Microchip Technology Inc PIC12C508-JW, PIC12C508A-04-P, PIC12C508A-04-SM, PIC12C508A-04-SN, PIC12C509-JW Datasheet

...
1998 Microchip Technology Inc. DS40139D-page 1
Devices included in this Data Sheet:
• PIC12C508 • PIC12C508A
• PIC12C509 • PIC12C509A
Note: Throughout this data sheet PIC12C508(A)
refers to the PIC12C508 and PIC12C508A. PIC12C509(A) refers to the PIC12C509 and PIC12C509A. PIC12C5XX refers to the PIC12C508, PIC12C508A, PIC12C509 and PIC12C509A.
High-Performance RISC CPU:
• Only 33 single word instructions to learn
• All instructions are single cycle (1 µ s) except for program branches which are two-cycle
• Operating speed: DC - 4 MHz clock input
DC - 1 µ s instruction cycle
• 12-bit wide instructions
• 8-bit wide data path
• Seven special function hardware registers
• Two-level deep hardware stack
• Direct, indirect and relative addressing modes for data and instructions
• Internal 4 MHz RC oscillator with programmable calibration
• In-circuit serial programming
Peripheral Features:
• 8-bit real time clock/counter (TMR0) with 8-bit programmable prescaler
• Power-On Reset (POR)
• Device Reset Timer (DRT)
• Watchdog Timer (WDT) with its own on-chip RC oscillator for reliable operation
• Programmable code-protection
• Power saving SLEEP mode
• Wake-up from SLEEP on pin change
• Internal weak pull-ups on I/O pins
• Internal pull-up on MCLR
pin
• Selectable oscillator options:
- INTRC: Internal 4 MHz RC oscillator
Device EPROM RAM
PIC12C508 512 x 12 25 PIC12C508A 512 x 12 25 PIC12C509 1024 x 12 41 PIC12C509A 1024 x 12 41
- EXTRC: External low-cost RC oscillator
- XT: Standard crystal/resonator
- LP: Power saving, low frequency crystal
CMOS Tec hnology:
• Low power, high speed CMOS EPROM technology
• Fully static design
• Wide operating voltage range
• Wide temperature range:
- Commercial: 0 ° C to +70 ° C
- Industrial: -40 ° C to +85 ° C
- Extended: -40 ° C to +125 ° C
• Low power consumption
- < 2 mA @ 5V, 4 MHz
- 15 µ A typical @ 3V, 32 KHz
- < 1 µ A typical standby current
Pin Diagram
PDIP, SOIC, Windowed Ceramic Side Brazed
8
7
6
5
1
2
3
4
PIC12C508(A
)
VSS GP0 GP1 GP2/T0CKI
PIC12C509(A)
GP5/OSC1/CLKIN
GP4/OSC2
GP3/MCLR
/VPP
VDD
PIC12C5XX
8-Pin, 8-Bit CMOS Microcontroller
PIC12C5XX
DS40139D-page 2
1998 Microchip Technology Inc.
Device Differences
Note 1: If you change from the PIC12C50X to the PIC12C50XA, please verify oscillator characteristics in your appli-
cation.
Note 2: See Section 7.2.5 for OSCCAL implementation differences.
Device
Voltage
Range
Oscillator
Oscillator
Calibration
2
Process
Technology
(Microns)
PIC12C508A 3.0-5.5 See Note 1 6 0.7 PIC12LC508A 2.5-5.5 See Note 1 6 0.7 PIC12C508 2.5-5.5 See Note 1 4 0.9 PIC12C509A 3.0-5.5 See Note 1 6 0.7 PIC12LC509A 2.5-5.5 See Note 1 6 0.7 PIC12C509 2.5-5.5 See Note 1 4 0.9
1998 Microchip Technology Inc. DS40139D-page 3
PIC12C5XX
TABLE OF CONTENTS
1.0 General Description......................................................................................................................................................................4
2.0 PIC12C5XX Device Varieties.......................................................................................................................................................7
3.0 Architectural Overview .................................................................................................................................................................9
4.0 Memory Organization................................................................................................................................................................ 13
5.0 I/O Port...................................................................................................................................................................................... 21
6.0 Timer0 Module and TMR0 Register.......................................................................................................................................... 23
7.0 Special Features of the CPU..................................................................................................................................................... 27
8.0 Instruction Set Summary........................................................................................................................................................... 39
9.0 Development Support................................................................................................................................................................ 51
10.0 Electrical Characteristics - PIC12C508/PIC12C509/PIC12LC508/PIC12LC509 ...................................................................... 57
11.0 DC and AC Characteristics - PIC12C508/PIC12C509/PIC12LC508/PIC12LC509................................................................... 73
12.0 Electrical Characteristics - PIC12C508A/PIC12C509A/PIC12LC508A/PIC12LC509A............................................................. 77
13.0 DC and AC Characteristics - PIC12C508A/PIC12C509A/PIC12LC508A/PIC12LC509A......................................................... 91
14.0 Packaging Information............................................................................................................................................................... 95
INDEX................................................................................................................................................................................................ 101
PIC12C5XX Product Identification System........................................................................................................................................ 105
To Our Valued Customers
Most Current Data Sheet
To obtain the most up-to-date version of this data sheet, please check our Worldwide Web site at:
http://www.microchip.com
You can determine the version of a data sheet by examining its literature number found on the bottom outside corner of any page. The last character of the literature number is the version number. e.g., DS30000A is version A of document DS30000.
Errata
An errata sheet may exist for current devices, describing minor operational differences (from the data sheet) and recommended workarounds. As de vice/documentation issues become known to us , we will publish an err ata sheet. The err ata will specify the revi­sion of silicon and revision of document to which it applies.
To determine if an errata sheet exists for a particular device, please check with one of the following:
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• The Microchip Corporate Literature Center; U.S. FAX: (602) 786-7277
When contacting a sales office or the literature center, please specify which device, revision of silicon and data sheet (include lit­erature number) you are using.
Corrections to this Data Sheet
We constantly strive to improve the quality of all our products and documentation. We have spent a great deal of time to ensure that this document is correct. How e ver, we realize that w e may have missed a fe w things . If you find any inf ormation that is missing or appears in error, please:
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PIC12C5XX
DS40139D-page 4
1998 Microchip Technology Inc.
1.0 GENERAL DESCRIPTION
The PIC12C5XX from Microchip Technology is a family of low-cost, high performance, 8-bit, fully static, EPROM/ROM-based CMOS microcontrollers. It employs a RISC architecture with only 33 single word/ single cycle instructions. All instructions are single cycle (1 µ s) except for program branches which take two cycles. The PIC12C5XX delivers perfor mance an order of magnitude higher than its competitors in the same price category. The 12-bit wide instructions are highly symmetrical resulting in 2:1 code compression over other 8-bit microcontrollers in its class. The easy to use and easy to remember instruction set reduces development time significantly.
The PIC12C5XX products are equipped with special features that reduce system cost and power require­ments. The Power-On Reset (POR) and Device Reset Timer (DRT) eliminate the need for external reset cir­cuitry. There are four oscillator configurations to choose from, including INTRC internal oscillator mode and the power-saving LP (Low Power) oscillator mode. Power saving SLEEP mode, Watchdog Timer and code protection features also improve system cost, power and reliability.
The PIC12C5XX are available in the cost-effective One-Time-Programmable (OTP) versions which are suitable for production in any volume. The customer can take full advantage of Microchip’s price leadership in OTP microcontrollers while benefiting from the O TP’s flexibility .
The PIC12C5XX products are supported by a full-fea­tured macro assembler, a software simulator, an in-cir­cuit emulator, a ‘C’ compiler, fuzzy logic support tools, a low-cost development programmer, and a full fea­tured programmer. All the tools are supported on IBM
PC and compatible machines.
1.1 Applications
The PIC12C5XX series fits perfectly in applications ranging from personal care appliances and security systems to low-power remote transmitters/receivers. The EPROM technology makes customizing applica­tion programs (transmitter codes, appliance settings, receiver frequencies, etc.) extremely fast and conve­nient. The small footprint packages, f or through hole or surface mounting, make this microcontroller series per­fect for applications with space limitations. Low-cost, low-power, high performance, ease of use and I/O flex­ibility make the PIC12C5XX series very versatile even in areas where no microcontroller use has been considered before (e.g., timer functions, replacement of “glue” logic and PLD’s in larger systems, coproces­sor applications).
1998 Microchip Technology Inc. DS40139D-page 5
PIC12C5XX
TABLE 1-1: PIC12CXXX & PIC12CEXXX FAMILY OF DEVICES
PIC12C508(A)
PIC12C509(A) PIC12CE518 PIC12CE519 PIC12C671 PIC12C672 PIC12CE673 PIC12CE674
Clock
Maximum Frequency of Operation (MHz)
4 4 4 4 10 10 10 10
Memory
EPROM Program Memory
512 x 12 1024 x 12 512 x 12 1024 x 12 1024 x 14 2048 x 14 1024 x 14 2048 x 14
RAM Data Memory (bytes)
25 41 25 41 128 128
128 128
Peripherals
EEPROM Data Memory (bytes)
16 16
16 16
Timer Module(s)
TMR0 TMR0 TMR0 TMR0 TMR0 TMR0 TMR0 TMR0
A/D Con­verter (8-bit) Channels
4 4 4 4
Features
Wake-up from SLEEP on pin change
Yes Yes Yes Yes Yes Yes Yes Yes
Interrupt Sources
4 4 4 4
I/O Pins 5 5 5 5 5 5 5 5 Input Pins 1 1 1 1 1 1 1 1 Internal
Pull-ups
Yes Yes Yes Yes Yes Yes Yes Yes
In-Circuit Serial Programming
Yes Yes Yes Yes Yes Yes Yes Yes
Number of Instructions
33 33 33 33 35 35 35 35
Packages 8-pin DIP,
JW, SOIC
8-pin DIP, JW, SOIC
8-pin DIP, JW, SOIC
8-pin DIP, JW, SOIC
8-pin DIP, JW, SOIC
8-pin DIP, JW, SOIC
8-pin DIP, JW8-pin DIP,
JW
All PIC12CXXX & PIC12CEXXX devices have Power-on Reset, selectable Watchdog Timer, selectable code protect and high I/O current capability. All PIC12CXXX & PIC12CEXXX devices use serial programming with data pin GP0 and clock pin GP1.
PIC12C5XX
DS40139D-page 6
1998 Microchip Technology Inc.
NOTES:
1998 Microchip Technology Inc. DS40139D-page 7
PIC12C5XX
2.0 PIC12C5XX DEVICE VARIETIES
A variety of packaging options are available. Depending on application and production requirements, the proper device option can be selected using the information in this section. When placing orders, please use the PIC12C5XX Product Identification System at the back of this data sheet to specify the correct part number.
2.1 UV Erasab
le Devices
The UV erasable version, offered in ceramic side brazed package, is optimal for prototype development and pilot programs.
The UV erasable version can be erased and reprogrammed to any of the configuration modes.
Microchip's PICSTART
PLUS and PRO MATE
pro­grammers all support programming of the PIC12C5XX. Third party programmers also are available; ref er to the
Microchip
Third Party Guide
for a list of sources.
2.2 One-Time-Pr
ogrammable (OTP)
Devices
The availability of OTP devices is especially useful for customers who need the flexibility for frequent code updates or small volume applications.
The OTP devices , packaged in plastic pac kages permit the user to program them once. In addition to the program memory, the configuration bits must also be programmed.
Note: Please note that erasing the device will
also erase the pre-programmed internal calibration value for the internal oscillator. The calibration value must be saved prior to erasing the part.
2.3 Quic
k-Turnaround-Production (QTP)
Devices
Microchip offers a QTP Programming Service for factory production orders. This service is made available for users who choose not to program a medium to high quantity of units and whose code patterns have stabilized. The devices are identical to the OTP devices b ut with all EPROM locations and fuse options already programmed by the factory. Certain code and prototype verification procedures do apply before production shipments are av ailable. Please con­tact your local Microchip Technology sales office for more details.
2.4 Serializ
ed Quick-Turnaround
Production (SQTP
SM
) De
vices
Microchip offers a unique programming service where a few user-defined locations in each device are programmed with different serial numbers. The serial numbers may be random, pseudo-random or sequential.
Serial programming allows each device to have a unique number which can serve as an entry-code, password or ID number.
PIC12C5XX
DS40139D-page 8
1998 Microchip Technology Inc.
NOTES:
1998 Microchip Technology Inc. DS40139D-page 9
PIC12C5XX
3.0 ARCHITECTURAL OVERVIEW
The high performance of the PIC12C5XX family can be attributed to a number of architectural features commonly found in RISC microprocessors. To begin with, the PIC12C5XX uses a Harvard architecture in which program and data are accessed on separate buses. This improves bandwidth over traditional von Neumann architecture where program and data are fetched on the same bus. Separating program and data memory further allows instructions to be sized differently than the 8-bit wide data word. Instruction opcodes are 12-bits wide making it possible to have all single word instructions. A 12-bit wide program memory access bus fetches a 12-bit instruction in a single cycle. A two-stage pipeline overlaps fetch and execution of instructions. Consequently, all instructions (33) execute in a single cycle (1 µ s @ 4MHz) except for program branches.
The table below lists program memory (EPROM) and data memory (RAM) for each PIC12C5XX device.
The PIC12C5XX can directly or indirectly address its register files and data memory. All special function registers including the program counter are mapped in the data memory. The PIC12C5XX has a highly orthogonal (symmetrical) instruction set that makes it possible to carry out any operation on any register using any addressing mode. This symmetrical nature and lack of ‘special optimal situations’ make programming with the PIC12C5XX simple yet efficient. In addition, the learning curve is reduced significantly.
Device EPROM RAM
PIC12C508 512 x 12 25 PIC12C508A 512 x 12 25 PIC12C509 1024 x 12 41 PIC12C509A 1024 x 12 41
The PIC12C5XX device contains an 8-bit ALU and working register. The ALU is a general purpose arithmetic unit. It performs arithmetic and Boolean functions between data in the working register and any register file.
The ALU is 8-bits wide and capable of addition, subtraction, shift and logical operations. Unless otherwise mentioned, arithmetic operations are two's complement in nature. In two-operand instructions, typically one operand is the W (working) register. The other operand is either a file register or an immediate constant. In single operand instructions, the operand is either the W register or a file register.
The W register is an 8-bit working register used for ALU operations. It is not an addressable register.
Depending on the instruction executed, the ALU may affect the values of the Carry (C), Digit Carry (DC), and Zero (Z) bits in the STATUS register. The C and DC bits operate as a borr
ow and digit borrow out bit, respectively, in subtraction. See the SUBWF and ADDWF instructions for examples.
A simplified block diagram is shown in Figure 3-1, with the corresponding device pins described in Table 3-1.
PIC12C5XX
DS40139D-page 10
1998 Microchip Technology Inc.
FIGURE 3-1: PIC12C5XX BLOCK DIAGRAM
Device Reset
Timer
Power-on
Reset
Watchdog
Timer
EPROM
Program
Memory
12
Data Bus
8
12
Program
Bus
Instruction reg
Program Counter
RAM
File
Registers
Direct Addr
5
RAM Addr
9
Addr MUX
Indirect
Addr
FSR reg
STATUS reg
MUX
ALU
W reg
Instruction
Decode &
Control
Timing
Generation
OSC1/CLKIN
OSC2
MCLR
Vdd, Vss
Timer0
GPIO
8
8
GP4/OSC2
GP3/MCLR/Vpp
GP2/T0CKI
GP1
GP0
5-7
3
GP5/OSC1/CLKIN
STACK1 STACK2
512 x 12 or
25 x 8 or
1024 x 12
41 x 8
Internal RC
OSC
1998 Microchip Technology Inc. DS40139D-page 11
PIC12C5XX
TABLE 3-1: PIC12C5XX PINOUT DESCRIPTION
Name
DIP
Pin #
SOIC Pin #
I/O/P Type
Buffer
Type
Description
GP0 7 7 I/O TTL/ST Bi-directional I/O port/ serial programming data. Can
be software programmed for internal weak pull-up and wake-up from SLEEP on pin change. This buffer is a Schmitt Trigger input when used in serial programming mode.
GP1 6 6 I/O TTL/ST Bi-directional I/O port/ serial programming clock. Can
be software programmed for internal weak pull-up and wake-up from SLEEP on pin change. This buffer is a Schmitt Trigger input when used in serial programming
mode. GP2/T0CKI 5 5 I/O ST Bi-directional I/O port. Can be configured as T0CKI. GP3/MCLR
/V
PP
4 4 I TTL/ST Input port/master clear (reset) input/programming volt-
age input. When configured as MCLR
, this pin is an
active low reset to the device. Voltage on MCLR
/V
PP
must not exceed V
DD
during normal device operation or the device will enter programming mode. Can be software programmed for internal weak pull-up and wake-up from SLEEP on pin change. Weak pull-up always on if configured as MCLR
. ST when in MCLR
mode.
GP4/OSC2 3 3 I/O TTL Bi-directional I/O port/oscillator crystal output. Con-
nections to crystal or resonator in crystal oscillator mode (XT and LP modes only, GPIO in other modes).
GP5/OSC1/CLKIN 2 2 I/O TTL/ST Bidirectional IO port/oscillator crystal input/external
clock source input (GPIO in Internal RC mode only, OSC1 in all other oscillator modes). TTL input when GPIO, ST input in external RC oscillator mode.
V
DD
1 1 P Positive supply for logic and I/O pins
V
SS
8 8 P Ground reference for logic and I/O pins
Legend: I = input, O = output, I/O = input/output, P = power, — = not used, TTL = TTL input, ST = Schmitt Trigger input
PIC12C5XX
DS40139D-page 12
1998 Microchip Technology Inc.
3.1 Cloc
king Scheme/Instruction Cycle
The clock input (OSC1/CLKIN pin) is internally divided by four to generate four non-overlapping quadrature clocks namely Q1, Q2, Q3 and Q4. Internally, the program counter is incremented every Q1, and the instruction is fetched from program memory and latched into instruction register in Q4. It is decoded and executed during the following Q1 through Q4. The clocks and instruction execution flow is shown in Figure 3-2 and Example 3-1.
3.2 Instruction Flo
w/Pipelining
An Instruction Cycle consists of four Q cycles (Q1, Q2, Q3 and Q4). The instruction fetch and execute are pipelined such that fetch takes one instruction cycle while decode and execute takes another instruction cycle. However, due to the pipelining, each instruction effectively executes in one cycle. If an instruction causes the program counter to change (e.g., GOTO ) then two cycles are required to complete the instruction (Example 3-1).
A fetch cycle begins with the program counter (PC) incrementing in Q1.
In the execution cycle, the fetched instruction is latched into the Instruction Register (IR) in cycle Q1. This instruction is then decoded and executed during the Q2, Q3, and Q4 cycles. Data memory is read during Q2 (operand read) and written during Q4 (destination write).
FIGURE 3-2: CLOCK/INSTRUCTION CYCLE
EXAMPLE 3-1: INSTRUCTION PIPELINE FLOW
Q1
Q2 Q3 Q4
Q1
Q2 Q3 Q4
Q1
Q2 Q3 Q4
OSC1
Q1 Q2 Q3 Q4 PC
PC PC+1 PC+2
Fetch INST (PC)
Execute INST (PC-1) Fetch INST (PC+1)
Execute INST (PC) Fetch INST (PC+2)
Execute INST (PC+1)
Internal
phase clock
All instructions are single cycle, except for any program branches. These take two cycles since the fetch instruction is “flushed” from the pipeline while the new instruction is being fetched and then executed.
1. MOVLW 03H
Fetch 1 Execute 1
2. MOVWF GPIO
Fetch 2 Execute 2
3. CALL SUB_1
Fetch 3 Execute 3
4. BSF GPIO, BIT1
Fetch 4 Flush
Fetch SUB_1 Execute SUB_1
1998 Microchip Technology Inc. DS40139D-page 13
PIC12C5XX
4.0 MEMORY ORGANIZATION
PIC12C5XX memory is organized into program mem­ory and data memory. For devices with more than 512 bytes of program memory, a paging scheme is used. Program memory pages are accessed using one STA­TUS register bit. For the PIC12C509(A) with a data memory register file of more than 32 registers, a bank­ing scheme is used. Data memory banks are accessed using the File Select Register (FSR).
4.1 Pr
ogram Memory Organization
The PIC12C5XX devices have a 12-bit Program Counter (PC) capable of addressing a 2K x 12 program memory space.
Only the first 512 x 12 (0000h-01FFh) for the PIC12C508(A) and 1K x 12 (0000h-03FFh) for the PIC12C509(A) are physically implemented. Refer to Figure 4-1. Accessing a location above these boundaries will cause a wrap-around within the first 512 x 12 space (PIC12C508(A)) or 1K x 12 space (PIC12C509(A)). The effective reset vector is at 000h, (see Figure 4-1). Location 01FFh (PIC12C508(A)) or location 03FFh (PIC12C509(A)) contains the internal clock oscillator calibration value. This value should never be overwritten.
FIGURE 4-1: PROGRAM MEMORY MAP
AND STACK FOR THE PIC12C5XX
CALL, RETLW
PC<11:0>
Stack Level 1 Stack Level 2
User Memory
Space
12
0000h
7FFh
01FFh 0200h
On-chip Program
Memory
Reset Vector (note 1)
Note 1: Address 0000h becomes the
effective reset vector. Location 01FFh (PIC12C508(A)) or location 03FFh (PIC12C509(A)) contains the MOVLW XX INTERNAL RC oscil- lator calibration value.
512 Word (PIC12C508(A))
1024 Word (PIC12C509(A))
03FFh 0400h
On-chip Program
Memory
PIC12C5XX
DS40139D-page 14
1998 Microchip Technology Inc.
4.2 Data Memor
y Organization
Data memory is composed of registers, or bytes of RAM. Therefore, data memory for a device is specified by its register file. The register file is divided into two functional groups: special function registers and general purpose registers.
The special function registers include the TMR0 register, the Program Counter (PC), the Status Register, the I/O registers (ports), and the File Select Register (FSR). In addition, special purpose registers are used to control the I/O port configuration and prescaler options.
The general purpose registers are used for data and control information under command of the instructions.
For the PIC12C508(A), the register file is composed of 7 special function registers and 25 general purpose registers (Figure 4-2).
