIE.2 bit in KBIE register is set.
Cleared by hardware when reading KBF SFR by software.
Keyboard line 1 flag
Set by hardware when the Port line 1 detects a programmed level. It generates a
Keyboard interrupt request if the KBIE.1 bit in KBIE register is set.
Cleared by hardware when reading KBF SFR by software.
Keyboard line 0 flag
Set by hardware when the Port line 0 detects a programmed level. It generates a
Keyboard interrupt request if the KBIE.0 bit in KBIE register is set.
Cleared by hardware when reading KBF SFR by software.
Cleared to enable a low level detection on Port line 7.
Set to enable a high level detection on Port line 7.
Keyboard line 6 Level Selection bit
Cleared to enable a low level detection on Port line 6.
Set to enable a high level detection on Port line 6.
Keyboard line 5 Level Selection bit
Cleared to enable a low level detection on Port line 5.
Set to enable a high level detection on Port line 5.
Keyboard line 4 Level Selection bit
Cleared to enable a low level detection on Port line 4.
Set to enable a high level detection on Port line 4.
Keyboard line 3 Level Selection bit
Cleared to enable a low level detection on Port line 3.
Set to enable a high level detection on Port line 3.
Keyboard line 2 Level Selection bit
Cleared to enable a low level detection on Port line 2.
Set to enable a high level detection on Port line 2.
Keyboard line 1 Level Selection bit
Cleared to enable a low level detection on Port line 1.
Set to enable a high level detection on Port line 1.
0KBLS0
Keyboard line 0 Level Selection bit
Cleared to enable a low level detection on Port line 0.
Set to enable a high level detection on Port line 0.
Reset Value = 0000 0000b
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91
AT89C5130A/31A-M
18. Programmable LED
AT89C5130A/31A-M have up to 4 programmable LED current sources, configured by the register LEDCON.
Table 18-1.LEDCON Register
LEDCON (S:F1h) LED Control Register
76543210
LED3LED2LED1LED0
Bit Number
7:6LED3
5:4LED2
3:2LED1
1:0LED0
Bit
MnemonicDescription
Reset Value = 00h
PortLED3Configuration
00Standard C51 Port
01 2 mA current source when P3.7 is low
10 4 mA current source when P3.7 is low
11 10 mA current source when P3.7 is low
Port/LED2 Configuration
00 Standard C51 Port
01 2 mA current source when P3.6 is low
10 4 mA current source when P3.6 is low
11 10 mA current source when P3.6 is low
Port/LED1Configuration
00 Standard C51 Port
01 2 mA current source when P3.5 is low
10 4 mA current source when P3.5 is low
11 10 mA current source when P3.5 is low
Port/LED0Configuration
00 Standard C51 Port
01 2 mA current source when P3.3 is low
10 4 mA current source when P3.3 is low
11 10 mA current source when P3.3 is low
92
4337K–USB–04/08
19. Serial Peripheral Interface (SPI)
Slave 1
MISO
MOSI
SCK
SS
MISO
MOSI
SCK
SS
PORT
0
1
2
3
Slave 3
MISO
MOSI
SCK
SS
Slave 4
MISO
MOSI
SCK
SS
Slave 2
MISO
MOSI
SCK
SS
VDD
Master
The Serial Peripheral Interface module (SPI) allows full-duplex, synchronous, serial communication between the MCU and peripheral devices, including other MCUs.
19.1Features
Features of the SPI module include the following:
• Full-duplex, three-wire synchronous transfers
• Master or Slave operation
• Eight programmable Master clock rates
• Serial clock with programmable polarity and phase
• Master mode fault error flag with MCU interrupt capability
• Write collision flag protection
19.2Signal Description
Figure 19-1 shows a typical SPI bus configuration using one Master controller and many Slave
peripherals. The bus is made of three wires connecting all the devices:
AT89C5130A/31A-M
Figure 19-1. SPI Master/Slaves Interconnection
The Master device selects the individual Slave devices by using four pins of a parallel port to
control the four SS
19.2.1Master Output Slave Input (MOSI)
This 1-bit signal is directly connected between the Master Device and a Slave Device. The MOSI
line is used to transfer data in series from the Master to the Slave. Therefore, it is an output signal from the Master, and an input signal to a Slave. A byte (8-bit word) is transmitted most
significant bit (MSB) first, least significant bit (LSB) last.
19.2.2Master Input Slave Output (MISO)
This 1-bit signal is directly connected between the Slave Device and a Master Device. The MISO
line is used to transfer data in series from the Slave to the Master. Therefore, it is an output signal from the Slave, and an input signal to the Master. A byte (8-bit word) is transmitted most
significant bit (MSB) first, least significant bit (LSB) last.
pins of the Slave devices.
4337K–USB–04/08
93
AT89C5130A/31A-M
19.2.3SPI Serial Clock (SCK)
This signal is used to synchronize the data movement both in and out the devices through their
MOSI and MISO lines. It is driven by the Master for eight clock cycles which allows to exchange
one byte on the serial lines.
19.2.4Slave Select (SS)
Each Slave peripheral is selected by one Slave Select pin (SS). This signal must stay low for any
message for a Slave. It is obvious that only one Master (SS
The Master may select each Slave device by software through port pins (Figure 19-1). To prevent bus conflicts on the MISO line, only one slave should be selected at a time by the Master
for a transmission.
In a Master configuration, the SS line can be used in conjunction with the MODF flag in the SPI
Status register (SP STA) to pre vent mult iple masters fro m driving MOSI and S CK (see
Section “Error Conditions”, page 98).
A high level on the SS pin puts the MISO line of a Slave SPI in a high-impedance state.
The SS pin could be used as a general-purpose if the following conditions are met:
• The device is configured as a Master and the SSDIS control bit in SPCON is set. This kind of
configuration can be found when only one Master is driving the network and there is no way
that the SS pin could be pulled low. Therefore, the MODF flag in the SPSTA will never be
(1)
set
• The Device is configured as a Slave with CPHA and SSDIS control bits set
configuration can happen when the system comprises one Master and one Slave only.
Therefore, the device should always be selected and there is no reason that the Master uses
the SS pin to select the communicating Slave device.
Notes:1. Clearing SSDIS control bit does not clear MODF.
high level) can drive the network.
.
(2)
This kind of
2. Special care should be taken not to set SSDIS control bit when CPHA =’0’ because in this
mode, the SS is used to start the transmission.
19.2.5Baud Rate
94
In Master mode, the baud rate can be selected from a baud rate generator which is controlled by
three bits in the SPCON register: SPR2, SPR1 and SPR0. The Master clock is chosen from one
of seven clock rates resulting from the division of the internal clock by 4, 8, 16, 32, 64 or 128.
Table 19-1 gives the different clock rates selected by SPR2:SPR1:SPR0:
Table 19-1.SPI Master Baud Rate Selection
SPR2SPR1SPR0Clock RateBaud Rate Divisor (BD)
000Don’t UseNo BRG
001F
010F
011F
100F
101F
110F
CLK PERIPH
CLK PERIPH
CLK PERIPH
CLK PERIPH
CLK PERIPH
CLK PERIPH
/44
/88
/1616
/3232
/6464
/128128
4337K–USB–04/08
SPR2SPR1SPR0Clock RateBaud Rate Divisor (BD)
Shift Register
01
234567
Internal Bus
Pin
Control
Logic
MISO
MOSI
SCK
M
S
Clock
Logic
Clock
Divider
Clock
Select
/4
/64
/128
SPI Interrupt Request
8-bit bus
1-bit signal
SS
FCLK PERIPH
/32
/8
/16
Receive Data Register
SPDAT
SPI
Control
SPSTA
CPHA
SPR0
SPR1
CPOLMSTRSSDISSPEN
SPR2
SPCON
WCOLMODFSPIF
----
SSERR
111Don’t UseNo BRG
19.3Functional Description
Figure 19-2 shows a detailed structure of the SPI module.