For the PIC12C509(A), the register file is composed of 7 special function registers, 25 general purpose registers, and 16 general purpose registers that may be addressed using a banking scheme (Figure 4-3).
4.2.1 GENERAL PURPOSE REGISTER FILE The general purpose register file is accessed either
directly or indirectly through the file select register FSR (Section 4.8).
FIGURE 4-2: PIC12C508(A) REGISTER FILE
MAP
File Address
00h 01h 02h 03h 04h 05h 06h 07h
1Fh
INDF
(1)
TMR0
PCL
STATUS
FSR
OSCCAL
GPIO
General
Purpose
Registers
Note 1: Not a physical register. See Section 4.8
FIGURE 4-3: PIC12C509(A) REGISTER FILE MAP
File Address
00h 01h 02h 03h 04h 05h 06h
07h
1Fh
INDF
(1)
TMR0
PCL
STATUS
FSR
OSCCAL
GPIO
0Fh
10h
Bank 0 Bank 1
3Fh
30h
20h
2Fh
General Purpose Registers
General Purpose Registers
General Purpose Registers
Addresses map back to addresses in Bank 0.
Note 1: Not a physical register. See Section 4.8
FSR<6:5> 00 01
1998 Microchip Technology Inc. DS40139D-page 15
PIC12C5XX
4.2.2 SPECIAL FUNCTION REGISTERS The Special Function Registers (SFRs) are registers
used by the CPU and peripheral functions to control the operation of the device (Table 4-1).
The special registers can be classified into two sets. The special function registers associated with the “core” functions are described in this section. Those related to the operation of the peripheral features are described in the section for each peripheral feature.
TABLE 4-1: SPECIAL FUNCTION REGISTER (SFR) SUMMARY
Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Value on
Power-On
Reset
Value on All Other
Resets
(2)
N/A TRIS I/O control registers
--11 1111 --11 1111
N/A OPTION
Contains control bits to configure Timer0, Timer0/WDT prescaler, wake-up on change, and weak pull-ups
1111 1111 1111 1111
00h INDF Uses contents of FSR to address data memory (not a physical register)
xxxx xxxx uuuu uuuu
01h TMR0 8-bit real-time clock/counter
xxxx xxxx uuuu uuuu
02h
(1)
PCL Low order 8 bits of PC
1111 1111 1111 1111
03h STATUS GPWUF PA0 TO PD Z DC C
0001 1xxx q00q quuu
(3)
04h
FSR (12C508/ 12C508A)
Indirect data memory address pointer
111x xxxx 111u uuuu
04h
FSR (12C509/ 12C509A)
Indirect data memory address pointer
110x xxxx 11uu uuuu
05h
OSCCAL (12C508/ 12C509) CAL3 CAL2 CAL1 CAL0
0111 ---- uuuu ----
05h
OSCCAL (12C508A/ 12C509A)
CAL5 CAL4 CAL3 CAL2 CAL1 CAL0
1000 00-- uuuu uu--
06h GPIO GP5 GP4 GP3 GP2 GP1 GP0
--xx xxxx --uu uuuu
Legend: Shaded boxes = unimplemented or unused, = unimplemented, read as '0' (if applicable)
x = unknown, u = unchanged, q = see the tables in Section 7.7 for possible values.
Note 1: The upper byte of the Program Counter is not directly accessible. See Section 4.6
for an explanation of how to access these bits. 2: Other (non power-up) resets include external reset through MCLR, watchdog timer and wake-up on pin change reset. 3: If reset was due to wake-up on pin change then bit 7 = 1. All other resets will cause bit 7 = 0.
PIC12C5XX
DS40139D-page 16 1998 Microchip Technology Inc.
4.3 STATUS Register
This register contains the arithmetic status of the ALU, the RESET status, and the page preselect bit for program memories larger than 512 words.
The STATUS register can be the destination for any instruction, as with any other register. If the STATUS register is the destination for an instruction that affects the Z, DC or C bits, then the write to these three bits is disabled. These bits are set or cleared according to the device logic. Furthermore, the T
O and PD bits are not writable. Therefore, the result of an instruction with the STATUS register as destination may be different than intended.
For example, CLRF STATUS will clear the upper three bits and set the Z bit. This leaves the STATUS register as 000u u1uu (where u = unchanged).
It is recommended, therefore, that only BCF, BSF and MOVWF instructions be used to alter the STATUS register because these instructions do not affect the Z, DC or C bits from the STATUS register. For other instructions, which do affect STATUS bits, see Instruction Set Summary.
FIGURE 4-4: STATUS REGISTER (ADDRESS:03h)
R/W-0 R/W-0 R/W-0 R-1 R-1 R/W-x R/W-x R/W-x
GPWUF
PA0 TO PD Z DC C R = Readable bit
W = Writable bit
- n = Value at POR reset
bit7 6 5 4 3 2 1 bit0 bit 7: GPWUF: GPIO reset bit
1 = Reset due to wake-up from SLEEP on pin change
0 = After power up or other reset bit 6: Unimplemented bit 5: PA0: Program page preselect bits
1 = Page 1 (200h - 3FFh) - PIC12C509(A)
0 = Page 0 (000h - 1FFh) - PIC12C508(A) and PIC12C509(A)
Each page is 512 bytes.
Using the PA0 bit as a general purpose read/write bit in devices which do not use it for program
page preselect is not recommended since this may affect upward compatibility with future products. bit 4: TO: Time-out bit
1 = After power-up, CLRWDT instruction, or SLEEP instruction
0 = A WDT time-out occurred bit 3: PD: Power-down bit
1 = After power-up or by the CLRWDT instruction
0 = By execution of the SLEEP instruction bit 2: Z: Zero bit
1 = The result of an arithmetic or logic operation is zero
0 = The result of an arithmetic or logic operation is not zero bit 1: DC: Digit carry/borrow bit (for ADDWF and SUBWF instructions)
ADDWF
1 = A carry from the 4th low order bit of the result occurred
0 = A carry from the 4th low order bit of the result did not occur
SUBWF
1 = A borrow from the 4th low order bit of the result did not occur
0 = A borrow from the 4th low order bit of the result occurred bit 0: C: Carry/borrow bit (for ADDWF, SUBWF and RRF, RLF instructions)
ADDWF SUBWF RRF or RLF
1 = A carry occurred 1 = A borrow did not occur Load bit with LSB or MSB, respectively
0 = A carry did not occur 0 = A borrow occurred
1998 Microchip Technology Inc. DS40139D-page 17
PIC12C5XX
4.4 OPTION Register
The OPTION register is a 8-bit wide, write-only register which contains various control bits to configure the Timer0/WDT prescaler and Timer0.
By executing the OPTION instruction, the contents of the W register will be transferred to the OPTION register. A RESET sets the OPTION<7:0> bits.
Note: If TRIS bit is set to ‘0’, the wake-up on
change and pull-up functions are disabled for that pin; i.e., note that TRIS overr ides OPTION control of GPPU
and GPWU.
Note: If the T0CS bit is set to ‘1’, GP2 is f orced to
be an input even if TRIS GP2 = ‘0’.
FIGURE 4-5: OPTION REGISTER
W-1 W-1 W-1 W-1 W-1 W-1 W-1 W-1
GPWU GPPU T0CS T0SE PSA PS2 PS1 PS0 W = Writable bit
U = Unimplemented bit
- n = Value at POR reset Reference Table 4-1 for other resets.
bit7 6 5 4 3 2 1 bit0
bit 7: GPWU
: Enable wake-up on pin change (GP0, GP1, GP3) 1 = Disabled 0 = Enabled
bit 6: GPPU: Enable weak pull-ups (GP0, GP1, GP3)
1 = Disabled 0 = Enabled
bit 5: T0CS: Timer0 clock source select bit
1 = Transition on T0CKI pin 0 = Transition on internal instruction cycle clock, Fosc/4
bit 4: T0SE: Timer0 source edge select bit
1 = Increment on high to low transition on the T0CKI pin 0 = Increment on low to high transition on the T0CKI pin
bit 3: PSA: Prescaler assignment bit
1 = Prescaler assigned to the WDT 0 = Prescaler assigned to Timer0
bit 2-0: PS2:PS0: Prescaler rate select bits
000 001 010 011 100 101 110 111
1 : 2 1 : 4 1 : 8 1 : 16 1 : 32 1 : 64 1 : 128 1 : 256
1 : 1 1 : 2 1 : 4 1 : 8 1 : 16 1 : 32 1 : 64 1 : 128
Bit Value Timer0 Rate WDT Rate
PIC12C5XX
DS40139D-page 18 1998 Microchip Technology Inc.
4.5 OSCCAL Register
The Oscillator Calibration (OSCCAL) register is used to calibrate the internal 4 MHz oscillator. It contains four to six bits for calibration. Increasing the cal value increases the frequency. See Section 7.2.5 for more information on the internal oscillator.
FIGURE 4-6: OSCCAL REGISTER (ADDRESS 8Fh)
FIGURE 4-7: OSCCAL REGISTER (ADDRESS 8Fh)PIC12C508A/C509A
R/W-0 R/W-1 R/W-1 R/W-1 R/W-0 R/W-0 U-0 U-0
CAL3 CAL2 CAL1 CAL0 R = Readable bit
W = Writable bit U = Unimplemented bit,
read as ‘0’
- n = Value at POR reset
bit7 bit0
bit 7-4: CAL<3:0>: Calibration bit 3-0: Unimplemented: Read as '0'
R/W-1 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 U-0 U-0
CAL5 CAL4 CAL3 CAL2 CAL1 CAL0 R = Readable bit
W = Writable bit U = Unimplemented bit,
read as ‘0’
- n = Value at POR reset
bit7 bit0
bit 7-2: CAL<5:0>: Calibration bit 1-0: Unimplemented: Read as '0'
1998 Microchip Technology Inc. DS40139D-page 19
PIC12C5XX
4.6 Program Counter
As a program instruction is executed, the Program Counter (PC) will contain the address of the next program instruction to be executed. The PC value is increased by one every instruction cycle, unless an instruction changes the PC.
For a GOTO instruction, bits 8:0 of the PC are provided by the GOTO instruction word. The PC Latch (PCL) is mapped to PC<7:0>. Bit 5 of the STATUS register provides page information to bit 9 of the PC (Figure 4-
8). For a CALL instruction, or any instruction where the
PCL is the destination, bits 7:0 of the PC again are provided by the instruction word. However, PC<8> does not come from the instruction word, but is always cleared (Figure 4-8).
Instructions where the PCL is the destination, or Modify PCL instructions, include MOVWF PC, ADDWF PC, and BSF PC,5.
FIGURE 4-8: LOADING OF PC
BRANCH INSTRUCTIONS -
PIC12C5XX
Note: Because PC<8> is cleared in the CALL
instruction, or any Modify PCL instruction, all subroutine calls or computed jumps are limited to the first 256 locations of any pro­gram memory page (512 words long).
PA0
STATUS
PC
8 7 0
PCL
910
Instruction Word
7 0
GOTO Instruction
CALL or Modify PCL Instruction
11
PA0
STATUS
PC
8 7 0
PCL
910
Instruction Word
7 0
11
Reset to ‘0’
4.6.1 EFFECTS OF RESET The Program Counter is set upon a RESET, which
means that the PC addresses the last location in the last page i.e., the oscillator calibration instruction. After executing MOVLW XX, the PC will roll over to location 00h, and begin executing user code.
The STATUS register page preselect bits are cleared upon a RESET, which means that page 0 is pre­selected.
Therefore, upon a RESET, a GOTO instruction will automatically cause the program to jump to page 0 until the value of the page bits is altered.
4.7 Stack
PIC12C5XX devices have a 12-bit wide L.I.F.O. hardware push/pop stack.
A CALL instruction will
push
the current value of stack 1 into stack 2 and then push the current program counter value, incremented by one , into stac k le v el 1. If more than two sequential CALL’s are executed, only the most recent two return addresses are stored.
A RETLW instruction will
pop
the contents of stack level 1 into the program counter and then copy stack level 2 contents into level 1. If more than two sequential RETLW’s are executed, the stack will be filled with the address previously stored in level 2. Note that the W register will be loaded with the literal value specified in the instruction. This is particularly useful for the implementation of data look-up tables within the program memory.
Upon any reset, the contents of the stack remain unchanged, however the program counter (PCL) will also be reset to 0.
Note 1: There are no STATUS bits to indicate
stack overflows or stack underflow condi­tions.
Note 2: There are no instructions mnemonics
called PUSH or POP. These are actions that occur from the execution of the CALL and RETLW instructions.
PIC12C5XX
DS40139D-page 20 1998 Microchip Technology Inc.
4.8 Indirect Data Addressing; INDF and FSR Registers
The INDF register is not a physical register. Addressing INDF actually addresses the register whose address is contained in the FSR register (FSR is a
pointer
). This is indirect addressing.
EXAMPLE 4-1: INDIRECT ADDRESSING
• Register file 07 contains the value 10h
• Register file 08 contains the value 0Ah
• Load the value 07 into the FSR register
• A read of the INDF register will return the value
of 10h
• Increment the value of the FSR register by one
(FSR = 08)
• A read of the INDR register now will return the
value of 0Ah.
Reading INDF itself indirectly (FSR = 0) will produce 00h. Writing to the INDF register indirectly results in a no-operation (although STATUS bits may be affected).
A simple program to clear RAM locations 10h-1Fh using indirect addressing is shown in Example 4-2.
EXAMPLE 4-2: HOW TO CLEAR RAM
USING INDIRECT ADDRESSING
movlw 0x10 ;initialize pointer movwf FSR ; to RAM
NEXT clrf INDF ;clear INDF register
incf FSR,F ;inc pointer btfsc FSR,4 ;all done? goto NEXT ;NO, clear next
CONTINUE
: ;YES, continue
The FSR is a 5-bit wide register. It is used in conjunction with the INDF register to indirectly address the data memory area.
The FSR<4:0> bits are used to select data memory addresses 00h to 1Fh.
PIC12C508(A): Does not use banking. FSR<7:5> are unimplemented and read as '1's.
PIC12C509(A): Uses FSR<5>. Selects between bank 0 and bank 1. FSR<7:6> is unimplemented, read as '1’ .
FIGURE 4-9: DIRECT/INDIRECT ADDRESSING
Note 1: For register map detail see Section 4.2. Note 2: PIC12C509(A) only
bank
location select
location select
bank select
Indirect Addressing
Direct Addressing
Data Memory
(1)
0Fh 10h
Bank 0 Bank 1
(2)
0
4
5
6
(FSR)
00 01
00h
1Fh 3Fh
(opcode) 04
5
6
(FSR)
Addresses map back to addresses in Bank 0.
1998 Microchip Technology Inc. DS40139D-page 21
PIC12C5XX
5.0 I/O PORT
As with any other register, the I/O register can be written and read under program control. However, read instructions (e.g., MOVF GPIO,W) always read the I/O pins independent of the pin’s input/output modes. On RESET, all I/O por ts are defined as input (inputs are at hi-impedance) since the I/O control registers are all set.
5.1 GPIO
GPIO is an 8-bit I/O register. Only the low order 6 bits are used (GP5:GP0). Bits 7 and 6 are unimplemented and read as '0's. Please note that GP3 is an input only pin. The configuration word can set several I/O’s to alternate functions. When acting as alternate functions the pins will read as ‘0’ during por t read. Pins GP0, GP1, and GP3 can be configured with weak pull-ups and also with wake-up on change. The wake-up on change and weak pull-up functions are not pin selectable. If pin 4 is configured as MCLR
, weak pull­up is always on and wake-up on change for this pin is not enabled.
5.2 TRIS Register
The output driver control register is loaded with the contents of the W register by executing the TRIS f instruction. A '1' from a TRIS register bit puts the corresponding output driver in a hi-impedance mode. A '0' puts the contents of the output data latch on the selected pins, enabling the output buffer. The exceptions are GP3 which is input only and GP2 which may be controlled by the option register, see Figure 4-
5.
The TRIS registers are “write-only” and are set (output drivers disabled) upon RESET.
Note: A read of the por ts reads the pins, not the
output data latches. That is, if an output driver on a pin is enabled and driven high, but the external system is holding it low, a read of the port will indicate that the pin is low.
5.3 I/O Interfacing
The equivalent circuit for an I/O port pin is shown in Figure 5-1. All port pins, except GP3 which is input only, may be used for both input and output operations. For input operations these ports are non­latching. Any input must be present until read by an input instruction (e.g., MOVF GPIO,W). The outputs are latched and remain unchanged until the output latch is rewritten. To use a port pin as output, the corresponding direction control bit in TRIS must be cleared (= 0). For use as an input, the corresponding TRIS bit must be set. Any I/O pin (except GP3) can be programmed individually as input or output.
FIGURE 5-1: EQUIVALENT CIRCUIT
FOR A SINGLE I/O PIN
Note 1: I/O pins have protection diodes to VDD and VSS.
Data Bus
QD
Q
CK
QD
Q
CK
P
N
WR Port
TRIS ‘f’
Data
TRIS
RD Port
VSS
VDD
I/O pin
(1)
W Reg
Latch
Latch
Reset
2: See Table 3-1 for buffer type.
(2)
TABLE 5-1: SUMMARY OF PORT REGISTERS
Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Value on
Power-On
Reset
Value on
All Other Resets
N/A TRIS I/O control registers --11 1111 --11 1111 N/A
OPTION GPWU GPPU T0CS T0SE PSA PS2 PS1 PS0
1111 1111 1111 1111
03H
STATUS
GPWUF PAO TO PD Z DC C 0001 1xxx q00q quuu
(1)
06h
GPIO
GP5 GP4 GP3 GP2 GP1 GP0 --xx xxxx --uu uuuu
Legend: Shaded cells not used by Port Registers, read as ‘0’, — = unimplemented, read as '0', x = unknown, u = unchanged,
q = see tables in Section 7.7 for possible values.
Note 1: If reset was due to wake-up on change, then bit 7 = 1. All other resets will cause bit 7 = 0.
PIC12C5XX
DS40139D-page 22 1998 Microchip Technology Inc.
5.4 I/O Programming Considerations
5.4.1 BI-DIRECTIONAL I/O PORTS Some instructions operate internally as read followed
by write operations. The BCF and BSF instructions, for example, read the entire port into the CPU, execute the bit operation and re-write the result. Caution must be used when these instructions are applied to a port where one or more pins are used as input/outputs. For example, a BSF operation on bit5 of GPIO will cause all eight bits of GPIO to be read into the CPU, bit5 to be set and the GPIO value to be written to the output latches. If another bit of GPIO is used as a bi­directional I/O pin (say bit0) and it is defined as an input at this time, the input signal present on the pin itself would be read into the CPU and rewritten to the data latch of this particular pin, overwriting the previous content. As long as the pin stays in the input mode, no problem occurs. However, if bit0 is switched into output mode later on, the content of the data latch may now be unknown.
Example 5-1 shows the effect of two sequential read­modify-write instructions (e.g., BCF, BSF , etc.) on an I/ O port.
A pin actively outputting a high or a low should not be driven from external devices at the same time in order to change the level on this pin (“wired-or”, “wired-and”). The resulting high output currents may damage the chip.
EXAMPLE 5-1: READ-MODIFY-WRITE
INSTRUCTIONS ON AN I/O PORT
;Initial GPIO Settings ; GPIO<5:3> Inputs ; GPIO<2:0> Outputs ; ; GPIO latch GPIO pins ; ---------- ---------­ BCF GPIO, 5 ;--01 -ppp --11 pppp BCF GPIO, 4 ;--10 -ppp --11 pppp MOVLW 007h ; TRIS GPIO ;--10 -ppp --11 pppp ; ;Note that the user may have expected the pin ;values to be --00 pppp. The 2nd BCF caused ;GP5 to be latched as the pin value (High).
5.4.2 SUCCESSIVE OPERATIONS ON I/O PORTS
The actual write to an I/O port happens at the end of an instruction cycle, whereas for reading, the data must be valid at the beginning of the instruction cycle (Figure 5-2). Therefore, care must be exercised if a write followed by a read operation is carried out on the same I/O port. The sequence of instructions should allow the pin voltage to stabilize (load dependent) before the next instruction, which causes that file to be read into the CPU, is executed. Otherwise, the previous state of that pin may be read into the CPU rather than the new state. When in doubt, it is better to separate these instructions with a NOP or another instruction not accessing this I/O port.
FIGURE 5-2: SUCCESSIVE I/O OPERATION
PC PC + 1 PC + 2
PC + 3
Q1 Q2
Q3
Q4
Q1 Q2
Q3
Q4
Q1 Q2
Q3
Q4
Q1 Q2
Q3
Q4
Instruction
fetched
GP5:GP0
MOVWF GPIO
NOP
Port pin sampled here
NOP
MOVF GPIO,W
Instruction
executed
MOVWF GPIO
(Write to
GPIO)
NOP
MOVF GPIO,W
This example shows a write to GPIO followed by a read from GPIO.
Data setup time = (0.25 TCY – TPD) where: TCY = instruction cycle.
TPD = propagation delay
Therefore, at higher clock frequencies, a write followed by a read may be problematic.
(Read
GPIO)
Port pin written here
1998 Microchip Technology Inc. DS40139D-page 23
PIC12C5XX
6.0 TIMER0 MODULE AND TMR0 REGISTER
The Timer0 module has the following features:
• 8-bit timer/counter register, TMR0
- Readable and writable
• 8-bit software programmable prescaler
• Internal or external clock select
- Edge select for external clock
Figure 6-1 is a simplified block diagram of the Timer0 module.
Timer mode is selected by clearing the T0CS bit (OPTION<5>). In timer mode, the Timer0 module will increment every instruction cycle (without prescaler). If TMR0 register is written, the increment is inhibited for the following two instruction cycles (Figure 6-2 and Figure 6-3). The user can work around this by writing an adjusted value to the TMR0 register.
Counter mode is selected by setting the T0CS bit (OPTION<5>). In this mode, Timer0 will increment either on every rising or falling edge of pin T0CKI. The T0SE bit (OPTION<4>) determines the source edge. Clearing the T0SE bit selects the rising edge. Restrictions on the external clock input are discussed in detail in Section 6.1.