Figure 19-2. SPI Module Block Diagram
AT89C5130A/31A-M
19.3.1Operating Modes
4337K–USB–04/08
The Serial Peripheral Interface can be configured as one of the two modes: Master mode or
Slave mode. The configuration and initialization of the SPI module is made through one register:
• The Serial Peripheral CONtrol register (SPCON)
Once the SPI is configured, the data exchange is made using:
• SPCON
• The Serial Peripheral STAtus register (SPSTA)
• The Serial Peripheral DATa register (SPDAT)
During an SPI transmission, data is simultaneously transmitted (shifted out serially) and
received (shifted in serially). A serial clock line (SCK) synchronizes shifting and sampling on the
two serial data lines (MOSI and MISO). A Slave Select line (SS
Slave SPI device; Slave devices that are not selected do not interfere with SPI bus activities.
) allows individual selection of a
95
AT89C5130A/31A-M
19.3.1.1Master Mode
8-bit Shift Register
SPI
Clock Generator
Master MCU
8-bit Shift Register
MISOMISO
MOSI
MOSI
SCKSCK
VSS
VDD
SSSS
Slave MCU
When the Master device transmits data to the Slave device via the MOSI line, the Slave device
responds by sending data to the Master device via the MISO line. This implies full-duplex transmission with both data out and data in synchronized with the same clock (Figure 19-3).
The SPI operates in Master mode when the Master bit, MSTR
, in the SPCON register is set.
Only one Master SPI device can initiate transmissions. Software begins the transmission from a
Master SPI module by writing to the Serial Peripheral Data Register (SPDAT). If the shift register
is empty, the byte is immediately transferred to the shift register. The byte begins shifting out on
MOSI pin under the control of the serial clock, SCK. Simultaneously, another byte shifts in from
the Slave on the Master’s MISO pin. The transmission ends when the Serial Peripheral transfer
data flag, SPIF, in SPSTA becomes set. At the same time that SPIF becomes set, the received
byte from the Slave is transferred to the receive data register in SPDAT. Software clears SPIF
by reading the Serial Peripheral Status register (SPSTA) with the SPIF bit set, and then reading
the SPDAT.
19.3.1.2Slave Mode
The SPI operates in Slave mode when the Master bit, MSTR
cleared. Before a data transmission occurs, the Slave Select pin, SS, of the Slave device must
be set to’0’. SS must remain low until the transmission is complete.
In a Slave SPI module, data enters the shift register under the control of the SCK from the Master SPI module. After a byte enters the shift register, it is immediately transferred to the receive
data register in SPDAT, and the SPIF bit is set. To prevent an overflow condition, Slave software
must then read the SPDAT before another byte enters the shift register
complete the write to the SPDAT (shift register) at least one bus cycle before the Master SPI
starts a transmission. If the write to the data register is late, the SPI transmits the data already in
the shift register from the previous transmission.
19.3.2Transmission Formats
Software can select any of four combinations of serial clock (SCK) phase and polarity using two
bits in the SPCON: the Clock POLarity (CPOL
the default SCK line level in idle state. It has no significant effect on the transmission format.
CPHA defines the edges on which the input data are sampled and the edges on which the
1.The SPI module should be configured as a Master before it is enabled (SPEN set). Also the Mas-
2.The SPI module should be configured as a Slave before it is enabled (SPEN set).
3.The maximum frequency of the SCK for an SPI configured as a Slave is
96
4.Before writing to the CPOL and CPHA bits, the SPI should be disabled (SPEN =’0’).
(4)
) and the Clock PHAse (CPHA4). CPOL defines
ter SPI should be configured before the Slave SPI.
(2)
, in the SPCON register is
(3)
. A Slave SPI must
F
CLK PERIPH
/2
.
4337K–USB–04/08
output data are shifted (Figure 19-4 and Figure 19-5). The clock phase and polarity should be
MSBbit6bit5bit4bit3bit2bit1LSB
bit6bit5bit4bit3bit2bit1MSBLSB
13245678
Capture point
SS (to Slave)
MISO (from Slave)
MOSI (from Master)
SCK (CPOL = 1)
SCK (CPOL = 0)
SPEN (internal)
SCK cycle number
MSBbit6bit5bit4bit3bit2bit1LSB
bit6bit5bit4bit3bit2bit1
MSBLSB
13245678
Capture point
SS (to Slave)
MISO (from Slave)
MOSI (from Master)
SCK (CPOL = 1)
SCK (CPOL = 0)
SPEN (internal)
SCK cycle number
Byte 1Byte 2
Byte 3
MISO/MOSI
Master SS
Slave SS
(CPHA = 1)
Slave SS
(CPHA = 0)
identical for the Master SPI device and the communicating Slave device.
Figure 19-4. Data Transmission Format (CPHA = 0)
Figure 19-5. Data Transmission Format (CPHA = 1)
AT89C5130A/31A-M
Figure 19-6. CPHA/SS
4337K–USB–04/08
Timing
As shown in Figure 19-5, the first SCK edge is the MSB capture strobe. Therefore the Slave
must begin driving its data before the first SCK edge, and a falling edge on the SS pin is used to
start the transmission. The SS pin must be toggled high and then low between each byte transmitted (Figure 19-2).
Figure 19-6 shows an SPI transmission in which CPHA is’1’. In this case, the Master begins driv-
ing its MOSI pin on the first SCK edge. Therefore the Slave uses the first SCK edge as a start
transmission signal. The SS
pin can remain low between transmissions (Figure 19-1). This format may be preferable in systems having only one Master and only one Slave driving the MISO
data line.
97
AT89C5130A/31A-M
19.3.3Error Conditions
The following flags in the SPSTA signal SPI error conditions:
19.3.3.1Mode Fault (MODF)
Mode Fault error in Master mode SPI indicates that the level on the Slave Select (SS) pin is
inconsistent with the actual mode of the device. MODF is set to warn that there may have a
multi-master conflict for system control. In this case, the SPI system is affected in the following
ways:
• An SPI receiver/error CPU interrupt request is generated,
• The SPEN bit in SPCON is cleared. This disable the SPI,
• The MSTR bit in SPCON is cleared
When SS
SS signal becomes “0”.
However, as stated before, for a system with one Master, if the SS pin of the Master device is
pulled low, there is no way that another Master attempt to drive the network. In this case, to prevent the MODF flag from being set, software can set the SSDIS bit in the SPCON register and
therefore making the SS pin as a general-purpose I/O pin.
Clearing the MODF bit is accomplished by a read of SPSTA register with MODF bit set, followed
by a write to the SPCON register. SPEN Control bit may be restored to its original set state after
the MODF bit has been cleared.
DISable (SSDIS) bit in the SPCON register is cleared, the MODF flag is set when the
19.3.3.2Write Collision (WCOL)
A Write Collision (WCOL) flag in the SPSTA is set when a write to the SPDAT register is done
during a transmit sequence.
WCOL does not cause an interruption, and the transfer continues uninterrupted.
Clearing the WCOL bit is done through a software sequence of an access to SPSTA and an
access to SPDAT.
19.3.3.3Overrun Condition
An overrun condition occurs when the Master device tries to send several data bytes and the
Slave devise has not cleared the SPIF bit issuing from the previous data byte transmitted. In this
case, the receiver buffer contains the byte sent after the SPIF bit was last cleared. A read of the
SPDAT returns this byte. All others bytes are lost.
This condition is not detected by the SPI peripheral.