The prescaler may be used by either the Timer0 module or the Watchdog Timer, but not both. The prescaler assignment is controlled in software by the control bit PSA (OPTION<3>). Clearing the PSA bit will assign the prescaler to Timer0. The prescaler is not readable or writable. When the prescaler is assigned to the Timer0 module, prescale v alues of 1:2, 1:4,..., 1:256 are selectable. Section 6.2 details the operation of the prescaler.
A summary of registers associated with the Timer0 module is found in Table 6-1.
FIGURE 6-1: TIMER0 BLOCK DIAGRAM
Note 1: Bits T0CS, T0SE, PSA, PS2, PS1 and PS0 are located in the OPTION register.
2: The prescaler is shared with the Watchdog Timer (Figure 6-5).
0
1
1
0
T0CS
(1)
FOSC/4
Programmable
Prescaler
(2)
Sync with
Internal
Clocks
TMR0 reg
PSout
(2 T
CY delay)
PSout
Data bus
8
PSA
(1)
PS2, PS1, PS0
(1)
3
Sync
T0SE
GP2/T0CKI
Pin
PIC12C5XX
DS40139D-page 24 1998 Microchip Technology Inc.
FIGURE 6-2: TIMER0 TIMING: INTERNAL CLOCK/NO PRESCALE
FIGURE 6-3: TIMER0 TIMING: INTERNAL CLOCK/PRESCALE 1:2
TABLE 6-1: REGISTERS ASSOCIATED WITH TIMER0
Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Value on
Power-On
Reset
Value on All Other
Resets
01h TMR0 Timer0 - 8-bit real-time clock/counter xxxx xxxx uuuu uuuu N/A OPTION
GPWU GPPU T0CS T0SE PSA PS2 PS1 PS0 1111 1111 1111 1111
N/A TRIS
GP5 GP4 GP3 GP2 GP1 GP0
--11 1111 --11 1111
Legend: Shaded cells not used by Timer0,
- = unimplemented, x = unknown, u = unchanged,
PC-1
Q1 Q2 Q3 Q4
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
PC (Program Counter)
Instruction
Fetch
Timer0
PC PC+1 PC+2 PC+3 PC+4 PC+5 PC+6
T0
T0+1 T0+2 NT0 NT0+1 NT0+2
MOVWF TMR0
MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W
Write TMR0 executed
Read TMR0 reads NT0
Read TMR0 reads NT0
Read TMR0 reads NT0
Read TMR0 reads NT0 + 1
Read TMR0 reads NT0 + 2
Instruction Executed
PC-1
Q1 Q2 Q3 Q4
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
PC (Program Counter)
Instruction
Fetch
Timer0
PC PC+1 PC+2 PC+3 PC+4 PC+5 PC+6
T0 NT0+1
MOVWF TMR0
MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W
Write TMR0 executed
Read TMR0 reads NT0
Read TMR0 reads NT0
Read TMR0 reads NT0
Read TMR0 reads NT0
Read TMR0 reads NT0 + 1
T0+1
NT0
Instruction Execute
T0
1998 Microchip Technology Inc. DS40139D-page 25
PIC12C5XX
6.1 Using Timer0 with an External Clock
When an external clock input is used for Timer0, it must meet certain requirements. The external clock requirement is due to internal phase clock (T
OSC)
synchronization. Also, there is a delay in the actual incrementing of Timer0 after synchronization.
6.1.1 EXTERNAL CLOCK SYNCHRONIZATION
When no prescaler is used, the external clock input is the same as the prescaler output. The synchronization of T0CKI with the internal phase clocks is accomplished by sampling the prescaler output on the Q2 and Q4 cycles of the internal phase clocks (Figure 6-4). Therefore, it is necessary for T0CKI to be high for at least 2T
OSC (and a small RC delay of 20 ns)
and low for at least 2T
OSC (and a small RC delay of
20 ns). Refer to the electrical specification of the desired device.
When a prescaler is used, the external clock input is divided by the asynchronous ripple counter-type prescaler so that the prescaler output is symmetrical. For the external clock to meet the sampling requirement, the ripple counter must be taken into account. Therefore, it is necessary for T0CKI to have a period of at least 4T
OSC (and a small RC delay of
40 ns) divided by the prescaler value. The only requirement on T0CKI high and low time is that they do not violate the minimum pulse width requirement of 10 ns. Refer to parameters 40, 41 and 42 in the electrical specification of the desired device.
6.1.2 TIMER0 INCREMENT DELAY Since the prescaler output is synchronized with the
internal clocks, there is a small delay from the time the external clock edge occurs to the time the Timer0 module is actually incremented. Figure 6-4 shows the delay from the external clock edge to the timer incrementing.
6.1.3 OPTION REGISTER EFFECT ON GP2 TRIS If the option register is set to read TIMER0 from the pin,
the port is forced to an input regardless of the TRIS reg­ister setting.
FIGURE 6-4: TIMER0 TIMING WITH EXTERNAL CLOCK
Increment Timer0 (Q4)
External Clock Input or
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
Timer0
T0 T0 + 1 T0 + 2
Small pulse misses sampling
External Clock/Prescaler Output After Sampling
(3)
Note 1:
2: 3:
Delay from clock input change to Timer0 increment is 3Tosc to 7Tosc. (Duration of Q = Tosc). Therefore, the error in measuring the interval between two edges on Timer0 input = ± 4Tosc max. External clock if no prescaler selected, Prescaler output otherwise. The arrows indicate the points in time where sampling occurs.
Prescaler Output (2)
(1)
PIC12C5XX
DS40139D-page 26 1998 Microchip Technology Inc.
6.2 Prescaler
An 8-bit counter is available as a prescaler for the Timer0 module, or as a postscaler for the Watchdog Timer (WDT), respectively (Section 7.6). For simplicity, this counter is being referred to as “prescaler” throughout this data sheet. Note that the prescaler may be used by either the Timer0 module or the WDT, but not both. Thus, a prescaler assignment for the Timer0 module means that there is no prescaler for the WDT, and vice-versa.
The PSA and PS2:PS0 bits (OPTION<3:0>) determine prescaler assignment and prescale ratio.
When assigned to the Timer0 module, all instructions writing to the TMR0 register (e.g., CLRF 1, MOVWF 1, BSF 1,x, etc.) will clear the prescaler. When assigned to WDT, a CLRWDT instruction will clear the prescaler along with the WDT. The prescaler is neither readable nor writable. On a RESET, the prescaler contains all '0's.
6.2.1 SWITCHING PRESCALER ASSIGNMENT The prescaler assignment is fully under software control
(i.e., it can be changed “on the fly” during program execution). To avoid an unintended device RESET, the following instruction sequence (Example 6-1) must be executed when changing the prescaler assignment from Timer0 to the WDT.
EXAMPLE 6-1: CHANGING PRESCALER
(TIMER0WDT)
1.CLRWDT ;Clear WDT
2.CLRF TMR0 ;Clear TMR0 & Prescaler
3.MOVLW '00xx1111’b ;These 3 lines (5, 6, 7)
4.OPTION ; are required only if ; desired
5.CLRWDT ;PS<2:0> are 000 or 001
6.MOVLW '00xx1xxx’b ;Set Postscaler to
7.OPTION ; desired WDT rate
To change prescaler from the WDT to the Timer0 module, use the sequence shown in Example 6-2. This sequence must be used even if the WDT is disabled. A CLRWDT instruction should be executed before switching the prescaler.
EXAMPLE 6-2: CHANGING PRESCALER
(WDTTIMER0)
CLRWDT ;Clear WDT and
;prescaler
MOVLW 'xxxx0xxx' ;Select TMR0, new
;prescale value and ;clock source
OPTION
FIGURE 6-5: BLOCK DIAGRAM OF THE TIMER0/WDT PRESCALER
TCY ( = Fosc/4)
Sync
2
Cycles
TMR0 reg
8-bit Prescaler
8 - to - 1MUX
M
MUX
Watchdog
Timer
PSA
0
1
0
1
WDT
Time-Out
PS2:PS0
8
Note: T0CS, T0SE, PSA, PS2:PS0 are bits in the OPTION register.
PSA
WDT Enable bit
0
1
0
1
Data Bus
8
PSA
T0CS
M U
X
M U
X
U X
T0SE
GP2/T0CKI
Pin
1998 Microchip Technology Inc. DS40139D-page 27
PIC12C5XX
7.0 SPECIAL FEATURES OF THE CPU
What sets a microcontroller apart from other processors are special circuits to deal with the needs of real-time applications. The PIC12C5XX family of microcontrollers has a host of such features intended to maximize system reliability, minimize cost through elimination of external components, provide power saving operating modes and offer code protection. These features are:
• Oscillator selection
• Reset
- Power-On Reset (POR)
- Device Reset Timer (DRT)
- Wake-up from SLEEP on pin change
• Watchdog Timer (WDT)
• SLEEP
• Code protection
• ID locations
• In-circuit Serial Programming
The PIC12C5XX has a Watchdog Timer which can be shut off only through configuration bit WDTE. It r uns off of its own RC oscillator for added reliability. If using XT or LP selectable oscillator options, there is always an 18 ms (nominal) delay provided by the Device Reset Timer (DRT), intended to keep the chip in reset until the crystal oscillator is stable. If using INTRC or EXTRC there is an 18 ms delay only on V
DD power-up.
With this timer on-chip, most applications need no external reset circuitry.
The SLEEP mode is designed to offer a very low current power-down mode. The user can wake-up from SLEEP through a change on input pins or through a Watchdog Timer time-out. Several oscillator options are also made available to allow the part to fit the application, including an internal 4 MHz oscillator. The EXTRC oscillator option saves system cost while the LP crystal option saves power. A set of configuration bits are used to select various options.
7.1 Configuration Bits
The PIC12C5XX configuration word consists of 12 bits. Configuration bits can be programmed to select various device configurations. Two bits are for the selection of the oscillator type, one bit is the Watchdog Timer enable bit, and one bit is the MCLR
enable bit.
FIGURE 7-1: CONFIGURATION WORD FOR PIC12C5XX
MCLRE CP WDTE FOSC1 FOSC0 Register: CONFIG
Address
(1)
: FFFh
bit11 10 9 8 7 6 5 4 3 2 1 bit0 bit 11-5: Unimplemented bit 4: MCLRE: MCLR
enable bit. 1 = MCLR pin enabled 0 = MCLR tied to VDD, (Internally)
bit 3: CP: Code protection bit.
1 = Code protection off 0 = Code protection on
bit 2: WDTE: Watchdog timer enable bit
1 = WDT enabled 0 = WDT disabled
bit 1-0: FOSC1:FOSC0: Oscillator selection bits
11 = EXTRC - external RC oscillator 10 = INTRC - internal RC oscillator 01 = XT oscillator 00 = LP oscillator
Note 1: Refer to the PIC12C5XX Programming Specifications to determine how to access the
configuration word. This register is not user addressable during device operation.
PIC12C5XX
DS40139D-page 28 1998 Microchip Technology Inc.
7.2 Oscillator Configurations
7.2.1 OSCILLATOR TYPES The PIC12C5XX can be operated in four different
oscillator modes. The user can program two configuration bits (FOSC1:FOSC0) to select one of these four modes:
• LP: Low Power Crystal
• XT: Crystal/Resonator
• INTRC: Internal 4 MHz Oscillator
• EXTRC: External Resistor/Capacitor
7.2.2 CRYSTAL OSCILLATOR / CERAMIC RESONATORS
In XT or LP modes, a crystal or ceramic resonator is connected to the GP5/OSC1/CLKIN and GP4/OSC2 pins to establish oscillation (Figure 7-2). The PIC12C5XX oscillator design requires the use of a parallel cut crystal. Use of a series cut crystal may give a frequency out of the crystal manufacturers specifications. When in XT or LP modes, the device can have an external clock source drive the GP5/ OSC1/CLKIN pin (Figure 7-3).
FIGURE 7-2: CRYSTAL OPERATION (OR
CERAMIC RESONATOR) (XT OR LP OSC CONFIGURATION)
FIGURE 7-3: EXTERNAL CLOCK INPUT
OPERATION (XT OR LP OSC CONFIGURATION)
Note 1: See Capacitor Selection tables for
recommended values of C1 and C2.
2: A series resistor (RS) may be required for
AT strip cut crystals.
3: RF approximate value = 10 MΩ.
C1
(1)
C2
(1)
XTAL
OSC2
OSC1
RF
(3)
SLEEP
To internal
logic
RS
(2)
PIC12C5XX
Clock from ext. system
OSC1
OSC2
Open
PIC12C5XX
TABLE 7-1: CAPACITOR SELECTION
FOR CERAMIC RESONATORS
- PIC12C5XX
T ABLE 7-2: CAPACITOR SELECTION
FOR CRYSTAL OSCILLATOR
- PIC12C5XX
Osc
Type
Resonator
Freq
Cap. RangeC1Cap. Range
C2
XT 4.0 MHz 30 pF 30 pF
These values are for design guidance only. Since each resonator has its own characteristics, the user should consult the resonator manufacturer for appropriate values of external components.
Osc
Type
Resonator
Freq
Cap.Range
C1
Cap. Range
C2
LP 32 kHz
(1)
15 pF 15 pF
XT 200 kHz
1 MHz 4 MHz
47-68 pF
15 pF 15 pF
47-68 pF
15 pF 15 pF
Note 1: For V
DD > 4.5V, C1 = C2 30 pF is
recommended. These values are for design guidance only. Rs may be required to avoid overdriving crystals with low drive level specification. Since each crystal has its own characteristics, the user should consult the crys­tal manufacturer for appropriate values of external components.
1998 Microchip Technology Inc. DS40139D-page 29
PIC12C5XX
7.2.3 EXTERNAL CRYSTAL OSCILLATOR CIRCUIT
Either a prepackaged oscillator or a simple oscillator circuit with TTL gates can be used as an external crystal oscillator circuit. Prepackaged oscillators provide a wide operating range and better stability. A well-designed crystal oscillator will provide good performance with TTL gates. Two types of crystal oscillator circuits can be used: one with parallel resonance, or one with series resonance.
Figure 7-4 shows implementation of a parallel resonant oscillator circuit. The circuit is designed to use the fundamental frequency of the crystal. The 74AS04 inverter performs the 180-degree phase shift that a parallel oscillator requires. The 4.7 k resistor provides the negative feedback for stability. The 10 k potentiometers bias the 74AS04 in the linear region. This circuit could be used for external oscillator designs.
FIGURE 7-4: EXTERNAL PARALLEL
RESONANT CRYSTAL OSCILLATOR CIRCUIT
Figure 7-5 shows a series resonant oscillator circuit. This circuit is also designed to use the fundamental frequency of the crystal. The inverter performs a 180­degree phase shift in a series resonant oscillator circuit. The 330 Ω resistors provide the negative feedback to bias the inverters in their linear region.
FIGURE 7-5: EXTERNAL SERIES
RESONANT CRYSTAL OSCILLATOR CIRCUIT
20 pF
+5V
20 pF
10k
4.7k
10k
74AS04
XTAL
10k
74AS04
CLKIN
To Other Devices
PIC12C5XX
330
74AS04
74AS04
CLKIN
To Other Devices
XTAL
330
74AS04
0.1 µF
PIC12C5XX
7.2.4 EXTERNAL RC OSCILLATOR For timing insensitive applications, the RC device
option offers additional cost savings. The RC oscillator frequency is a function of the supply voltage, the resistor (Rext) and capacitor (Cext) values, and the operating temperature. In addition to this, the oscillator frequency will vary from unit to unit due to normal process parameter variation. Furthermore, the difference in lead frame capacitance between package types will also affect the oscillation frequency, especially for low Cext values. The user also needs to take into account variation due to tolerance of external R and C components used.
Figure 7-6 shows how the R/C combination is connected to the PIC12C5XX. For Rext values below
2.2 kΩ, the oscillator operation may become unstable, or stop completely. For very high Rext values (e.g., 1 M) the oscillator becomes sensitive to noise, humidity and leakage. Thus, we recommend keeping Rext between 3 k and 100 kΩ.
Although the oscillator will operate with no external capacitor (Cext = 0 pF), we recommend using values above 20 pF for noise and stability reasons. With no or small external capacitance, the oscillation frequency can vary dramatically due to changes in external capacitances, such as PCB trace capacitance or package lead frame capacitance.
The Electrical Specifications sections show RC frequency variation from part to part due to normal process variation. The variation is larger for larger R (since leakage current variation will affect RC frequency more for large R) and for smaller C (since variation of input capacitance will affect RC frequency more).
Also, see the Electrical Specifications sections for variation of oscillator frequency due to V
DD for given
Rext/Cext values as well as frequency variation due to operating temperature for giv en R, C, and V
DD values.
FIGURE 7-6: EXTERNAL RC OSCILLATOR
MODE
VDD
Rext
Cext V
SS
OSC1
Internal clock
N
PIC12C5XX
PIC12C5XX
DS40139D-page 30 1998 Microchip Technology Inc.
7.2.5 INTERNAL 4 MHz RC OSCILLATOR The internal RC oscillator provides a fixed 4 MHz (nom-
inal) system clock at VDD = 5V and 25°C, see “Electri- cal Specifications” section for infor mation on variation over voltage and temperature..
In addition, a calibration instruction is programmed into the top of memory which contains the calibration value for the internal RC oscillator. This location is ne ver code protected regardless of the code protect settings. This value is prog rammed as a MOVLW XX instruction where XX is the calibration value, and is placed at the reset vector. This will load the W register with the calibration value upon reset and the PC will then roll over to the users program at address 0x000. The user then has the option of writing the value to the OSCCAL Register (05h) or ignoring it.
OSCCAL, when written to with the calibration value, will “trim” the internal oscillator to remove process variation from the oscillator frequency. .
For the PIC12C508A and PIC12C509A, bits <7:2>, CAL5-CAL0 are used for calibration. Adjusting CAL5­0 from 000000 to 111111 yields a higher clock speed. Note that bits 1 and 0 of OSCCAL are unimplemented and should be written as 0 when modifying OSCCAL for compatibility with future devices.
For the PIC12C508 and PIC12C509, the lower 4 bits of the register are used. Writing a larger value in this loca­tion yields a higher clock speed.
7.3 RESET
The device differentiates between various kinds of reset:
a) Power on reset (POR) b) MCLR
reset during normal operation
c) MCLR
reset during SLEEP d) WDT time-out reset during normal operation e) WDT time-out reset during SLEEP f) Wake-up from SLEEP on pin change
Some registers are not reset in any way; they are unknown on POR and unchanged in any other reset. Most other registers are reset to “reset state” on po wer­on reset (POR), MCLR
, WDT or wake-up on pin change reset during normal operation. They are not affected by a WDT reset during SLEEP or MCLR
reset during SLEEP, since these resets are viewed as resumption of normal operation. The exceptions to this
Note: Please note that erasing the device will
also erase the pre-programmed internal calibration value for the internal oscillator. The calibration value must be read prior to erasing the part. so it can be repro­grammed correctly later.
are TO, PD, and GPWUF bits. They are set or cleared differently in different reset situations. These bits are used in software to determine the nature of reset. See Table 7-3 for a full description of reset states of all registers.
1998 Microchip Technology Inc. DS40139D-page 31
PIC12C5XX
TABLE 7-3: RESET CONDITIONS FOR REGISTERS
TABLE 7-4: RESET CONDITION FOR SPECIAL REGISTERS
Register Address Power-on Reset
MCLR
Reset
WDT time-out
Wake-up on Pin Change
W (PIC12C508/509)
qqqq xxxx
(1)
qqqq uuuu
(1)
W (PIC12C508A/509A)
qqqq qqxx
(1)
qqqq qquu
(1)
INDF 00h xxxx xxxx uuuu uuuu
TMR0 01h xxxx xxxx uuuu uuuu
PC 02h 1111 1111 1111 1111
STATUS 03h 0001 1xxx
q00q quuu
(2,3)
FSR (12C508/12C508A) 04h 111x xxxx 111u uuuu FSR (12C509/12C509A) 04h 110x xxxx 11uu uuuu
OSCCAL(12C508/509) 05h 0111 ---- uuuu ----
OSCCAL(12C508A/509A) 05h 1000 00-- uuuu uu--
GPIO 06h --xx xxxx --uu uuuu
OPTION 1111 1111 1111 1111
TRIS --11 1111 --11 1111
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’, q = value depends on condition.
Note 1: Bits <7:2> of W register contain oscillator calibration values due to MOVLW XX instruction at top of memory . Note 2: See Table 7-7 for reset value for specific conditions Note 3: If reset was due to wake-up on pin change, then bit 7 = 1. All other resets will cause bit 7 = 0.
STATUS Addr: 03h PCL Addr: 02h
Power on reset 0001 1xxx 1111 1111 MCLR
reset during normal operation 000u uuuu 1111 1111
MCLR
reset during SLEEP 0001 0uuu 1111 1111 WDT reset during SLEEP 0000 0uuu 1111 1111 WDT reset normal operation 0000 uuuu 1111 1111 Wake-up from SLEEP on pin change 1001 0uuu 1111 1111 Legend: u = unchanged, x = unknown, - = unimplemented bit, read as ‘0’.
PIC12C5XX
DS40139D-page 32 1998 Microchip Technology Inc.
7.3.1 MCLR ENABLE This configuration bit when unprogrammed (left in the
‘1’ state) enables the external MCLR
function. When
programmed, the MCLR
function is tied to the internal
V
DD, and the pin is assigned to be a GPIO. See
Figure 7-7. When pin GP3/MCLR
/VPP is configured as
MCLR
, the internal pull-up is always on.
FIGURE 7-7: MCLR SELECT
7.4 P
ower-On Reset (POR)
The PIC12C5XX family incorporates on-chip Power­On Reset (POR) circuitry which provides an internal chip reset for most power-up situations.
The on-chip POR circuit holds the chip in reset until V
DD has reached a high enough level f or proper opera-
tion. To take advantage of the internal POR, program the GP3/MCLR
/VPP pin as MCLR and tie thru a resis-
tor to V
DD or program the pin as GP3. An internal weak
pull-up resistor is implemented using a transistor. Refer to Tab le 10-1 for the pull-up resistor ranges. This will eliminate external RC components usually needed to create a Power-on Reset. A maximum rise time for V
DD
is specified. See Electrical Specifications for details. When the device starts normal operation (exits the
reset condition), device operating parameters (voltage , frequency, temperature, ...) must be met to ensure operation. If these conditions are not met, the device must be held in reset until the operating parameters are met.
A simplified block diagram of the on-chip Power-On Reset circuit is shown in Figure 7-8.
GP3/MCLR/VPP
MCLRE
INTERNAL MCLR
WEAK PULL-UP
The Power-On Reset circuit and the Device Reset Timer (Section 7.5) circuit are closely related. On power-up, the reset latch is set and the DRT is reset. The DRT timer begins counting once it detects MCLR to be high. After the time-out period, which is typically 18 ms, it will reset the reset latch and thus end the on­chip reset signal.
A power-up example where MCLR
is held low is
shown in Figure 7-9. V
DD is allowed to rise and
stabilize before bringing MCLR
high. The chip will
actually come out of reset T
DRT msec after MCLR
goes high. In Figure 7-10, the on-chip Power-On Reset feature is
being used (MCLR
and VDD are tied together or the
pin is programmed to be GP3.). The V
DD is stable
before the start-up timer times out and there is no problem in getting a proper reset. However, Figure 7­11 depicts a problem situation where V
DD rises too
slowly. The time between when the DRT senses that MCLR
is high and when MCLR (and VDD) actually reach their full value, is too long. In this situation, when the start-up timer times out, V
DD has not reached the
V
DD (min) value and the chip is, therefore, not
guaranteed to function correctly. For such situations, we recommend that external RC circuits be used to achieve longer POR delay times (Figure 7-10).
For additional information refer to Application Notes “
Power-Up Considerations”
- AN522 and “
Power-up
Trouble Shooting
” - AN607.
Note: When the device starts normal operation
(exits the reset condition), device operat­ing parameters (voltage, frequency, tem­perature, etc.) must be meet to ensure operation. If these conditions are not met, the device must be held in reset until the operating conditions are met.
1998 Microchip Technology Inc. DS40139D-page 33
PIC12C5XX
FIGURE 7-8: SIMPLIFIED BLOCK DIAGRAM OF ON-CHIP RESET CIRCUIT
FIGURE 7-9: TIME-OUT SEQUENCE ON POWER-UP (MCLR
PULLED LOW)
FIGURE 7-10: TIME-OUT SEQUENCE ON POWER-UP (MCLR
TIED TO VDD): FAST VDD RISE TIME
S Q
R
Q
VDD
GP3/MCLR/VPP
Power-Up
Detect
On-Chip
DRT OSC
POR (Power-On Reset)
WDT Time-out
RESET
CHIP RESET
8-bit Asynch
Ripple Counter
(Start-Up Timer)
MCLRE
SLEEP
Pin Change
Wake-up on pin change
VDD
MCLR
INTERNAL POR
DRT TIME-OUT
INTERNAL RESET
TDRT
VDD
MCLR
INTERNAL POR
DRT TIME-OUT
INTERNAL RESET
TDRT
PIC12C5XX
DS40139D-page 34 1998 Microchip Technology Inc.
FIGURE 7-11: TIME-OUT SEQUENCE ON POWER -UP (MCLR TIED TO VDD): SLOW VDD RISE TIME
VDD
MCLR
INTERNAL POR
DRT TIME-OUT
INTERNAL RESET
TDRT
V1
When VDD rises slowly, the TDRT time-out expires long before VDD has reached its final value. In this example, the chip will reset properly if, and only if, V1 VDD min.
7.5 Device Reset Timer (DRT)
In the PIC12C5XX, DRT runs from RESET and varies based on oscillator selection (see Table 7-5.)
The DRT operates on an internal RC oscillator. The processor is kept in RESET as long as the DRT is active. The DRT delay allows V
DD to rise above VDD
min., and for the oscillator to stabilize. Oscillator circuits based on crystals or ceramic
resonators require a certain time after power-up to establish a stable oscillation. The on-chip DRT keeps the device in a RESET condition for approximately 18 ms after MCLR
has reached a logic high (VIHMCLR)
level. Thus, programming GP3/MCLR
/VPP as MCLR and using an external RC network connected to the MCLR
input is not required in most cases, allowing for savings in cost-sensitive and/or space restricted applications, as well as allowing the use of the GP3/ MCLR
/VPP pin as a general purpose input. The Device Reset time delay will v ary from chip to chip
due to V
DD, temperature, and process variation. See
AC parameters for details. The DRT will also be triggered upon a W atchdog Timer
time-out. This is particularly impor tant for applications using the WDT to wake from SLEEP mode automatically.
7.6 Watchdog Timer (WDT)
The Watchdog Timer (WDT) is a free running on-chip RC oscillator which does not require any external components. This RC oscillator is separate from the external RC oscillator of the GP5/OSC1/CLKIN pin and the internal 4 MHz oscillator. That means that the WDT will run even if the main processor clock has been stopped, for example, by execution of a SLEEP instruction. During normal operation or SLEEP, a WDT reset or wake-up reset generates a device RESET.
The T
O bit (STATUS<4>) will be cleared upon a
Watchdog Timer reset. The WDT can be permanently disabled by
programming the configuration bit WDTE as a '0' (Section 7.1). Refer to the PIC12C5XX Programming Specifications to determine how to access the configuration word.
TABLE 7-5: DRT (DEVICE RESET TIMER
PERIOD)
Oscillator
Configuration
POR Reset
Subsequent
Resets
IntRC & ExtRC
18 ms (typical) 300 µs (typical)
XT & LP 18 ms (typical) 18 ms (typical)
1998 Microchip Technology Inc. DS40139D-page 35
PIC12C5XX
7.6.1 WDT PERIOD The WDT has a nominal time-out period of 18 ms,
(with no prescaler). If a longer time-out period is desired, a prescaler with a division ratio of up to 1:128 can be assigned to the WDT (under software control) by writing to the OPTION register. Thus, a time-out period of a nominal 2.3 seconds can be realized. These periods vary with temperature, V
DD and part-to-
part process variations (see DC specs). Under worst case conditions (V
DD = Min., Temperature
= Max., max. WDT prescaler), it may take several seconds before a WDT time-out occurs.
7.6.2 WDT PROGRAMMING CONSIDERATIONS The CLRWDT instruction clears the WDT and the
postscaler, if assigned to the WDT, and prevents it from timing out and generating a device RESET.
The SLEEP instruction resets the WDT and the postscaler, if assigned to the WDT. This gives the maximum SLEEP time before a WDT wake-up reset.
FIGURE 7-12: WATCHDOG TIMER BLOCK DIAGRAM
TABLE 7-6: SUMMARY OF REGISTERS ASSOCIATED WITH THE WATCHDOG TIMER
Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Value on
Power-On
Reset
Value on All Other
Resets
N/A OPTION GPWU GPPU T0CS T0SE PSA PS2 PS1 PS0 1111 1111 1111 1111 Legend: Shaded boxes = Not used by Watchdog Timer, = unimplemented, read as '0', u = unchanged
1
0
1
0
From Timer0 Clock Source (Figure 6-5)
To Timer0 (Figure 6-4)
Postscaler
WDT Enable
Configuration Bit
PSA
WDT
Time-out
PS2:PS0
PSA
MUX
8 - to - 1 MUX
Postscaler
M
U X
Watchdog
Timer
Note: T0CS, T0SE, PSA, PS2:PS0
are bits in the OPTION register.
PIC12C5XX
DS40139D-page 36 1998 Microchip Technology Inc.
7.7 Time-Out Sequence, Power Down,
and Wake-up from SLEEP Status Bits (TO/PD/GPWUF)
The TO, PD, and GPWUF bits in the STATUS register can be tested to determine if a RESET condition has been caused by a power-up condition, a MCLR
or
Watchdog Timer (WDT) reset.
TABLE 7-7: TO/PD/GPWUF STATUS
AFTER RESET
GPWUF TO PD RESET caused by
0 0 0
WDT wake-up from SLEEP
0 0 u
WDT time-out (not from SLEEP)
0 1 0
MCLR wake-up from SLEEP
0 1 1
Power-up
0 u u
MCLR not during SLEEP
1 1 0
Wake-up from SLEEP on pin change
Legend: Legend: u = unchanged
Note 1: The TO, PD, and GPWUF bits main-
tain their status (u) until a reset occurs. A low-pulse on the MCLR input does not change the TO, PD, and GPWUF status bits.
7.8 Reset on Brown-Out
A brown-out is a condition where device power (VDD) dips below its minimum value, b ut not to z ero , and then recovers. The device should be reset in the event of a brown-out.
To reset PIC12C5XX devices when a brown-out occurs, external brown-out protection circuits may be built, as shown in Figure 7-13 and Figure 7-14.
FIGURE 7-13: BROWN-OUT PROTECTION
CIRCUIT 1
FIGURE 7-14: BROWN-OUT PROTECTION
CIRCUIT 2
This circuit will activate reset when VDD goes below Vz +
0.7V (where Vz = Zener voltage). *Refer to Figure 7-7 and Table 10-1 for internal weak pull-
up on MCLR.
33k
10k
40k*
MCLR
PIC12C5XX
VDD
Q1
VDD
This brown-out circuit is less expensive, although less accurate. Transistor Q1 turns off when V
DD
is below a certain level such that:
*Refer to Figure 7-7 and Table 10-1 for inter nal weak pull-up on MCLR.
VDD
R1
R1 + R2
= 0.7V
R2
40k*
MCLR
PIC12C5XX
R1
Q1
VDD
VDD
1998 Microchip Technology Inc. DS40139D-page 37
PIC12C5XX
7.9 Power-Down Mode (SLEEP)
A device may be powered down (SLEEP) and later powered up (Wake-up from SLEEP).
7.9.1 SLEEP The Power-Down mode is entered by executing a
SLEEP instruction. If enabled, the Watchdog Timer will be cleared but
keeps running, the T
O bit (STATUS<4>) is set, the PD bit (STATUS<3>) is cleared and the oscillator driver is turned off. The I/O por ts maintain the status they had before the SLEEP instruction was executed (driving high, driving low, or hi-impedance).
It should be noted that a RESET generated by a WDT time-out does not drive the MCLR
pin low.
For lowest current consumption while powered down, the T0CKI input should be at V
DD or VSS and the GP3/
MCLR
/VPP pin must be at a logic high level (VIHMC) if
MCLR
is enabled.
7.9.2 WAKE-UP FROM SLEEP The device can wake-up from SLEEP through one of
the following events:
1. An external reset input on GP3/MCLR
/VPP pin,
when configured as MCLR
.
2. A Watchdog Timer time-out reset (if WDT was
enabled).
3. A change on input pin GP0, GP1, or GP3/
MCLR
/VPP when wake-up on change is
enabled.
These events cause a device reset. The T
O, PD, and GPWUF bits can be used to determine the cause of device reset. The T
O bit is cleared if a WDT time-out
occurred (and caused wake-up). The PD
bit, which is set on power-up, is cleared when SLEEP is invoked. The GPWUF bit indicates a change in state while in SLEEP at pins GP0, GP1, or GP3 (since the last time there was a file or bit operation on GP port).
The WDT is cleared when the device wakes from sleep, regardless of the wake-up source.
Caution: Right before entering SLEEP, read the
input pins. When in SLEEP, wake up occurs when the values at the pins change from the state they were in at the last reading. If a wake-up on change occurs and the pins are not read before reentering SLEEP, a wake up will occur immediately even if no pins change while in SLEEP mode.
7.10 Program Verification/Code Protection
If the code protection bit has not been programmed, the on-chip program memory can be read out for verification purposes.
The first 64 locations and the last location can be read regardless of the code protection bit setting.
7.11 ID Locations
Four memory locations are designated as ID locations where the user can store checksum or other code­identification numbers. These locations are not accessible during normal execution but are readable and writable during program/verify.
Use only the lower 4 bits of the ID locations and always program the upper 8 bits as '0's.
PIC12C5XX
DS40139D-page 38 1998 Microchip Technology Inc.
7.12 In-Circuit Serial Programming
The PIC12C5XX microcontrollers can be serially programmed while in the end application circuit. This is simply done with two lines for clock and data, and three other lines for power, ground, and the programming voltage. This allows customers to manufacture boards with unprogrammed devices, and then program the microcontroller just before shipping the product. This also allows the most recent firmware or a custom firmware to be programmed.
The device is placed into a program/verify mode by holding the GP1 and GP0 pins low while raising the MCLR
(VPP) pin from VIL to VIHH (see programming specification). GP1 becomes the programming clock and GP0 becomes the programming data. Both GP1 and GP0 are Schmitt Trigger inputs in this mode.
After reset, a 6-bit command is then supplied to the device. Depending on the command, 14-bits of pro­gram data are then supplied to or from the device, depending if the command was a load or a read. For complete details of serial programming, please refer to the PIC12C5XX Programming Specifications.
A typical in-circuit serial programming connection is shown in Figure 7-15.
FIGURE 7-15: TYPICAL IN-CIRCUIT SERIAL
PROGRAMMING CONNECTION
External Connector Signals
To Normal Connections
To Normal Connections
PIC12C5XX
V
DD
VSS MCLR/VPP
GP1
GP0
+5V
0V
VPP
CLK
Data I/O
VDD
1998 Microchip Technology Inc. DS40139D-page 39
PIC12C5XX
8.0 INSTRUCTION SET SUMMARY
Each PIC12C5XX instruction is a 12-bit word divided into an OPCODE, which specifies the instruction type, and one or more operands which further specify the operation of the instruction. The PIC12C5XX instruction set summary in Table 8-2 groups the instructions into byte-oriented, bit-oriented, and literal and control operations. Table 8-1 shows the opcode field descriptions.
For byte-oriented instructions, 'f' represents a file register designator and 'd' represents a destination designator. The file register designator is used to specify which one of the 32 file registers is to be used by the instruction.
The destination designator specifies where the result of the operation is to be placed. If 'd' is '0', the result is placed in the W register. If 'd' is '1', the result is placed in the file register specified in the instruction.
For bit-oriented instructions, 'b' represents a bit field designator which selects the number of the bit affected by the operation, while 'f' represents the number of the file in which the bit is located.
For literal and control operations, 'k' represents an 8 or 9-bit constant or literal value.
TABLE 8-1: OPCODE FIELD
DESCRIPTIONS
Field Description
f Register file address (0x00 to 0x7F) W Working register (accumulator) b Bit address within an 8-bit file register k Literal field, constant data or label
x
Don't care location (= 0 or 1) The assembler will generate code with x = 0. It is the recommended form of use for compatibility with all Microchip software tools.
d
Destination select;
d = 0 (store result in W) d = 1 (store result in file register 'f')
Default is d = 1
label Label name
TOS Top of Stack
PC Program Counter
WDT Watchdog Timer Counter
TO
Time-Out bit
PD Power-Down bit
dest
Destination, either the W register or the specified register file location
[ ]
Options
( )
Contents
Assigned to
< >
Register bit field
In the set of
i
talics
User defined term (font is courier)
All instructions are executed within a single instruction cycle, unless a conditional test is true or the program counter is changed as a result of an instruction. In this case, the execution takes two instr uction cycles. One instruction cycle consists of four oscillator periods. Thus, for an oscillator frequency of 4 MHz, the normal instruction execution time is 1 µs. If a conditional test is true or the program counter is changed as a result of an instruction, the instruction execution time is 2 µs.
Figure 8-1 shows the three general formats that the instructions can have. All examples in the figure use the following format to represent a hexadecimal number:
0xhhh
where 'h' signifies a hexadecimal digit.
FIGURE 8-1: GENERAL FORMAT FOR
INSTRUCTIONS
Byte-oriented file register operations
11 6 5 4 0
d = 0 for destination W
OPCODE d f (FILE #)
d = 1 for destination f f = 5-bit file register address
Bit-oriented file register operations
11 8 7 5 4 0
OPCODE b (BIT #) f (FILE #)
b = 3-bit bit address f = 5-bit file register address
Literal and control operations (except GOTO)
11 8 7 0
OPCODE k (literal)
k = 8-bit immediate value
Literal and control operations - GOTO instruction
11 9 8 0
OPCODE k (literal)
k = 9-bit immediate value
PIC12C5XX
DS40139D-page 40 1998 Microchip Technology Inc.
TABLE 8-2: INSTRUCTION SET SUMMARY
Mnemonic,
Operands Description Cycles
12-Bit Opcode
Status
Affected NotesMSb LSb
ADDWF ANDWF CLRF CLRW COMF DECF DECFSZ INCF INCFSZ IORWF MOVF MOVWF NOP RLF RRF SUBWF SWAPF XORWF
f,d f,d f – f, d f, d f, d f, d f, d f, d f, d f – f, d f, d f, d f, d f, d
Add W and f AND W with f Clear f Clear W Complement f Decrement f Decrement f, Skip if 0 Increment f Increment f, Skip if 0 Inclusive OR W with f Move f Move W to f No Operation Rotate left f through Carry Rotate right f through Carry Subtract W from f Swap f Exclusive OR W with f
1 1 1 1 1 1
1(2)
1
1(2)
1 1 1 1 1 1 1 1 1
0001 0001 0000 0000 0010 0000 0010 0010 0011 0001 0010 0000 0000 0011 0011 0000 0011 0001
11df 01df 011f 0100 01df 11df 11df 10df 11df 00df 00df 001f 0000 01df 00df 10df 10df 10df
ffff ffff ffff 0000 ffff ffff ffff ffff ffff ffff ffff ffff 0000 ffff ffff ffff ffff ffff
C,DC,Z
Z Z Z Z Z
None
Z
None
Z
Z None None
C
C
C,DC,Z
None
Z
1,2,4
2,4
4
2,4 2,4 2,4 2,4 2,4 2,4 1,4
2,4 2,4
1,2,4
2,4 2,4
BIT-ORIENTED FILE REGISTER OPERATIONS BCF
BSF BTFSC BTFSS
f, b f, b f, b f, b
Bit Clear f Bit Set f Bit Test f, Skip if Clear Bit Test f, Skip if Set
1
1 1 (2) 1 (2)
0100 0101 0110 0111
bbbf bbbf bbbf bbbf
ffff ffff ffff ffff
None None None None
2,4 2,4
LITERAL AND CONTROL OPERATIONS ANDLW
CALL CLRWDT GOTO IORLW MOVLW OPTION RETLW SLEEP TRIS XORLW
k k k k k k – k – f k
AND literal with W Call subroutine Clear Watchdog Timer Unconditional branch Inclusive OR Literal with W Move Literal to W Load OPTION register Return, place Literal in W Go into standby mode Load TRIS register Exclusive OR Literal to W
1
2
1
2
1
1
1
2
1
1
1
1110 1001 0000 101k 1101 1100 0000 1000 0000 0000 1111
kkkk kkkk 0000 kkkk kkkk kkkk 0000 kkkk 0000 0000 kkkk
kkkk kkkk 0100 kkkk kkkk kkkk 0010 kkkk 0011 0fff kkkk
Z
None
T
O, PD
None
Z None None None
T
O, PD
None
Z
1
3
Note 1: The 9th bit of the program counter will be forced to a '0' by any instruction that writes to the PC except f or GOTO .
(Section 4.6)
2: When an I/O register is modified as a function of itself (e.g. MOVF GPIO, 1), the value used will be that value
present on the pins themselves. For example, if the data latch is '1' for a pin configured as input and is driven low by an external device , the data will be written back with a '0'.
3: The instruction TRIS f, where f = 6 causes the contents of the W register to be written to the tristate latches of
GPIO. A '1' forces the pin to a hi-impedance state and disables the output buffers.
4: If this instruction is executed on the TMR0 register (and, where applicab le , d = 1), the prescaler will be cleared
(if assigned to TMR0).
1998 Microchip Technology Inc. DS40139D-page 41
PIC12C5XX
ADDWF Add W and f
Syntax: [
label
] ADDWF f,d
Operands: 0 f 31
d ∈ [0,1] Operation: (W) + (f) (dest) Status Affected: C, DC, Z Encoding:
0001 11df ffff
Description:
Add the contents of the W register and
register 'f'. If 'd' is 0 the result is stored
in the W register . If 'd' is '1' the result is
stored back in register 'f'
. Words: 1 Cycles: 1 Example:
ADDWF FSR, 0
Before Instruction
W = 0x17 FSR = 0xC2
After Instruction
W = 0xD9 FSR = 0xC2
ANDLW And literal with W
Syntax: [
label
] ANDLW k Operands: 0 k 255 Operation: (W).AND. (k) (W) Status Affected: Z Encoding:
1110 kkkk kkkk
Description:
The contents of the W register are AND’ed with the eight-bit literal 'k'. The result is placed in the W register
. Words: 1 Cycles: 1 Example:
ANDLW 0x5F
Before Instruction
W = 0xA3
After Instruction
W = 0x03
ANDWF AND W with f
Syntax: [
label
] ANDWF f,d
Operands: 0 f 31
d ∈ [0,1] Operation: (W) .AND. (f) (dest) Status Affected: Z Encoding:
0001 01df ffff
Description:
The contents of the W register are
AND’ed with register 'f'. If 'd' is 0 the
result is stored in the W register . If 'd' is
'1' the result is stored back in register 'f'
. Words: 1 Cycles: 1 Example:
ANDWF FSR, 1
Before Instruction
W = 0x17 FSR = 0xC2
After Instruction
W = 0x17 FSR = 0x02
BCF Bit Clear f
Syntax: [
label
] BCF f,b
Operands: 0 f 31
0 b 7 Operation: 0 (f<b>) Status Affected: None Encoding:
0100 bbbf ffff
Description:
Bit 'b' in register 'f' is cleared.
Words: 1 Cycles: 1 Example:
BCF FLAG_REG, 7
Before Instruction
FLAG_REG = 0xC7
After Instruction
FLAG_REG = 0x47
PIC12C5XX
DS40139D-page 42 1998 Microchip Technology Inc.
BSF Bit Set f
Syntax: [
label
] BSF f,b
Operands: 0 f 31
0 b 7 Operation: 1 (f<b>) Status Affected: None Encoding:
0101 bbbf ffff
Description:
Bit 'b' in register 'f' is set.
Words: 1 Cycles: 1 Example:
BSF FLAG_REG, 7
Before Instruction
FLAG_REG = 0x0A
After Instruction
FLAG_REG = 0x8A
BTFSC Bit Test f, Skip if Clear
Syntax: [
label
] BTFSC f,b
Operands: 0 f 31
0 b 7 Operation: skip if (f<b>) = 0 Status Affected: None Encoding: 0110
bbbf ffff
Description:
If bit 'b' in register 'f' is 0 then the next
instruction is skipped.