19.3.4Interrupts
Two SPI status flags can generate a CPU interrupt requests:
Table 19-2.SPI Interrupts
FlagRequest
SPIF (SP Data Transfer)SPI Transmitter Interrupt request
Serial Peripheral data transfer flag, SPIF: This bit is set by hardware when a transfer has been
completed. SPIF bit generates transmitter CPU interrupt requests.
98
4337K–USB–04/08
Mode Fault flag, MODF: This bit becomes set to indicate that the level on the SS is inconsistent
SSDIS
MODF
CPU Interrupt Request
SPI Receiver/Error
CPU Interrupt Request
SPI Transmitter
SPI
CPU Interrupt Request
SPIF
with the mode of the SPI. MODF with SSDIS reset, generates receiver/error CPU interrupt
requests.
Figure 19-7 gives a logical view of the above statements.
Figure 19-7. SPI Interrupt Requests Generation
19.3.5Registers
There are three registers in the module that provide control, status and data storage functions. These registers are
describes in the following paragraphs.
19.3.5.1Serial Peripheral Control Register (SPCON)
• The Serial Peripheral Control Register does the following:
– Selects one of the Master clock rates
– Configure the SPI module as Master or Slave
– Selects serial clock polarity and phase
– Enables the SPI module
– Frees the SS pin for a general-purpose
Table 19-3 describes this register and explains the use of each bit.
AT89C5130A/31A-M
Table 19-3.SPCON Register
76543210
SPR2SPENSSDISMSTRCPOLCPHASPR1SPR0
Bit
NumberBit MnemonicDescription
7SPR2
6SPEN
5SSDIS
4MSTR
3CPOL
Serial Peripheral Rate 2
Bit with SPR1 and SPR0 define the clock rate.
Serial Peripheral Enable
Cleared to disable the SPI interface.
Set to enable the SPI interface.
SS Disable
Cleared to enable SS in both Master and Slave modes.
Set to disable SS in both Master and Slave modes. In Slave mode, this bit has no
effect if CPHA = “0”.
Serial Peripheral Master
Cleared to configure the SPI as a Slave.
Set to configure the SPI as a Master.
Clock Polarity
Cleared to have the SCK set to “0” in idle state.
Set to have the SCK set to “1” in idle state.
4337K–USB–04/08
99
AT89C5130A/31A-M
Bit
NumberBit MnemonicDescription
Clock Phase
2CPHA
1SPR1
0SPR0
Cleared to have the data sampled when the SCK leaves the idle state (see CPOL).
Set to have the data sampled when the SCK returns to idle state (see CPOL).
SPR2 SPR1 SPR0 Serial Peripheral Rate
000Reserved
00 1F
010 F
011F
100F
10 1F
110F
1 11Reserved
Reset Value = 0001 0100b
Not bit addressable
19.3.5.2Serial Peripheral Status Register (SPSTA)
The Serial Peripheral Status Register contains flags to signal the following conditions:
• Data transfer complete
• Write collision
• Inconsistent logic level on SS pin (mode fault error)
Table 19-4 describes the SPSTA register and explains the use of every bit in the register.
CLK PERIPH/
CLK PERIPH/
CLK PERIPH/
CLK PERIPH/
CLK PERIPH/
CLK PERIPH/
4
8
16
32
64
128
Table 19-4.SPSTA Register
SPSTA - Serial Peripheral Status and Control register (0C4H)
76543210
SPIFWCOL
Bit Number
7SPIF
6WCOL
5SSERR
Bit
MnemonicDescription
SSERR
Serial Peripheral data transfer flag
Cleared by hardware to indicate data transfer is in progress or has been approved by a
clearing sequence.
Set by hardware to indicate that the data transfer has been completed.
Write Collision flag
Cleared by hardware to indicate that no collision has occurred or has been approved by a
clearing sequence.
Set by hardware to indicate that a collision has been detected.
Synchronous Serial Slave Error flag
Set by hardware when SS is de-
asserted before the end of a received data.
Cleared by disabling the SPI (clearing SPEN bit in SPCON).
MODF----
100
4337K–USB–04/08
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