If bit 'b' is 0 then the next instruction
fetched during the current instruction
execution is discarded, and an NOP is
executed instead, making this a 2 cycle
instruction.
Words: 1 Cycles: 1(2) Example:
HERE
FALSE
TRUE
BTFSC GOTO
FLAG,1 PROCESS_CODE
Before Instruction
PC = address (HERE)
After Instruction
if FLAG<1> = 0, PC = address (TRUE); if FLAG<1> = 1, PC = address(FALSE)
BTFSS Bit Test f, Skip if Set
Syntax: [
label
] BTFSS f,b
Operands: 0 f 31
0 b < 7 Operation: skip if (f<b>) = 1 Status Affected: None Encoding:
0111 bbbf ffff
Description:
If bit 'b' in register 'f' is '1' then the next
instruction is skipped.
If bit 'b' is '1', then the next instruction
fetched during the current instruction
execution, is discarded and an NOP is
executed instead, making this a 2 cycle
instruction.
Words: 1 Cycles: 1(2) Example:
HERE BTFSS FLAG,1
FALSE GOTO PROCESS_CODE
TRUE
Before Instruction
PC = address (HERE)
After Instruction
If FLAG<1> = 0, PC = address (FALSE); if FLAG<1> = 1, PC = address (TRUE)
1998 Microchip Technology Inc. DS40139D-page 43
PIC12C5XX
CALL Subroutine Call
Syntax: [
label
] CALL k Operands: 0 k 255 Operation: (PC) + 1 Top of Stack;
k PC<7:0>; (STATUS<6:5>) PC<10:9>;
0 PC<8> Status Affected: None Encoding:
1001 kkkk kkkk
Description:
Subroutine call. First, return address
(PC+1) is pushed onto the stack. The
eight bit immediate address is loaded
into PC bits <7:0>. The upper bits
PC<10:9> are loaded from STA-
TUS<6:5>, PC<8> is cleared. CALL is a
two cycle instruction.
Words: 1 Cycles: 2 Example:
HERE CALL THERE
Before Instruction
PC = address (HERE)
After Instruction
PC = address (THERE) TOS= address (HERE + 1)
CLRF Clear f
Syntax: [
label
] CLRF f Operands: 0 f 31 Operation: 00h (f);
1 Z Status Affected: Z Encoding:
0000 011f ffff
Description:
The contents of register 'f' are cleared
and the Z bit is set.
Words: 1 Cycles: 1 Example:
CLRF FLAG_REG
Before Instruction
FLAG_REG = 0x5A
After Instruction
FLAG_REG = 0x00 Z = 1
CLRW Clear W
Syntax: [
label
] CLRW Operands: None Operation: 00h (W);
1 Z Status Affected: Z Encoding:
0000 0100 0000
Description:
The W register is cleared. Zero bit (Z)
is set.
Words: 1 Cycles: 1 Example:
CLRW
Before Instruction
W = 0x5A
After Instruction
W = 0x00 Z = 1
CLRWDT Clear Watchdog Timer
Syntax: [
label
] CLRWDT Operands: None Operation: 00h WDT;
0 WDT prescaler (if assigned); 1 T
O;
1 PD Status Affected: TO, PD Encoding:
0000 0000 0100
Description:
The CLRWDT instruction resets the
WDT. It also resets the prescaler, if the
prescaler is assigned to the WDT and
not Timer0. Status bits TO and PD are
set.
Words: 1 Cycles: 1 Example:
CLRWDT
Before Instruction
WDT counter = ?
After Instruction
WDT counter = 0x00 WDT prescale = 0 TO = 1 PD = 1
PIC12C5XX
DS40139D-page 44 1998 Microchip Technology Inc.
COMF Complement f
Syntax: [
label
] COMF f,d
Operands: 0 f 31
d [0,1]
Operation: (f
) (dest) Status Affected: Z Encoding:
0010 01df ffff
Description:
The contents of register 'f' are comple­mented. If 'd' is 0 the result is stored in the W register. If 'd' is 1 the result is stored back in register 'f'.
Words: 1 Cycles: 1 Example:
COMF REG1,0
Before Instruction
REG1 = 0x13
After Instruction
REG1 = 0x13 W = 0xEC
DECF Decrement f
Syntax: [
label
] DECF f,d
Operands: 0 f 31
d [0,1] Operation: (f) – 1 (dest) Status Affected: Z Encoding:
0000 11df ffff
Description:
Decrement register 'f'. If 'd' is 0 the
result is stored in the W register . If 'd' is
1 the result is stored back in register 'f'.
Words: 1 Cycles: 1 Example:
DECF CNT,
1
Before Instruction
CNT = 0x01 Z = 0
After Instruction
CNT = 0x00 Z = 1
DECFSZ Decrement f, Skip if 0
Syntax: [
label
] DECFSZ f,d
Operands: 0 f 31
d [0,1] Operation: (f) – 1 d; skip if result = 0 Status Affected: None Encoding:
0010 11df ffff
Description:
The contents of register 'f' are decre-
mented. If 'd' is 0 the result is placed in
the W register. If 'd' is 1 the result is
placed back in register 'f'.
If the result is 0, the next instruction,
which is already fetched, is discarded
and an NOP is executed instead mak-
ing it a two cycle instruction.
Words: 1 Cycles: 1(2) Example:
HERE DECFSZ CNT, 1
GOTO LOOP
CONTINUE •
Before Instruction
PC = address (HERE)
After Instruction
CNT = CNT - 1; if CNT = 0, PC = address (CONTINUE); if CNT 0, PC = address (HERE+1)
GOTO Unconditional Branch
Syntax: [
label
] GOTO k Operands: 0 k 511 Operation: k PC<8:0>;
STATUS<6:5> PC<10:9> Status Affected: None Encoding:
101k kkkk kkkk
Description:
GOTO is an unconditional branch. The
9-bit immediate value is loaded into PC
bits <8:0>. The upper bits of PC are
loaded from STATUS<6:5>. GOTO is a
two cycle instruction.
Words: 1 Cycles: 2 Example:
GOTO THERE
After Instruction
PC = address (THERE)
1998 Microchip Technology Inc. DS40139D-page 45
PIC12C5XX
INCF Increment f
Syntax: [
label
] INCF f,d
Operands: 0 f 31
d [0,1] Operation: (f) + 1 (dest) Status Affected: Z Encoding:
0010 10df ffff
Description:
The contents of register 'f' are incre-
mented. If 'd' is 0 the result is placed in
the W register. If 'd' is 1 the result is
placed back in register 'f'.
Words: 1 Cycles: 1 Example:
INCF CNT,
1
Before Instruction
CNT = 0xFF Z = 0
After Instruction
CNT = 0x00 Z = 1
INCFSZ Increment f, Skip if 0
Syntax: [
label
] INCFSZ f,d
Operands: 0 f 31
d [0,1] Operation: (f) + 1 (dest), skip if result = 0 Status Affected: None Encoding:
0011 11df ffff
Description:
The contents of register 'f' are incre-
mented. If 'd' is 0 the result is placed in
the W register. If 'd' is 1 the result is
placed back in register 'f'.
If the result is 0, then the next instruc-
tion, which is already fetched, is dis-
carded and an NOP is executed
instead making it a two cycle instruc-
tion.
Words: 1 Cycles: 1(2) Example:
HERE INCFSZ CNT, 1
GOTO LOOP
CONTINUE •
Before Instruction
PC = address (HERE)
After Instruction
CNT = CNT + 1; if CNT = 0, PC = address (CONTINUE); if CNT 0, PC = address (HERE +1)
IORLW Inclusive OR literal with W
Syntax: [
label
] IORLW k Operands: 0 k 255 Operation: (W) .OR. (k) (W) Status Affected: Z Encoding:
1101 kkkk kkkk
Description:
The contents of the W register are OR’ed with the eight bit literal 'k'. The result is placed in the W register.
Words: 1 Cycles: 1 Example:
IORLW 0x35
Before Instruction
W = 0x9A
After Instruction
W = 0xBF Z = 0
IORWF Inclusive OR W with f
Syntax: [
label
] IORWF f,d Operands: 0 f 31
d [0,1] Operation: (W).OR. (f) (dest) Status Affected: Z Encoding:
0001 00df ffff
Description:
Inclusive OR the W register with regis-
ter 'f'. If 'd' is 0 the result is placed in
the W register. If 'd' is 1 the result is
placed back in register 'f'.
Words: 1 Cycles: 1 Example:
IORWF RESULT, 0
Before Instruction
RESULT = 0x13 W = 0x91
After Instruction
RESULT = 0x13 W = 0x93 Z = 0
PIC12C5XX
DS40139D-page 46 1998 Microchip Technology Inc.
MOVF Move f
Syntax: [
label
] MOVF f,d
Operands: 0 f 31
d [0,1] Operation: (f) (dest) Status Affected: Z Encoding:
0010 00df ffff
Description:
The contents of register 'f' is moved to
destination 'd'. If 'd' is 0, destination is
the W register. If 'd' is 1, the destination
is file register 'f'. 'd' is 1 is useful to test
a file register since status flag Z is
affected.
Words: 1 Cycles: 1 Example:
MOVF FSR, 0
After Instruction
W = value in FSR register
MOVLW Move Literal to W
Syntax: [
label
] MOVLW k Operands: 0 k 255 Operation: k (W) Status Affected: None Encoding:
1100 kkkk kkkk
Description:
The eight bit literal 'k' is loaded into the W register. The don’t cares will assem­ble as 0s.
Words: 1 Cycles: 1 Example:
MOVLW 0x5A
After Instruction
W = 0x5A
MOVWF Move W to f
Syntax: [
label
] MOVWF f Operands: 0 f 31 Operation: (W) (f) Status Affected: None Encoding:
0000 001f ffff
Description:
Move data from the W register to regis­ter 'f'
. Words: 1 Cycles: 1 Example:
MOVWF TEMP_REG
Before Instruction
TEMP_REG = 0xFF W = 0x4F
After Instruction
TEMP_REG = 0x4F W = 0x4F
NOP No Operation
Syntax: [
label
] NOP Operands: None Operation: No operation Status Affected: None Encoding:
0000 0000 0000
Description: No operation. Words: 1 Cycles: 1 Example:
NOP
1998 Microchip Technology Inc. DS40139D-page 47
PIC12C5XX
OPTION Load OPTION Register
Syntax: [
label
] OPTION Operands: None Operation: (W) OPTION Status Affected: None Encoding:
0000 0000 0010
Description:
The content of the W register is loaded into the OPTION register.
Words: 1 Cycles: 1 Example
OPTION
Before Instruction
W = 0x07
After Instruction
OPTION = 0x07
RETLW Return with Literal in W
Syntax: [
label
] RETLW k Operands: 0 k 255 Operation: k (W);
TOS PC Status Affected: None Encoding:
1000 kkkk kkkk
Description:
The W register is loaded with the eight
bit literal 'k'. The program counter is
loaded from the top of the stack (the
return address). This is a two cycle
instruction.
Words: 1 Cycles: 2 Example:
TABLE
CALL TABLE ;W contains
;table offset
;value.
• ;W now has table
• ;value.
ADDWF PC ;W = offset
RETLW k1 ;Begin table
RETLW k2 ;
RETLW kn ; End of table
Before Instruction
W = 0x07
After Instruction
W = value of k8
RLF Rotate Left f through Carry
Syntax: [
label
] RLF f,d
Operands: 0 f 31
d [0,1] Operation: See description below Status Affected: C Encoding:
0011 01df ffff
Description:
The contents of register 'f' are rotated
one bit to the left through the Carry
Flag. If 'd' is 0 the result is placed in the
W register. If 'd' is 1 the result is stored
back in register 'f'.
Words: 1 Cycles: 1 Example:
RLF REG1,0
Before Instruction
REG1 = 1110 0110 C = 0
After Instruction
REG1 = 1110 0110 W = 1100 1100 C = 1
RRF Rotate Right f through Carry
Syntax: [
label
] RRF f,d
Operands: 0 f 31
d [0,1] Operation: See description below Status Affected: C Encoding:
0011 00df ffff
Description:
The contents of register 'f' are rotated
one bit to the right through the Carry
Flag. If 'd' is 0 the result is placed in the
W register. If 'd' is 1 the result is placed
back in register 'f'.
Words: 1 Cycles: 1 Example:
RRF REG1,0
Before Instruction
REG1 = 1110 0110 C = 0
After Instruction
REG1 = 1110 0110 W = 0111 0011 C = 0
C
register 'f'
C
register 'f'
PIC12C5XX
DS40139D-page 48 1998 Microchip Technology Inc.
SLEEP Enter SLEEP Mode
Syntax:
[
label
]
SLEEP Operands: None Operation: 00h WDT;
0 WDT prescaler; 1 T
O;
0 PD Status Affected: TO, PD, GPWUF Encoding:
0000 0000 0011
Description:
Time-out status bit (TO) is set. The
power down status bit (PD) is cleared.
GPWUF is unaffected.
The WDT and its prescaler are
cleared.
The processor is put into SLEEP mode
with the oscillator stopped. See sec-
tion on SLEEP for more details.
Words: 1 Cycles: 1 Example: SLEEP
SUBWF Subtract W from f
Syntax:
[
label
] SUBWF f,d
Operands: 0 f 31
d [0,1] Operation: (f) – (W) → (dest) Status Affected: C, DC, Z Encoding:
0000 10df ffff
Description:
Subtract (2’s complement method) the
W register from register 'f'. If 'd' is 0 the
result is stored in the W register . If 'd' is
1 the result is stored back in register 'f'.
Words: 1 Cycles: 1 Example 1
:
SUBWF REG1, 1
Before Instruction
REG1 = 3 W = 2 C = ?
After Instruction
REG1 = 1 W = 2 C = 1 ; result is positive
Example 2:
Before Instruction
REG1 = 2 W = 2 C = ?
After Instruction
REG1 = 0 W = 2 C = 1 ; result is zero
Example 3:
Before Instruction
REG1 = 1 W = 2 C = ?
After Instruction
REG1 = FF W = 2 C = 0 ; result is negative
1998 Microchip Technology Inc. DS40139D-page 49
PIC12C5XX
SWAPF Swap Nibbles in f
Syntax: [
label
] SWAPF f,d
Operands: 0 f 31
d [0,1]
Operation: (f<3:0>) (dest<7:4>);
(f<7:4>) (dest<3:0>) Status Affected: None Encoding:
0011 10df ffff
Description:
The upper and lower nibbles of register
'f' are exchanged. If 'd' is 0 the result is
placed in W register . If 'd' is 1 the result
is placed in register 'f'.
Words: 1 Cycles: 1 Example
SWAPF
REG1, 0
Before Instruction
REG1 = 0xA5
After Instruction
REG1 = 0xA5 W = 0X5A
TRIS Load TRIS Register
Syntax: [
label
] TRIS f
Operands: f =
6
Operation: (W) TRIS register f Status Affected: None Encoding:
0000 0000 0fff
Description:
TRIS register 'f' (f = 6) is loaded with the
contents of the W register
Words: 1 Cycles: 1 Example
TRIS GPIO
Before Instruction
W = 0XA5
After Instruction
TRIS = 0XA5
Note: f = 6 for PIC12C5XX only.
XORLW Exclusive OR literal with W
Syntax:
[
label
] XORLW k Operands: 0 k 255 Operation: (W) .XOR. k → (W) Status Affected: Z Encoding:
1111 kkkk kkkk
Description:
The contents of the W register are XOR’ed with the eight bit literal 'k'. The result is placed in the W register.
Words: 1 Cycles: 1 Example: XORLW 0xAF
Before Instruction
W = 0xB5
After Instruction
W = 0x1A
XORWF Exclusive OR W with f
Syntax: [
label
] XORWF f,d
Operands: 0 f 31
d [0,1] Operation: (W) .XOR. (f) → (dest) Status Affected: Z Encoding:
0001 10df ffff
Description:
Exclusive OR the contents of the W
register with register 'f'. If 'd' is 0 the
result is stored in the W register . If 'd' is
1 the result is stored back in register 'f'.
Words: 1 Cycles: 1 Example XORWF
REG,1
Before Instruction
REG = 0xAF W = 0xB5
After Instruction
REG = 0x1A W = 0xB5
PIC12C5XX
DS40139D-page 50 1998 Microchip Technology Inc.
NOTES:
1998 Microchip Technology Inc. DS40139D-page 51
PIC12C5XX
9.0 DEVELOPMENT SUPPORT
9.1 Development Tools
The PICmicrο microcontrollers are supported with a full range of hardware and software dev elopment tools:
• MPLAB™-ICE Real-Time In-Circuit Emulator
• ICEPIC Low-Cost PIC16C5X and PIC16CXXX In-Circuit Emulator
• PRO MATE
II Universal Programmer
• PICSTART
Plus Entry-Level Prototype
Programmer
• SIMICE
• PICDEM-1 Low-Cost Demonstration Board
• PICDEM-2 Low-Cost Demonstration Board
• PICDEM-3 Low-Cost Demonstration Board
• MPASM Assembler
• MPLABSIM Software Simulator
• MPLAB-C17 (C Compiler)
• Fuzzy Logic Development System (
fuzzy
TECH−MP)
• K
EELOQ
®
Evaluation Kits and Programmer
9.2 MPLAB-ICE: High Performance
Universal In-Circuit Emulator with MPLAB IDE
The MPLAB-ICE Universal In-Circuit Emulator is intended to provide the product development engineer with a complete microcontroller design tool set for PICmicro microcontrollers (MCUs). MPLAB-ICE is sup­plied with the MPLAB Integrated Development En viron­ment (IDE), which allows editing, “make” and download, and source debugging from a single envi­ronment.
Interchangeable processor modules allow the system to be easily reconfigured for emulation of different pro­cessors. The universal architecture of the MPLAB-ICE allows expansion to support all new Microchip micro­controllers.
The MPLAB-ICE Emulator System has been designed as a real-time emulation system with advanced fea­tures that are generally found on more expensive development tools. The PC compatible 386 (and higher) machine platform and Microsoft Windows
3.x or Windows 95 environment were chosen to best make these features available to you, the end user.
MPLAB-ICE is available in two versions. MPLAB-ICE 1000 is a basic, low-cost emulator system with simple trace capabilities. It shares processor mod­ules with the MPLAB-ICE 2000. This is a full-featured emulator system with enhanced trace, trigger, and data monitoring features. Both systems will operate across the entire operating speed reange of the PICmicro MCU.
9.3 ICEPIC: Low-Cost PICmicro™ In-Circuit Emulator
ICEPIC is a low-cost in-circuit emulator solution for the Microchip PIC12CXXX, PIC16C5X and PIC16CXXX families of 8-bit OTP microcontrollers.
ICEPIC is designed to operate on PC-compatible machines ranging from 386 through Pentium based machines under Windows 3.x, Windows 95, or Win­dows NT environment. ICEPIC features real time, non­intrusive emulation.
9.4 PRO MATE II: Universal Programmer
The PRO MATE II Universal Programmer is a full-fea­tured programmer capable of operating in stand-alone mode as well as PC-hosted mode. PRO MATE II is CE compliant.
The PRO MATE II has programmable V
DD and VPP
supplies which allows it to verify programmed memory at V
DD min and VDD max for maximum reliability. It has
an LCD display for displaying error messages, keys to enter commands and a modular detachable socket assembly to support various package types. In stand­alone mode the PRO MATE II can read, verify or pro­gram PIC12CXXX, PIC14C000, PIC16C5X, PIC16CXXX and PIC17CXX devices. It can also set configuration and code-protect bits in this mode.
9.5 PICSTART Plus Entry Level Development System
The PICSTART programmer is an easy-to-use, low­cost prototype programmer. It connects to the PC via one of the COM (RS-232) ports. MPLAB Integrated Development Environment software makes using the programmer simple and efficient. PICSTART Plus is not recommended for production programming.
PICSTART Plus supports all PIC12CXXX, PIC14C000, PIC16C5X, PIC16CXXX and PIC17CXX devices with up to 40 pins. Larger pin count devices such as the PIC16C923, PIC16C924 and PIC17C756 may be sup­ported with an adapter socket. PICSTART Plus is CE compliant.
PIC12C5XX
DS40139D-page 52 1998 Microchip Technology Inc.
9.6 SIMICE Entry-Level Hardware Simulator
SIMICE is an entry-level hardware development sys­tem designed to operate in a PC-based environment with Microchip’s simulator MPLAB™-SIM. Both SIM­ICE and MPLAB-SIM run under Microchip Technol­ogy’s MPLAB Integrated Development Environment (IDE) software. Specifically, SIMICE provides hardware simulation for Microchip’s PIC12C5XX, PIC12CE5XX, and PIC16C5X families of PICmicro™ 8-bit microcon­trollers. SIMICE works in conjunction with MPLAB-SIM to provide non-real-time I/O port emulation. SIMICE enables a developer to run simulator code for dr iving the target system. In addition, the target system can provide input to the simulator code. This capability allows for simple and interactive debugging without having to manually generate MPLAB-SIM stimulus files. SIMICE is a valuable debugging tool for entry­level system development.
9.7 PICDEM-1 Low-Cost PICmicro Demonstration Board
The PICDEM-1 is a simple board which demonstrates the capabilities of several of Microchip’s microcontrol­lers. The microcontrollers supported are: PIC16C5X (PIC16C54 to PIC16C58A), PIC16C61, PIC16C62X, PIC16C71, PIC16C8X, PIC17C42, PIC17C43 and PIC17C44. All necessary hardware and software is included to run basic demo programs. The users can program the sample microcontrollers provided with the PICDEM-1 board, on a PRO MATE II or PICSTART-Plus programmer, and easily test firm­ware. The user can also connect the PICDEM-1 board to the MPLAB-ICE emulator and download the firmware to the emulator for testing. Additional proto­type area is available for the user to build some addi­tional hardware and connect it to the microcontroller socket(s). Some of the features include an RS-232 interface, a potentiometer for simulated analog input, push-button switches and eight LEDs connected to PORTB.
9.8 PICDEM-2 Low-Cost PIC16CXX Demonstration Board
The PICDEM-2 is a simple demonstration board that supports the PIC16C62, PIC16C64, PIC16C65, PIC16C73 and PIC16C74 microcontrollers. All the necessary hardware and software is included to run the basic demonstration programs. The user can program the sample microcontrollers provided with the PICDEM-2 board, on a PRO MATE II pro­grammer or PICSTART-Plus, and easily test firmware. The MPLAB-ICE emulator may also be used with the PICDEM-2 board to test firmware. Additional prototype area has been provided to the user for adding addi­tional hardware and connecting it to the microcontroller socket(s). Some of the f eatures include a RS-232 inter­face, push-button switches, a potentiometer for simu­lated analog input, a Serial EEPROM to demonstrate usage of the I
2
C bus and separate headers for connec-
tion to an LCD module and a keypad.
9.9 PICDEM-3 Low-Cost PIC16CXXX Demonstration Board
The PICDEM-3 is a simple demonstration board that supports the PIC16C923 and PIC16C924 in the PLCC package. It will also support future 44-pin PLCC microcontrollers with a LCD Module. All the neces­sary hardware and software is included to run the basic demonstration programs. The user can pro­gram the sample microcontrollers provided with the PICDEM-3 board, on a PRO MATE II program­mer or PICSTART Plus with an adapter socket, and easily test firmware. The MPLAB-ICE emulator may also be used with the PICDEM-3 board to test firm­ware. Additional prototype area has been provided to the user for adding hardware and connecting it to the microcontroller socket(s). Some of the f eatures include an RS-232 interface, push-button switches, a potenti­ometer for simulated analog input, a thermistor and separate headers for connection to an external LCD module and a keypad. Also provided on the PICDEM-3 board is an LCD panel, with 4 commons and 12 seg­ments, that is capable of displaying time, temperature and day of the week. The PICDEM-3 provides an addi­tional RS-232 interface and Windows 3.1 software for showing the demultiplex ed LCD signals on a PC. A sim­ple serial interface allows the user to construct a hard­ware demultiplexer for the LCD signals.
1998 Microchip Technology Inc. DS40139D-page 53
PIC12C5XX
9.10 MPLAB Integrated Development Environment Software
The MPLAB IDE Software brings an ease of software development previously unseen in the 8-bit microcon­troller market. MPLAB is a windows based application which contains:
• A full featured editor
• Three operating modes
- editor
- emulator
- simulator
• A project manager
• Customizable tool bar and key mapping
• A status bar with project information
• Extensive on-line help
MPLAB allows you to:
• Edit your source files (either assembly or ‘C’)
• One touch assemble (or compile) and download
to PICmicro tools (automatically updates all project information)
• Debug using:
- source files
- absolute listing file
The ability to use MPLAB with Microchip’s simulator allows a consistent platform and the ability to easily switch from the low cost simulator to the full featured emulator with minimal retraining due to development tools.
9.11 Assembler (MPASM)
The MPASM Universal Macro Assembler is a PC­hosted symbolic assembler. It suppor ts all microcon­troller series including the PIC12C5XX, PIC14000, PIC16C5X, PIC16CXXX, and PIC17CXX families.
MPASM offers full featured Macro capabilities, condi­tional assembly , and se ver al source and listing formats. It generates various object code formats to support Microchip's development tools as well as third party programmers.
MPASM allows full symbolic debugging from MPLAB­ICE, Microchip’s Universal Emulator System.
MPASM has the following features to assist in dev elop­ing software for specific use applications.
• Provides translation of Assembler source code to
object code for all Microchip microcontrollers.
• Macro assembly capability.
• Produces all the files (Object, Listing, Symbol, and
special) required for symbolic debug with Microchip’s emulator systems.
• Supports Hex (default), Decimal and Octal source
and listing formats.
MPASM provides a rich directive language to support programming of the PICmicro. Directives are helpful in making the development of your assemb le source code shorter and more maintainable.
9.12 Software Simulator (MPLAB-SIM)
The MPLAB-SIM Software Simulator allows code development in a PC host environment. It allows the user to simulate the PICmicro series microcontrollers on an instruction level. On any given instruction, the user may examine or modify any of the data areas or provide external stimulus to any of the pins. The input/ output radix can be set by the user and the execution can be performed in; single step , ex ecute until break, or in a trace mode.
MPLAB-SIM fully supports symbolic debugging using MPLAB-C17 and MPASM. The Software Simulator offers the low cost fle xibility to dev elop and deb ug code outside of the laboratory environment making it an excellent multi-project software development tool.
9.13 MPLAB-C17 Compiler
The MPLAB-C17 Code Development System is a complete ANSI ‘C’ compiler and integrated develop­ment environment for Microchip’ s PIC17CXXX family of microcontrollers. The compiler provides powerful inte­gration capabilities and ease of use not found with other compilers.
For easier source level debugging, the compiler pro­vides symbol information that is compatible with the MPLAB IDE memory display.
9.14 Fuzzy Logic Development System (
fuzzy
TECH-MP)
fuzzy
TECH-MP fuzzy logic development tool is avail­able in two versions - a low cost introductory version, MP Explorer, for designers to gain a comprehensive working knowledge of fuzzy logic system design; and a full-featured version,
fuzzy
TECH-MP, Edition for imple-
menting more complex systems. Both versions include Microchip’s
fuzzy
LAB demon­stration board for hands-on experience with fuzzy logic systems implementation.
9.15 SEEVAL Evaluation and
Programming System
The SEEVAL SEEPROM Designer’s Kit supports all Microchip 2-wire and 3-wire Serial EEPROMs. The kit includes everything necessary to read, write, erase or program special features of any Microchip SEEPROM product including Smart Serials and secure serials. The Total Endurance Disk is included to aid in trade­off analysis and reliability calculations. The total kit can significantly reduce time-to-market and result in an optimized system.
PIC12C5XX
DS40139D-page 54 1998 Microchip Technology Inc.
9.16 KEELOQ Evaluation and Programming Tools
KEELOQ evaluation and programming tools support Microchips HCS Secure Data Products. The HCS eval­uation kit includes an LCD display to show changing codes, a decoder to decode transmissions, and a pro­gramming interface to program test transmitters.
1998 Microchip Technology Inc. DS40139D-page 55
PIC12C5XX
TABLE 9-1: DEVELOPMENT TOOLS FROM MICROCHIP
PIC12C5XX PIC14000 PIC16C5X PIC16CXXX PIC16C6X PIC16C7XX PIC16C8X PIC16C9XX PIC17C4X PIC17C7XX
24CXX 25CXX 93CXX
HCS200 HCS300 HCS301
Emulator Products
MPLAB™-ICE
ü ü ü ü ü ü ü ü ü ü
ICEPIC Low-Cost In-Circuit Emulator
ü ü ü ü ü ü
Software Tools
MPLAB Integrated Development Environment
ü ü ü ü ü ü ü ü ü ü
MPLAB C17* Compiler
ü ü
fuzzy
TECH-MP Explorer/Edition Fuzzy Logic Dev. Tool
ü ü ü ü ü ü ü ü ü
Total Endurance Software Model
ü
Programmers
PICSTARTPlus Low-Cost Universal Dev. Kit
ü ü ü ü ü ü ü ü ü ü
PRO MATE
II Universal Programmer
ü ü ü ü ü ü ü ü ü ü ü ü
KEELOQ
Programmer
ü
Demo Boards
SEEVAL
Designers Kit
ü
SIMICE
ü ü
PICDEM-14A
ü
PICDEM-1
ü ü ü ü
PICDEM-2
ü ü
PICDEM-3
ü
K
EELOQ
®
Evaluation Kit
ü
K
EELOQ
Transponder Kit
ü
PIC12C5XX
DS40139D-page 56 1998 Microchip Technology Inc.
NOTES:
1998 Microchip Technology Inc. DS40139D-page 57
PIC12C5XX
10.0 ELECTRICAL CHARACTERISTICS - PIC12C508/PIC12C509/ PIC12LC508/PIC12LC509
Absolute Maximum Ratings†
Ambient Temperature under bias........................................................................................................... –40˚C to +125˚C
Storage Temperature.............................................................................................................................. –65˚C to +150˚C
Voltage on V
DD with respect to VSS .................................................................................................................0 to +7.5 V
Voltage on MCLR
with respect to VSS...............................................................................................................0 to +14 V
Voltage on all other pins with respect to V
SS ................................................................................–0.6 V to (VDD + 0.6 V)
Total Power Dissipation
(1)
....................................................................................................................................700 mW
Max. Current out of V
SS pin...................................................................................................................................200 mA
Max. Current into V
DD pin......................................................................................................................................150 mA
Input Clamp Current, I
IK (VI < 0 or VI > VDD) ....................................................................................................................±20 mA
Output Clamp Current, I
OK (VO < 0 or VO > VDD) ............................................................................................................±20 mA
Max. Output Current sunk by any I/O pin................................................................................................................25 mA
Max. Output Current sourced by any I/O pin...........................................................................................................25 mA
Max. Output Current sourced by I/O port (GPIO)..................................................................................................100 mA
Max. Output Current sunk by I/O port (GPIO )......................................................................................................100 mA
Note 1: Power Dissipation is calculated as follows: P
DIS = VDD x {IDD - IOH} + {(VDD-VOH) x IOH} + (VOL x IOL)
NOTICE: Stresses above those listed under "Maximum Ratings" may cause permanent damage to the device. This is a stress rating only and functional operation of the device at those or any other conditions above those indicated in the operation listings of this specification is not implied. Exposure to maximum rating conditions for extended periods may affect device reliability.
PIC12C5XX
DS40139D-page 58 1998 Microchip Technology Inc.
10.1 DC CHARACTERISTICS: PIC12C508/509 (Commercial, Industrial, Extended)
DC Characteristics Power Supply Pins
Standard Operating Conditions (unless otherwise specified)
Operating Temperature 0°C TA +70°C (commercial)
–40°C T
A +85°C (industrial)
–40°C T
A +125°C (extended)
Characteristic Sym Min
Typ
(1)
Max Units Conditions
Supply Voltage V
DD 2.5
3.0
5.5
5.5
VVFOSC = DC to 4 MHz (Commercial/
Industrial) F
OSC = DC to 4 MHz (Extended)
RAM Data Retention Voltage
(2)
VDR 1.5* V Device in SLEEP mode
V
DD Start Voltage to ensure
Power-on Reset
VPOR VSS V See section on Power-on Reset for details
V
DD Rise Rate to ensure
Power-on Reset
SVDD 0.05* V/ms See section on Power-on Reset for details
Supply Current
(3)
IDD
IWDT
— — — — —
— — —
1.8
1.8 15 19 19
3.75
3.75
3.75
2.4
2.4 27 35 35
8 9 4
mA mA
µA µA µA µA
µA µA
XT and EXTRC options (Note 4) F
OSC = 4 MHz, VDD = 5.5V
INTRC Option F
OSC = 4 MHz, VDD = 5.5V
LP O
PTION, Commercial Temperature
F
OSC = 32 kHz, VDD = 3.0V, WDT disabled
LP O
PTION, Industrial Temperature
F
OSC = 32 kHz, VDD = 3.0V, WDT disabled
LP O
PTION, Extended Temperature
F
OSC = 32 kHz, VDD = 3.0V, WDT disabled-
V
DD = 3.0V, Commercial
V
DD = 3.0V, Industrial
V
DD = 3.0V, Extended
Power-Down Current
(5)
IPD
— —
0.25
0.25 2
4 5
18
µA µA µA
VDD = 3.0V, Commercial V
DD = 3.0V, Industrial
V
DD = 3.0V, Extended
* These parameters are characterized but not tested. Note 1: Data in the Typical (“Typ”) column is based on characterization results at 25°C. This data is for design guid-
ance only and is not tested.
2: This is the limit to which V
DD can be lowered in SLEEP mode without losing RAM data.
3: The supply current is mainly a function of the operating voltage and frequency. Other factors such as bus
loading, oscillator type, bus rate, internal code execution pattern, and temperature also have an impact on the current consumption.
a) The test conditions for all I
DD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tristated, pulled to V
ss, T0CKI = VDD, MCLR = VDD; WDT enabled/disabled as specified.
b) For standby current measurements, the conditions are the same, except that
the device is in SLEEP mode.
4: Does not include current through Rext. The current through the resistor can be estimated by the
formula: I
R = VDD/2Rext (mA) with Rext in kOhm.
5: The power down current in SLEEP mode does not depend on the oscillator type. Power down current is mea-
sured with the part in SLEEP mode, with all I/O pins in hi-impedance state and tied to V
DD or VSS.
1998 Microchip Technology Inc. DS40139D-page 59
PIC12C5XX
10.2 DC CHARACTERISTICS: PIC12C508/509 (Commercial, Industrial, Extended)
DC CHARACTERISTICS
Standard Operating Conditions (unless otherwise specified)
Operating temperature 0˚C T
A +70˚C (commercial)
–40˚C T
A +85˚C (industrial)
–40°C T
A +125˚C (extended)
Operating voltage V
DD range as described in DC spec Section 10.1 and
Section 10.2.
Param
No.
Characteristic Sym Min Typ†Max Units Conditions
Input Low Voltage
I/O ports V
IL
D030 with TTL buffer VSS - 0.5V V D031 with Schmitt Trigger buffer V
SS - 0.2VDD V
D032 MCLR
, GP2/T0CKI/AN2/INT
(in EXTRC mode)
VSS - 0.2VDD V
D033 OSC1 (in XT, HS and LP) V
SS - 0.3VDD V Note1
Input High Voltage
I/O ports V
IH -
D040 with TTL buffer 2.0 - V
DD V 4.5 VDD 5.5V
D040A 0.8V
DD - VDD V For VDD > 5.5V or VDD < 4.5V
D041 with Schmitt Trigger buffer 0.8V
DD - VDD V For entire VDD range
D042 MCLR
, GP2/T0CKI/AN2/INT 0.8VDD - VDD V
D042A OSC1 (XT, HS and LP) 0.7V
DD - VDD V Note1
D043 OSC1 (in EXTRC mode) 0.9V
DD - VDD V
D070 GPIO weak pull-up current I
PUR 50 250 400 µA VDD = 5V, VPIN = VSS
Input Leakage Current (Notes 2, 3)
D060 I/O ports I
IL - - +1 µA Vss VPIN VDD, Pin at hi-
impedance
D061 MCLR
, GP2/T0CKI - -
+
5
(5)
µA Vss VPIN VDD
D063 OSC1 - - +5 µA Vss ≤ VPIN VDD, XT, HS and LP
osc configuration
Output Low Voltage
D080 I/O ports/CLKOUT V
OL - - 0.6 V IOL = 8.5 mA, VDD = 4.5V,
–40°C to +85°C
D080A - - 0.6 V I
OL = 7.0 mA, VDD = 4.5V,
–40°C to +125°C
D083 OSC2 - - 0.6 V I
OL = 1.6 mA, VDD = 4.5V,
–40°C to +85°C
D083A - - 0.6 V I
OL = 1.2 mA, VDD = 4.5V,
–40°C to +125°C
† Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: In EXTRC oscillator configuration, the OSC1/CLKIN pin is a Schmitt Trigger input. It is not recommended that
the PIC12C5XX be driven with external clock in RC mode.
2: The leakage current on the MCLR
pin is strongly dependent on the applied voltage lev el. The specified levels
represent normal operating conditions. Higher leakage current may be measured at different input voltages.
3: Negative current is defined as coming out of the pin.
4: Extended operating range is Advance Information for this device.
5: When configured as external reset, the input leakage current is the weak pulll-up current of -10mA minimum.
This pull-up is weaker than the standard I/O pull-up.
PIC12C5XX
DS40139D-page 60 1998 Microchip Technology Inc.
Output High Voltage
D090 I/O ports/CLKOUT (Note 3) V
OH VDD - 0.7 - - V IOH = -3.0 mA, VDD = 4.5V,
–40°C to +85°C
D090A V
DD - 0.7 - - V IOH = -2.5 mA, VDD = 4.5V,
–40°C to +125°C
D092 OSC2 V
DD - 0.7 - - V IOH = -1.3 mA, VDD = 4.5V,
–40°C to +85°C
D092A V
DD - 0.7 - - V IOH = -1.0 mA, VDD = 4.5V,
–40°C to +125°C
Capacitive Loading Specs on Output Pins
D100 OSC2 pin C
OSC2 - - 15 pF In XT, HS and LP modes when
external clock is used to drive OSC1.
D101 All I/O pins and OSC2 C
IO - - 50 pF
DC CHARACTERISTICS
Standard Operating Conditions (unless otherwise specified)
Operating temperature 0˚C T
A +70˚C (commercial)
–40˚C T
A +85˚C (industrial)
–40°C T
A +125˚C (extended)
Operating voltage V
DD range as described in DC spec Section 10.1 and
Section 10.2.
Param
No.
Characteristic Sym Min Typ†Max Units Conditions
† Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: In EXTRC oscillator configuration, the OSC1/CLKIN pin is a Schmitt Trigger input. It is not recommended that
the PIC12C5XX be driven with external clock in RC mode.
2: The leakage current on the MCLR
pin is strongly dependent on the applied voltage lev el. The specified levels
represent normal operating conditions. Higher leakage current may be measured at different input voltages.
3: Negative current is defined as coming out of the pin.
4: Extended operating range is Advance Information for this device.
5: When configured as external reset, the input leakage current is the weak pulll-up current of -10mA minimum.
This pull-up is weaker than the standard I/O pull-up.
1998 Microchip Technology Inc. DS40139D-page 61
PIC12C5XX
10.3 DC CHARACTERISTICS: PIC12LC508/509 (Commercial, Industrial)
DC Characteristics Power Supply Pins
Standard Operating Conditions (unless otherwise specified)
Operating Temperature 0°C T
A +70°C (commercial)
–40°C T
A +85°C (industrial)
Characteristic Sym Min
Typ
(1)
Max Units Conditions
Supply Voltage V
DD 2.5
3.0
5.5
5.5
VVFOSC = DC to 4 MHz (Commercial/
Industrial) F
OSC = DC to 4 MHz (Extended)
RAM Data Retention Voltage
(2)
VDR 1.5* V Device in SLEEP mode
V
DD Start Voltage to ensure
Power-on Reset
VPOR VSS V See section on Power-on Reset for details
V
DD Rise Rate to ensure
Power-on Reset
SVDD 0.05* V/ms See section on Power-on Reset for details
Supply Current
(3)
IDD
IWDT
— — — — —
— — —
1.8
1.8 15 19 19
3.75
3.75
3.75
2.4
2.4 27 35 35
8 9 4
mA mA
µA µA µA µA
µA µA
XT and EXTRC options (Note 4) F
OSC = 4 MHz, VDD = 5.5V
INTRC Option F
OSC = 4 MHz, VDD = 5.5V
LP O
PTION, Commercial Temperature
F
OSC = 32 kHz, VDD = 3.0V, WDT disabled
LP O
PTION, Industrial Temperature
F
OSC = 32 kHz, VDD = 3.0V, WDT disabled
LP O
PTION, Extended Temperature
F
OSC = 32 kHz, VDD = 3.0V, WDT disabled-
V
DD = 3.0V, Commercial
V
DD = 3.0V, Industrial
V
DD = 3.0V, Extended
Power-Down Current
(5)
IPD
— —
0.25
0.25 2
4 5
18
µA µA µA
VDD = 3.0V, Commercial V
DD = 3.0V, Industrial
V
DD = 3.0V, Extended
* These parameters are characterized but not tested. Note 1: Data in the Typical (“Typ”) column is based on characterization results at 25°C. This data is for design guid-
ance only and is not tested.
2: This is the limit to which V
DD can be lowered in SLEEP mode without losing RAM data.
3: The supply current is mainly a function of the operating voltage and frequency. Other factors such as bus
loading, oscillator type, bus rate, internal code execution pattern, and temperature also have an impact on the current consumption.
a) The test conditions for all I
DD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tristated, pulled to V
ss, T0CKI = VDD, MCLR = VDD; WDT enabled/disabled as specified.
b) For standby current measurements, the conditions are the same, except that
the device is in SLEEP mode.
4: Does not include current through Rext. The current through the resistor can be estimated by the
formula: I
R = VDD/2Rext (mA) with Rext in kOhm.
5: The power down current in SLEEP mode does not depend on the oscillator type. Power down current is mea-
sured with the part in SLEEP mode, with all I/O pins in hi-impedance state and tied to V
DD or VSS.
PIC12C5XX
DS40139D-page 62 1998 Microchip Technology Inc.
10.4 DC CHARACTERISTICS: PIC12LC508/509 (Commercial, Industrial)
DC CHARACTERISTICS
Standard Operating Conditions (unless otherwise specified)
Operating temperature 0˚C T
A +70˚C (commercial)
–40˚C T
A +85˚C (industrial)
Operating voltage V
DD range as described in DC spec Section 10.1 and
Section 10.2.
Param
No.
Characteristic Sym Min Typ†Max Units Conditions
Input Low Voltage
I/O ports V
IL
D030 with TTL buffer VSS - 0.5V V D031 with Schmitt Trigger buffer V
SS - 0.2VDD V
D032 MCLR
, GP2/T0CKI/AN2/INT
(in EXTRC mode)
VSS - 0.2VDD V
D033 OSC1 (in XT, HS and LP) V
SS - 0.3VDD V Note1
Input High Voltage
I/O ports V
IH -
D040 with TTL buffer 2.0 - V
DD V 4.5 VDD 5.5V
D040A 0.8V
DD - VDD V For VDD > 5.5V or VDD < 4.5V
D041 with Schmitt Trigger buffer 0.8V
DD - VDD V For entire VDD range
D042 MCLR
, GP2/T0CKI/AN2/INT 0.8VDD - VDD V
D042A OSC1 (XT, HS and LP) 0.7V
DD - VDD V Note1
D043 OSC1 (in EXTRC mode) 0.9V
DD - VDD V
D070 GPIO weak pull-up current I
PUR 50 250 400 µA VDD = 5V, VPIN = VSS
Input Leakage Current (Notes 2, 3)
D060 I/O ports I
IL - - +1 µA Vss VPIN VDD, Pin at hi-
impedance
D061 MCLR
, GP2/T0CKI - -
+
5
(5)
µA Vss VPIN VDD
D063 OSC1 - - +5 µA Vss ≤ VPIN VDD, XT, HS and LP
osc configuration
Output Low Voltage
D080 I/O ports/CLKOUT V
OL - - 0.6 V IOL = 8.5 mA, VDD = 4.5V,
–40°C to +85°C
D080A - - 0.6 V I
OL = 7.0 mA, VDD = 4.5V,
–40°C to +125°C
D083 OSC2 - - 0.6 V I
OL = 1.6 mA, VDD = 4.5V,
–40°C to +85°C
D083A - - 0.6 V I
OL = 1.2 mA, VDD = 4.5V,
–40°C to +125°C
† Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: In EXTRC oscillator configuration, the OSC1/CLKIN pin is a Schmitt Trigger input. It is not recommended that
the PIC12C5XX be driven with external clock in RC mode.
2: The leakage current on the MCLR
pin is strongly dependent on the applied voltage lev el. The specified levels
represent normal operating conditions. Higher leakage current may be measured at different input voltages.
3: Negative current is defined as coming out of the pin.
4: Extended operating range is Advance Information for this device.
5: When configured as external reset, the input leakage current is the weak pulll-up current of -10mA minimum.
This pull-up is weaker than the standard I/O pull-up.
1998 Microchip Technology Inc. DS40139D-page 63
PIC12C5XX
Output High Voltage
D090 I/O ports/CLKOUT (Note 3) V
OH VDD - 0.7 - - V IOH = -3.0 mA, VDD = 4.5V,
–40°C to +85°C
D090A V
DD - 0.7 - - V IOH = -2.5 mA, VDD = 4.5V,
–40°C to +125°C
D092 OSC2 V
DD - 0.7 - - V IOH = -1.3 mA, VDD = 4.5V,
–40°C to +85°C
D092A V
DD - 0.7 - - V IOH = -1.0 mA, VDD = 4.5V,
–40°C to +125°C
Capacitive Loading Specs on Output Pins
D100 OSC2 pin C
OSC2 - - 15 pF In XT, HS and LP modes when
external clock is used to drive OSC1.
D101 All I/O pins and OSC2 C
IO - - 50 pF
DC CHARACTERISTICS
Standard Operating Conditions (unless otherwise specified)
Operating temperature 0˚C T
A +70˚C (commercial)
–40˚C T
A +85˚C (industrial)
Operating voltage V
DD range as described in DC spec Section 10.1 and
Section 10.2.
Param
No.
Characteristic Sym Min Typ†Max Units Conditions
† Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: In EXTRC oscillator configuration, the OSC1/CLKIN pin is a Schmitt Trigger input. It is not recommended that
the PIC12C5XX be driven with external clock in RC mode.
2: The leakage current on the MCLR
pin is strongly dependent on the applied voltage lev el. The specified levels
represent normal operating conditions. Higher leakage current may be measured at different input voltages.
3: Negative current is defined as coming out of the pin.
4: Extended operating range is Advance Information for this device.
5: When configured as external reset, the input leakage current is the weak pulll-up current of -10mA minimum.
This pull-up is weaker than the standard I/O pull-up.
PIC12C5XX
DS40139D-page 64 1998 Microchip Technology Inc.
TABLE 10-1: PULL-UP RESISTOR RANGES - PIC12C508/C509
VDD (Volts) Temperature (°C) Min Typ Max Units
GP0/GP1
2.5 –40 38K 42K 63K 25 42K 48K 63K 85 42K 49K 63K
125 50K 55K 63K
5.5 –40 15K 17K 20K 25 18K 20K 23K 85 19K 22K 25K
125 22K 24K 28K
GP3
2.5 –40 285K 346K 417K 25 343K 414K 532K 85 368K 457K 532K
125 431K 504K 593K
5.5 –40 247K 292K 360K 25 288K 341K 437K 85 306K 371K 448K
125 351K 407K 500K
* These parameters are characterized but not tested.
1998 Microchip Technology Inc. DS40139D-page 65
PIC12C5XX
10.5 Timing Parameter Symbology and Load Conditions - PIC12C508/C509
The timing parameter symbols have been created following one of the following formats:
1. TppS2ppS
2. TppS
T
F Frequency T Time Lowercase subscripts (pp) and their meanings:
pp
2 to mc MCLR ck CLKOUT osc oscillator cy cycle time os OSC1 drt device reset timer t0 T0CKI io I/O port wdt watchdog timer Uppercase letters and their meanings:
S
F Fall P Period H High R Rise I Invalid (Hi-impedance) V Valid L Low Z Hi-impedance
FIGURE 10-1: LOAD CONDITIONS - PIC12C508/C509
CL
VSS
Pin
C
L = 50 pF for all pins except OSC2
15 pF for OSC2 in XT, HS or LP
modes when external clock is used to drive OSC1
PIC12C5XX
DS40139D-page 66 1998 Microchip Technology Inc.
10.6 Timing Diagrams and Specifications FIGURE 10-2: EXTERNAL CLOCK TIMING - PIC12C508/C509
TABLE 10-2: EXTERNAL CLOCK TIMING REQUIREMENTS - PIC12C508/C509
AC Characteristics Standard Operating Conditions (unless otherwise specified)
Operating Temperature 0°C T
A +70°C (commercial),
–40°C T
A +85°C (industrial),
–40°C T
A +125°C (extended)
Operating Voltage V
DD range is described in Section 10.1
Parameter
No.
Sym Characteristic Min
Typ
(1)
Max Units Conditions
FOSC
External CLKIN Frequency
(2)
DC 4 MHz XT osc mode DC 200 kHz LP osc mode
Oscillator Frequency
(2)
0.1 4 MHz XT osc mode DC 200 kHz LP osc mode
1 T
OSC
External CLKIN Period
(2)
250 ns EXTRC osc mode 250 ns XT osc mode
5 ms LP osc mode
Oscillator Period
(2)
250 ns EXTRC osc mode 250 10,000 ns XT osc mode
5 ms LP osc mode
2 Tcy
Instruction Cycle Time
(3)
4/FOSC
3 TosL, TosH Clock in (OSC1) Low or High Time 50* ns XT oscillator
2* ms LP oscillator
4 TosR, TosF Clock in (OSC1) Rise or Fall Time 25* ns XT oscillator
50* ns LP oscillator
* These parameters are characterized but not tested.
Note 1: Data in the Typical (“Typ”) column is at 5V, 25°C unless otherwise stated. These parameters are for design
guidance only and are not tested.
2: All specified values are based on characterization data for that particular oscillator type under standard oper-
ating conditions with the device executing code. Exceeding these specified limits may result in an unstable oscillator operation and/or higher than expected current consumption. When an external clock input is used, the “max” cycle time limit is “DC” (no clock) for all devices.
3: Instruction cycle period (T
CY) equals four times the input oscillator time base period.
OSC1
Q4
Q1 Q2
Q3 Q4 Q1
1 3 3
4 4
2
1998 Microchip Technology Inc. DS40139D-page 67
PIC12C5XX
TABLE 10-3: CALIBRATED INTERNAL RC FREQUENCIES - PIC12C508/C509
FIGURE 10-3: I/O TIMING - PIC12C508/C509
AC Characteristics Standard Operating Conditions (unless otherwise specified)
Operating Temperature 0°C T
A +70°C (commercial),
–40°C T
A +85°C (industrial),
–40°C T
A +125°C (extended)
Operating Voltage V
DD range is described in Section 10.1
Parameter
No.
Sym Characteristic Min*
Typ
(1)
Max* Units Conditions
Internal Calibrated RC Frequency 3.64 4.00 4.32 MHz VDD = 5.0V
Internal Calibrated RC Frequency
3.51 4.00 4.26 MHz V
DD = 2.5V
* These parameters are characterized but not tested.
Note 1: Data in the Typical (“Typ”) column is at 5V, 25°C unless otherwise stated. These parameters are for design
guidance only and are not tested.
OSC1
I/O Pin
(input)
I/O Pin
(output)
Q4
Q1
Q2 Q3
17
20, 21
18
Old Value
New Value
Note: All tests must be done with specified capacitive loads (see data sheet) 50 pF on I/O pins and CLKOUT.
19
PIC12C5XX
DS40139D-page 68 1998 Microchip Technology Inc.
TABLE 10-4: TIMING REQUIREMENTS - PIC12C508/C509
FIGURE 10-4: RESET, WATCHDOG TIMER, AND DEVICE RESET TIMER TIMING - PIC12C508/C509
AC Characteristics Standard Operating Conditions (unless otherwise specified)
Operating Temperature 0°C T
A +70°C (commercial)
–40°C T
A +85°C (industrial)
–40°C T
A +125°C (extended)
Operating Voltage V
DD range is described in Section 10.1
Parameter
No. Sym Characteristic Min Typ
(1)
Max Units
17
TosH2ioV
OSC1 (Q1 cycle) to Port out valid
(3)
100* ns
18
TosH2ioI OSC1 (Q2 cycle) to Port input invalid
(I/O in hold time)
TBD ns
19
TioV2osH Port input valid to OSC1
(I/O in setup time)
TBD ns
20
TioR
Port output rise time
(3)
10 25** ns
21
TioF
Port output fall time
(3)
10 25** ns
* These parameters are characterized but not tested.
** These parameters are design targets and are not tested. No characterization data available at this time.
Note 1: Data in the Typical (“Typ”) column is at 5V, 25˚C unless otherwise stated. These parameters are for design
guidance only and are not tested. 2: Measurements are taken in EXTRC mode. 3: See Figure 10-1 for loading conditions.
VDD
MCLR
Internal
POR
DRT
Timeout
Internal
RESET
Watchdog
Timer
RESET
32
31
34
I/O pin
32
32
34
(Note 1)
Note 1: I/O pins must be taken out of hi-impedance mode by enabling the output drivers in software.
30
(Note 2)
2: Runs in MCLR or WDT reset only in XT and LP modes.
1998 Microchip Technology Inc. DS40139D-page 69
PIC12C5XX
TABLE 10-5: RESET, WATCHDOG TIMER, AND DEVICE RESET TIMER - PIC12C508/C509
TABLE 10-6: DRT (DEVICE RESET TIMER PERIOD - PIC12C508/C509)
AC Characteristics Standard Operating Conditions (unless otherwise specified)
Operating Temperature 0°C T
A +70°C (commercial)
–40°C T
A +85°C (industrial)
–40°C T
A +125°C (extended)
Operating Voltage V
DD range is described in Section 10.1
Parameter
No. Sym Characteristic Min Typ
(1)
Max Units Conditions
30
TmcL MCLR Pulse Width (low) 2000* ns VDD = 5 V
31
Twdt Watchdog Timer Time-out Period
(No Prescaler)
9* 18* 30* ms VDD = 5 V (Commercial)
32
TDRT Device Reset Timer Period
(2)
9* 18* 30* ms VDD = 5 V (Commercial)
34
TioZ I/O Hi-impedance from MCLR Low 2000* ns
* These parameters are characterized but not tested.
Note 1: Data in the Typical (“Typ”) column is at 5V, 25°C unless otherwise stated. These parameters are for design
guidance only and are not tested.
Oscillator Configuration POR Reset Subsequent Resets
IntRC & ExtRC 18 ms (typical) 300 µs (typical) XT & LP 18 ms (typical) 18 ms (typical)
PIC12C5XX
DS40139D-page 70 1998 Microchip Technology Inc.
FIGURE 10-5: TIMER0 CLOCK TIMINGS - PIC12C508/C509
TABLE 10-7: TIMER0 CLOCK REQUIREMENTS - PIC12C508/C509
AC Characteristics Standard Operating Conditions (unless otherwise specified)
Operating Temperature 0°C T
A +70°C (commercial)
–40°C T
A +85°C (industrial)
–40°C T
A +125°C (extended)
Operating Voltage V
DD range is described in Section 10.1.
Parameter
No.
Sym Characteristic Min Typ
(1)
Max Units Conditions
40 Tt0H T0CKI High Pulse Width - No Prescaler 0.5 TCY + 20* ns
- With Prescaler 10* ns
41 Tt0L T0CKI Low Pulse Width - No Prescaler 0.5 TCY + 20* ns
- With Prescaler 10* ns
42 Tt0P T0CKI Period 20 or TCY + 40*
N
ns Whichever is greater.
N = Prescale Value
(1, 2, 4,..., 256)
* These parameters are characterized but not tested.
Note 1: Data in the Typical (“Typ”) column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only
and are not tested.
T0CKI
40 41
42
1998 Microchip Technology Inc. DS40139D-page 71
PIC12C5XX
NOTES:
PIC12C5XX
DS40139D-page 72 1998 Microchip Technology Inc.
1998 Microchip Technology Inc. DS40139D-page 73
PIC12C5XX
11.0 DC AND AC CHARACTERISTICS - PIC12C508/PIC12C509/ PIC12LC508/PIC12LC509
The graphs and tables provided in this section are for design guidance and are not tested. In some graphs or tables the data presented are outside specified operating range (e.g., outside specified V
DD range). This is for information
only and devices will operate properly only within the specified range. The data presented in this section is a statistical summary of data collected on units from different lots over a period of
time. “Typical” represents the mean of the distribution while “max” or “min” represents (mean + 3σ) and (mean – 3σ) respectively, where σ is standard deviation.
FIGURE 11-1: CALIBRATED INTERNAL RC FREQUENCY RANGE VS. TEMPERATURE (VDD = 2.5V)
Calibrated Internal RC Frequency Range vs Temperature (Vdd=2.5V)
3.25
3.45
3.65
3.85
4.05
4.25
4.45
-40 25 85 125
Temperature (Deg C)
Frequency (Mhz)
PIC12C5XX
DS40139D-page 74 1998 Microchip Technology Inc.
FIGURE 11-2: CALIBRATED INTERNAL RC FREQUENCY RANGE VS. TEMPERATURE (VDD = 5.0V)
TABLE 11-1: DYNAMIC IDD (TYPICAL) -
WDT ENABLED, 25°C
Oscillator Frequency VDD = 2.5V VDD = 5.5V
External RC 4 MHz 250 µA* 620 µA* Internal RC 4 MHz 420 µA 1.1 mA XT 4 MHz 251 µA 775 µA LP 32 KHz 7 µA 37 µA *Does not include current through external R&C.
Calibrated Internal RC Frequency Range vs Temperature (Vdd=5.0V)
25 85
Temperature (Deg C)
Frequency (Mhz)
FIGURE 11-3: WDT TIMER TIME-OUT
PERIOD vs. VDD
50
45
40
35
30
25
20
15
10
5
2 3 4 5 6 7
V
DD (Volts)
WDT period (mS)
Max +125°C
Max +85°C
Typ +25°C
MIn –40°C
1998 Microchip Technology Inc. DS40139D-page 75
PIC12C5XX
FIGURE 11-4: SHORT DRT PERIOD VS. VDD
FIGURE 11-5: IOH vs. VOH, VDD = 2.5 V
1000
900
800
700
600
500
400
300
200
100
2 3 4 5 6 7
V
DD (Volts)
WDT period (µs)
Max +125°C
Max +85°C
Typ +25°C
MIn –40°C
500m 1.0 1.5
VOH (Volts)
IOH (mA)
2.0 2.5
0
-1
-2
-3
-4
-5
-6
-7
Min +125°C
Max –40°C
Typ +25°C
Min +85°C
FIGURE 11-6: IOH vs. VOH, VDD = 5.5 V
FIGURE 11-7: IOL vs. VOL, VDD = 2.5 V
3.5 4.0 4.5
VOH (Volts)
IOH (mA)
5.0 5.5
0
-5
-10
-15
-20
-25
-30
Min +125°C
Max –40°C
Typ +25°C
Min +85°C
25
20
15
10
5
0
250.0m 500.0m 1.0 V
OL (Volts)
IOL (mA)
Min +85°C
Max –40°C
Typ +25°C
0
Min +125°C
PIC12C5XX
DS40139D-page 76 1998 Microchip Technology Inc.
FIGURE 11-8: IOL vs. VOL, VDD = 5.5 V
NOTES:
50
40
30
20
10
0
500.0m 750.0m 1.0 V
OL (Volts)
IOL (mA)
250.0m
Min +85°C
Max –40°C
Typ +25°C
Min +125°C
1998 Microchip Technology Inc. Preliminary DS40139D-page 77
PIC12C5XX
12.0 ELECTRICAL CHARACTERISTICS - PIC12C508A/PIC12C509A/ PIC12LC508A/PIC12LC509A
Absolute Maximum Ratings†
Ambient Temperature under bias........................................................................................................... –40˚C to +125˚C
Storage Temperature.............................................................................................................................. –65˚C to +150˚C
Voltage on V
DD with respect to VSS .................................................................................................................0 to +7.0 V
Voltage on MCLR
with respect to VSS...............................................................................................................0 to +14 V
Voltage on all other pins with respect to V
SS ................................................................................–0.6 V to (VDD + 0.6 V)
Total Power Dissipation
(1)
....................................................................................................................................700 mW
Max. Current out of V
SS pin...................................................................................................................................200 mA
Max. Current into V
DD pin......................................................................................................................................150 mA
Input Clamp Current, I
IK (VI < 0 or VI > VDD) ....................................................................................................................±20 mA
Output Clamp Current, I
OK (VO < 0 or VO > VDD) ............................................................................................................±20 mA
Max. Output Current sunk by any I/O pin................................................................................................................25 mA
Max. Output Current sourced by any I/O pin...........................................................................................................25 mA
Max. Output Current sourced by I/O port (GPIO)..................................................................................................100 mA
Max. Output Current sunk by I/O port (GPIO )......................................................................................................100 mA
Note 1: Power Dissipation is calculated as follows: P
DIS = VDD x {IDD - IOH} + {(VDD-VOH) x IOH} + (VOL x IOL)
NOTICE: Stresses above those listed under "Maximum Ratings" may cause permanent damage to the device. This is a stress rating only and functional operation of the device at those or any other conditions above those indicated in the operation listings of this specification is not implied. Exposure to maximum rating conditions for extended periods may affect device reliability.
PIC12C5XX
DS40139D-page 78 Preliminary 1998 Microchip Technology Inc.
12.1 DC CHARACTERISTICS: PIC12C508A/509A (Commercial) PIC12C508A/509A (Industrial) PIC12C508A/509A (Extended)
DC Characteristics Power Supply Pins
Standard Operating Conditions (unless otherwise specified)
Operating Temperature 0°C TA +70°C (commercial)
–40°C T
A +85°C (industrial)
–40°C T
A +125°C (extended)
Characteristic Sym Min
Typ
(1)
Max Units Conditions
Supply Voltage V
DD 3.0 5.5 V FOSC = DC to 4 MHz (Commercial/
Industrial, Extended)
RAM Data Retention Voltage
(2)
VDR 1.5* V Device in SLEEP mode
V
DD Start Voltage to ensure
Power-on Reset
VPOR VSS V See section on Power-on Reset for details
V
DD Rise Rate to ensure
Power-on Reset
SVDD 0.05* V/ms See section on Power-on Reset for details
Supply Current
(3)
IDD
IWDT
— — — — —
— — —
0.6
0.6 15 19 19
3.75
3.75
3.75
1.4
1.4 27 35 35
8 9 4
mA mA
µA µA µA µA
µA µA
XT and EXTRC options (Note 4) F
OSC = 4 MHz, VDD = 5.5V
INTRC Option F
OSC = 4 MHz, VDD = 5.5V
LP O
PTION, Commercial Temperature
F
OSC = 32 kHz, VDD = 3.0V, WDT disabled
LP O
PTION, Industrial Temperature
F
OSC = 32 kHz, VDD = 3.0V, WDT disabled
LP O
PTION, Extended Temperature
F
OSC = 32 kHz, VDD = 3.0V, WDT disabled
V
DD = 3.0V, Commercial
V
DD = 3.0V, Industrial
V
DD = 3.0V, Extended
Power-Down Current
(5)
IPD
— —
0.25
0.25 2
4 5
18
µA µA µA
VDD = 3.0V, Commercial V
DD = 3.0V, Industrial
V
DD = 3.0V, Extended
* These parameters are characterized but not tested. Note 1: Data in the Typical (“Typ”) column is based on characterization results at 25°C. This data is for design guid-
ance only and is not tested.
2: This is the limit to which V
DD can be lowered in SLEEP mode without losing RAM data.
3: The supply current is mainly a function of the operating voltage and frequency. Other factors such as bus
loading, oscillator type, bus rate, internal code execution pattern, and temperature also have an impact on the current consumption.
a) The test conditions for all I
DD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tristated, pulled to V
ss, T0CKI = VDD, MCLR = VDD; WDT enabled/disabled as specified.
b) For standby current measurements, the conditions are the same, except that
the device is in SLEEP mode.
4: Does not include current through Rext. The current through the resistor can be estimated by the
formula: I
R = VDD/2Rext (mA) with Rext in kOhm.
5: The power down current in SLEEP mode does not depend on the oscillator type. Power down current is mea-
sured with the part in SLEEP mode, with all I/O pins in hi-impedance state and tied to V
DD or VSS.
1998 Microchip Technology Inc. Preliminary DS40139D-page 79
PIC12C5XX
12.2 DC CHARACTERISTICS: PIC12LC508A/509A (Commercial, Industrial)
DC Characteristics Power Supply Pins
Standard Operating Conditions (unless otherwise specified)
Operating Temperature 0°C T
A +70°C (commercial)
–40°C T
A +85°C (industrial)
Characteristic Sym Min
Typ
(1)
Max Units Conditions
Supply Voltage V
DD 2.5 5.5 V FOSC = DC to 4 MHz (Commercial/
Industrial)
RAM Data Retention Voltage
(2)
VDR 1.5* V Device in SLEEP mode
V
DD Start Voltage to ensure
Power-on Reset
VPOR VSS V See section on Power-on Reset for details
V
DD Rise Rate to ensure
Power-on Reset
SVDD 0.05* V/ms See section on Power-on Reset for details
Supply Current
(3)
IDD
IWDT
— — — —
TBD TBD TBD TBD
TBD
TBD TBD TBD TBD
TBD
mA mA
µA µA
µA
XT and EXTRC options (Note 4) F
OSC = 4 MHz, VDD = 2.5V
INTRC Option F
OSC = 4 MHz, VDD = 2.5V
LP O
PTION, Commercial Temperature
F
OSC = 32 kHz, VDD = 2.5V, WDT disabled
LP O
PTION, Industrial Temperature
F
OSC = 32 kHz, VDD = 2.5V, WDT disabled
Power-Down Current
(5)
IPD
——TBD
TBD
TBD TBDµAµA
VDD = 2.5V, Commercial V
DD = 2.5V, Industrial
* These parameters are characterized but not tested. Note 1: Data in the Typical (“Typ”) column is based on characterization results at 25°C. This data is for design guid-
ance only and is not tested.
2: This is the limit to which V
DD can be lowered in SLEEP mode without losing RAM data.
3: The supply current is mainly a function of the operating voltage and frequency. Other factors such as bus
loading, oscillator type, bus rate, internal code execution pattern, and temperature also have an impact on the current consumption.
a) The test conditions for all I
DD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tristated, pulled to V
ss, T0CKI = VDD, MCLR = VDD; WDT enabled/disabled as specified.
b) For standby current measurements, the conditions are the same, except that
the device is in SLEEP mode.
4: Does not include current through Rext. The current through the resistor can be estimated by the
formula: I
R = VDD/2Rext (mA) with Rext in kOhm.
5: The power down current in SLEEP mode does not depend on the oscillator type. Power down current is mea-
sured with the part in SLEEP mode, with all I/O pins in hi-impedance state and tied to V
DD or VSS.
PIC12C5XX
DS40139D-page 80 Preliminary 1998 Microchip Technology Inc.
12.3 DC CHARACTERISTICS: PIC12C508A/509A (Commercial, Industrial, Extended)
DC CHARACTERISTICS
Standard Operating Conditions (unless otherwise specified)
Operating temperature 0˚C T
A +70˚C (commercial)
–40˚C T
A +85˚C (industrial)
–40°C T
A +125˚C (extended)
Operating voltage V
DD range as described in DC spec Section 12.1 and
Section 12.2.
Param
No.
Characteristic Sym Min Typ†Max Units Conditions
Input Low Voltage
I/O ports V
IL
D030 with TTL buffer VSS - 0.5V V D031 with Schmitt Trigger buffer V
SS - 0.2VDD V
D032 MCLR
, GP2/T0CKI/AN2/INT
(in EXTRC mode)
VSS - 0.2VDD V
D033 OSC1 (in XT, HS and LP) V
SS - 0.3VDD V Note1
Input High Voltage
I/O ports V
IH -
D040 with TTL buffer 2.0 - V
DD V 4.5 VDD 5.5V
D040A 0.8V
DD - VDD V For VDD > 5.5V or VDD < 4.5V
D041 with Schmitt Trigger buffer 0.8V
DD - VDD V For entire VDD range
D042 MCLR
, GP2/T0CKI/AN2/INT 0.8VDD - VDD V
D042A OSC1 (XT, HS and LP) 0.7V
DD - VDD V Note1
D043 OSC1 (in EXTRC mode) 0.9V
DD - VDD V
D070 GPIO weak pull-up current I
PUR 50 250 400 µA VDD = 5V, VPIN = VSS
Input Leakage Current (Notes 2, 3)
D060 I/O ports I
IL - - +1 µA Vss VPIN VDD, Pin at hi-
impedance
D061 MCLR
, GP2/T0CKI - -
+
5
(5)
µA Vss VPIN VDD
D063 OSC1 - - +5 µA Vss VPIN ≤ VDD, XT, HS and LP
osc configuration
Output Low Voltage
D080 I/O ports/CLKOUT V
OL - - 0.6 V IOL = 8.5 mA, VDD = 4.5V,
–40°C to +85°C
D080A - - 0.6 V I
OL = 7.0 mA, VDD = 4.5V,
–40°C to +125°C
D083 OSC2 - - 0.6 V I
OL = 1.6 mA, VDD = 4.5V,
–40°C to +85°C
D083A - - 0.6 V I
OL = 1.2 mA, VDD = 4.5V,
–40°C to +125°C
† Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: In EXTRC oscillator configuration, the OSC1/CLKIN pin is a Schmitt Trigger input. It is not recommended that
the PIC12C5XX be driven with external clock in RC mode.
2: The leakage current on the MCLR
pin is strongly dependent on the applied voltage lev el. The specified levels
represent normal operating conditions. Higher leakage current may be measured at different input voltages.
3: Negative current is defined as coming out of the pin.
4: Extended operating range is Advance Information for this device.
5: When configured as external reset, the input leakage current is the weak pulll-up current of -10mA minimum.
This pull-up is weaker than the standard I/O pull-up.
1998 Microchip Technology Inc. Preliminary DS40139D-page 81
PIC12C5XX
Output High Voltage
D090 I/O ports/CLKOUT (Note 3) V
OH VDD - 0.7 - - V IOH = -3.0 mA, VDD = 4.5V,
–40°C to +85°C
D090A V
DD - 0.7 - - V IOH = -2.5 mA, VDD = 4.5V,
–40°C to +125°C
D092 OSC2 V
DD - 0.7 - - V IOH = -1.3 mA, VDD = 4.5V,
–40°C to +85°C
D092A V
DD - 0.7 - - V IOH = -1.0 mA, VDD = 4.5V,
–40°C to +125°C
Capacitive Loading Specs on Output Pins
D100 OSC2 pin C
OSC2 - - 15 pF In XT, HS and LP modes when
external clock is used to drive OSC1.
D101 All I/O pins and OSC2 C
IO - - 50 pF
DC CHARACTERISTICS
Standard Operating Conditions (unless otherwise specified)
Operating temperature 0˚C T
A +70˚C (commercial)
–40˚C T
A +85˚C (industrial)
–40°C T
A +125˚C (extended)
Operating voltage V
DD range as described in DC spec Section 12.1 and
Section 12.2.
Param
No.
Characteristic Sym Min Typ†Max Units Conditions
† Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: In EXTRC oscillator configuration, the OSC1/CLKIN pin is a Schmitt Trigger input. It is not recommended that
the PIC12C5XX be driven with external clock in RC mode.
2: The leakage current on the MCLR
pin is strongly dependent on the applied voltage lev el. The specified levels
represent normal operating conditions. Higher leakage current may be measured at different input voltages.
3: Negative current is defined as coming out of the pin.
4: Extended operating range is Advance Information for this device.
5: When configured as external reset, the input leakage current is the weak pulll-up current of -10mA minimum.
This pull-up is weaker than the standard I/O pull-up.
PIC12C5XX
DS40139D-page 82 Preliminary 1998 Microchip Technology Inc.
12.4 DC CHARACTERISTICS: PIC12LC508A/509A (Commercial, Industrial)
DC CHARACTERISTICS
Standard Operating Conditions (unless otherwise specified)
Operating temperature 0˚C T
A +70˚C (commercial)
–40˚C T
A +85˚C (industrial)
Operating voltage V
DD range as described in DC spec Section 12.1 and
Section 12.2.
Param
No.
Characteristic Sym Min Typ†Max Units Conditions
Input Low Voltage
I/O ports V
IL
D030 with TTL buffer VSS - 0.5V V D031 with Schmitt Trigger buffer V
SS - 0.2VDD V
D032 MCLR
, GP2/T0CKI/AN2/INT
(in EXTRC mode)
VSS - 0.2VDD V
D033 OSC1 (in XT, HS and LP) V
SS - 0.3VDD V Note1
Input High Voltage
I/O ports V
IH -
D040 with TTL buffer TBD - V
DD V 4.5 VDD 5.5V
D040A TBD - V
DD V For VDD > 5.5V or VDD < 4.5V
D041 with Schmitt Trigger buffer 0.8V
DD - VDD V For entire VDD range
D042 MCLR
, GP2/T0CKI/AN2/INT 0.8VDD - VDD V
D042A OSC1 (XT, HS and LP) 0.7V
DD - VDD V Note1
D043 OSC1 (in EXTRC mode) 0.9V
DD - VDD V
D070 GPIO weak pull-up current I
PUR 50 250 400 µA VDD = 5V, VPIN = VSS
Input Leakage Current (Notes 2, 3)
D060 I/O ports I
IL TBD TBD TBD µA Vss VPIN VDD, Pin at hi-
impedance
D061 MCLR
, GP2/T0CKI TBD TBD TBD µA Vss VPIN VDD
D063 OSC1 TBD TBD TBD µA Vss VPIN ≤ VDD, XT, HS and LP
osc configuration
Output Low Voltage
D080 I/O ports/CLKOUT V
OL - - TBD V IOL = 8.5 mA, VDD = 4.5V,
–40°C to +85°C
D080A - - 0.6 V I
OL = 7.0 mA, VDD = 4.5V,
–40°C to +125°C
D083 OSC2 - - 0.6 V I
OL = 1.6 mA, VDD = 4.5V,
–40°C to +85°C
D083A - - 0.6 V I
OL = 1.2 mA, VDD = 4.5V,
–40°C to +125°C
† Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: In EXTRC oscillator configuration, the OSC1/CLKIN pin is a Schmitt Trigger input. It is not recommended that
the PIC12C67X be driven with external clock in RC mode.
2: The leakage current on the MCLR
pin is strongly dependent on the applied voltage lev el. The specified levels
represent normal operating conditions. Higher leakage current may be measured at different input voltages.
3: Negative current is defined as coming out of the pin.
4: Extended operating range is Advance Information for this device.
5: When configured as external reset, the input leakage current is the weak pulll-up current of -10mA minimum.
This pull-up is weaker than the standard I/O pull-up.
1998 Microchip Technology Inc. Preliminary DS40139D-page 83
PIC12C5XX
Output High Voltage
D090 I/O ports/CLKOUT (Note 3) V
OH VDD - 0.7 - - V IOH = -3.0 mA, VDD = 4.5V,
–40°C to +85°C
D090A V
DD - 0.7 - - V IOH = -2.5 mA, VDD = 4.5V,
–40°C to +125°C
D092 OSC2 V
DD - 0.7 - - V IOH = -1.3 mA, VDD = 4.5V,
–40°C to +85°C
D092A V
DD - 0.7 - - V IOH = -1.0 mA, VDD = 4.5V,
–40°C to +125°C
Capacitive Loading Specs on Output Pins
D100 OSC2 pin C
OSC2 - - 15 pF In XT, HS and LP modes when
external clock is used to drive OSC1.
D101 All I/O pins and OSC2 C
IO - - 50 pF
DC CHARACTERISTICS
Standard Operating Conditions (unless otherwise specified)
Operating temperature 0˚C T
A +70˚C (commercial)
–40˚C T
A +85˚C (industrial)
Operating voltage V
DD range as described in DC spec Section 12.1 and
Section 12.2.
Param
No.
Characteristic Sym Min Typ†Max Units Conditions
† Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only
and are not tested.
Note 1: In EXTRC oscillator configuration, the OSC1/CLKIN pin is a Schmitt Trigger input. It is not recommended that
the PIC12C67X be driven with external clock in RC mode.
2: The leakage current on the MCLR
pin is strongly dependent on the applied voltage lev el. The specified levels
represent normal operating conditions. Higher leakage current may be measured at different input voltages.
3: Negative current is defined as coming out of the pin.
4: Extended operating range is Advance Information for this device.
5: When configured as external reset, the input leakage current is the weak pulll-up current of -10mA minimum.
This pull-up is weaker than the standard I/O pull-up.
PIC12C5XX
DS40139D-page 84 Preliminary 1998 Microchip Technology Inc.
TABLE 12-1: PULL-UP RESISTOR RANGES - PIC12C508A/C509A
VDD (Volts) Temperature (°C) Min Typ Max Units
GP0/GP1
2.5 –40 38K 42K 63K 25 42K 48K 63K 85 42K 49K 63K
125 50K 55K 63K
5.5 –40 15K 17K 20K 25 18K 20K 23K 85 19K 22K 25K
125 22K 24K 28K
GP3
2.5 –40 285K 346K 417K 25 343K 414K 532K 85 368K 457K 532K
125 431K 504K 593K
5.5 –40 247K 292K 360K 25 288K 341K 437K 85 306K 371K 448K
125 351K 407K 500K
* These parameters are characterized but not tested.
1998 Microchip Technology Inc. Preliminary DS40139D-page 85
PIC12C5XX
12.5 Timing Parameter Symbology and Load Conditions - PIC12C508A/C509A
The timing parameter symbols have been created following one of the following formats:
1. TppS2ppS
2. TppS
T
F Frequency T Time Lowercase subscripts (pp) and their meanings:
pp
2 to mc MCLR ck CLKOUT osc oscillator cy cycle time os OSC1 drt device reset timer t0 T0CKI io I/O port wdt watchdog timer Uppercase letters and their meanings:
S
F Fall P Period H High R Rise I Invalid (Hi-impedance) V Valid L Low Z Hi-impedance
FIGURE 12-1: LOAD CONDITIONS - PIC12C508A/C509A
CL
VSS
Pin
C
L = 50 pF for all pins except OSC2
15 pF for OSC2 in XT, HS or LP
modes when external clock is used to drive OSC1
PIC12C5XX
DS40139D-page 86 Preliminary 1998 Microchip Technology Inc.
12.6 Timing Diagrams and Specifications FIGURE 12-2: EXTERNAL CLOCK TIMING - PIC12C508A/C509A
TABLE 12-2: EXTERNAL CLOCK TIMING REQUIREMENTS - PIC12C508A/C509A
AC Characteristics Standard Operating Conditions (unless otherwise specified)
Operating Temperature 0°C T
A +70°C (commercial),
–40°C T
A +85°C (industrial),
–40°C T
A +125°C (extended)
Operating Voltage V
DD range is described in Section 12.1
Parameter
No.
Sym Characteristic Min
Typ
(1)
Max Units Conditions
FOSC
External CLKIN Frequency
(2)
DC 4 MHz XT osc mode DC 200 kHz LP osc mode
Oscillator Frequency
(2)
DC 4 MHz EXTRC osc mode
0.1 4 MHz XT osc mode DC 200 kHz LP osc mode
1 T
OSC
External CLKIN Period
(2)
250 ns XT osc mode
5 ms LP osc mode
Oscillator Period
(2)
250 ns EXTRC osc mode 250 10,000 ns XT osc mode
5 ms LP osc mode
2 Tcy
Instruction Cycle Time
(3)
4/FOSC
3 TosL, TosH Clock in (OSC1) Low or High Time 50* ns XT oscillator
2* ms LP oscillator
4 TosR, TosF Clock in (OSC1) Rise or Fall Time 25* ns XT oscillator
50* ns LP oscillator
* These parameters are characterized but not tested.
Note 1: Data in the Typical (“Typ”) column is at 5V, 25°C unless otherwise stated. These parameters are for design
guidance only and are not tested.
2: All specified values are based on characterization data for that particular oscillator type under standard oper-
ating conditions with the device executing code. Exceeding these specified limits may result in an unstable oscillator operation and/or higher than expected current consumption. When an external clock input is used, the “max” cycle time limit is “DC” (no clock) for all devices.
3: Instruction cycle period (T
CY) equals four times the input oscillator time base period.
OSC1
Q4
Q1 Q2
Q3 Q4 Q1
1 3 3
4 4
2
1998 Microchip Technology Inc. Preliminary DS40139D-page 87
PIC12C5XX
TABLE 12-3: CALIBRATED INTERNAL RC FREQUENCIES - PIC12C508A/C509A
AC Characteristics Standard Operating Conditions (unless otherwise specified)
Operating Temperature 0°C T
A +70°C (commercial),
–40°C T
A +85°C (industrial),
–40°C T
A +125°C (extended)
Operating Voltage V
DD range is described in Section 10.1
Parameter
No.
Sym Characteristic Min*
Typ
(1)
Max* Units Conditions
Internal Calibrated RC Frequency TBD 4.00 TBD MHz VDD = 5.0V
Internal Calibrated RC Frequency
TBD 4.00 TBD MHz V
DD = 2.5V
* These parameters are characterized but not tested.
Note 1: Data in the Typical (“Typ”) column is at 5V, 25°C unless otherwise stated. These parameters are for design
guidance only and are not tested.
PIC12C5XX
DS40139D-page 88 Preliminary 1998 Microchip Technology Inc.
FIGURE 12-3: I/O TIMING - PIC12C508A/C509A
TABLE 12-4: TIMING REQUIREMENTS - PIC12C508A/C509A
AC Characteristics Standard Operating Conditions (unless otherwise specified)
Operating Temperature 0°C T
A +70°C (commercial)
–40°C T
A +85°C (industrial)
–40°C T
A +125°C (extended)
Operating Voltage V
DD range is described in Section 12.1
Parameter
No. Sym Characteristic Min Typ
(1)
Max Units
17
TosH2ioV
OSC1 (Q1 cycle) to Port out valid
(3)
100* ns
18
TosH2ioI OSC1 (Q2 cycle) to Port input invalid
(I/O in hold time)
TBD ns
19
TioV2osH Port input valid to OSC1
(I/O in setup time)
TBD ns
20
TioR
Port output rise time
(3)
10 25** ns
21
TioF
Port output fall time
(3)
10 25** ns
* These parameters are characterized but not tested.
** These parameters are design targets and are not tested. No characterization data available at this time.
Note 1: Data in the Typical (“Typ”) column is at 5V, 25˚C unless otherwise stated. These parameters are for design
guidance only and are not tested. 2: Measurements are taken in EXTRC mode. 3: See Figure 12-1 for loading conditions.
OSC1
I/O Pin
(input)
I/O Pin
(output)
Q4
Q1
Q2 Q3
17
20, 21
18
Old Value
New Value
Note: All tests must be done with specified capacitive loads (see data sheet) 50 pF on I/O pins and CLKOUT.
19
1998 Microchip Technology Inc. Preliminary DS40139D-page 89
PIC12C5XX
FIGURE 12-4: RESET, WATCHDOG TIMER, AND DEVICE RESET TIMER TIMING -
PIC12C508A/C509A
TABLE 12-5: RESET, WATCHDOG TIMER, AND DEVICE RESET TIMER - PIC12C508A/C509A
AC Characteristics Standard Operating Conditions (unless otherwise specified)
Operating Temperature 0°C T
A +70°C (commercial)
–40°C T
A +85°C (industrial)
–40°C T
A +125°C (extended)
Operating Voltage V
DD range is described in Section 12.1
Parameter
No. Sym Characteristic Min Typ
(1)
Max Units Conditions
30
TmcL MCLR Pulse Width (low) 2000* ns VDD = 5 V
31
Twdt Watchdog Timer Time-out Period
(No Prescaler)
9* 18* 30* ms VDD = 5 V (Commercial)
32
TDRT Device Reset Timer Period
(2)
9* 18* 30* ms VDD = 5 V (Commercial)
34
TioZ I/O Hi-impedance from MCLR Low 2000* ns
* These parameters are characterized but not tested.
Note 1: Data in the Typical (“Typ”) column is at 5V, 25°C unless otherwise stated. These parameters are for design
guidance only and are not tested.
VDD
MCLR
Internal
POR
DRT
Timeout
Internal
RESET
Watchdog
Timer
RESET
32
31
34
I/O pin
32
32
34
(Note 1)
Note 1: I/O pins must be taken out of hi-impedance mode by enabling the output drivers in software.
30
(Note 2)
2: Runs in MCLR or WDT reset only in XT and LP modes.
PIC12C5XX
DS40139D-page 90 Preliminary 1998 Microchip Technology Inc.
TABLE 12-6: DRT (DEVICE RESET TIMER PERIOD) - PIC12C508A/C509A
FIGURE 12-5: TIMER0 CLOCK TIMINGS - PIC12C508A/C509A
TABLE 12-7: TIMER0 CLOCK REQUIREMENTS - PIC12C508A/C509A
Oscillator Configuration POR Reset Subsequent Resets
IntRC & ExtRC 18 ms (typical) 300 µs (typical) XT & LP 18 ms (typical) 18 ms (typical)
AC Characteristics Standard Operating Conditions (unless otherwise specified)
Operating Temperature 0°C T
A +70°C (commercial)
–40°C T
A +85°C (industrial)
–40°C T
A +125°C (extended)
Operating Voltage V
DD range is described in Section 12.1.
Parameter
No.
Sym Characteristic Min Typ
(1)
Max Units Conditions
40 Tt0H T0CKI High Pulse Width - No Prescaler 0.5 TCY + 20* ns
- With Prescaler 10* ns
41 Tt0L T0CKI Low Pulse Width - No Prescaler 0.5 TCY + 20* ns
- With Prescaler 10* ns
42 Tt0P T0CKI Period 20 or TCY + 40*
N
ns Whichever is greater.
N = Prescale Value
(1, 2, 4,..., 256)
* These parameters are characterized but not tested.
Note 1: Data in the Typical (“Typ”) column is at 5V, 25˚C unless otherwise stated. These parameters are for design guidance only
and are not tested.
T0CKI
40 41
42
1998 Microchip Technology Inc. Preliminary DS40139D-page 91
PIC12C5XX
13.0 DC AND AC CHARACTERISTICS - PIC12C508A/PIC12C509A/ PIC12LC508A/PIC12LC509A
The graphs and tables provided in this section are for design guidance and are not tested. In some graphs or tables the data presented are outside specified operating range (e.g., outside specified V
DD range). This is for information
only and devices will operate properly only within the specified range. The data presented in this section is a statistical summary of data collected on units from different lots over a period of
time. “Typical” represents the mean of the distribution while “max” or “min” represents (mean + 3σ) and (mean – 3σ) respectively, where σ is standard deviation.
FIGURE 13-1: CALIBRATED INTERNAL RC FREQUENCY RANGE VS. TEMPERATURE (VDD = 5.0V)
(INTERNAL RC IS CALIBRATED TO 25°C, 5.0V)
FIGURE 13-2: CALIBRATED INTERNAL RC FREQUENCY RANGE VS. TEMPERATURE (V
DD = 2.5V)
(INTERNAL RC IS CALIBRATED TO 25°C, 5.0V)
Not available at this time.
Not available at this time.
PIC12C5XX
DS40139D-page 92 Preliminary 1998 Microchip Technology Inc.
TABLE 13-1: DYNAMIC IDD (TYPICAL) - WDT ENABLED, 25°C
Oscillator Frequency VDD =3.0V VDD = 5.5V
External RC 4 MHz 300 µA* 620 µA* Internal RC 4 MHz 520 µA 1.1 mA XT 4 MHz 300 µA 775 µA LP 32 KHz 10 µA 37 µA *Does not include current through external R&C.
FIGURE 13-3: WDT TIMER TIME-OUT
PERIOD vs. VDD
50
45
40
35
30
25
20
15
10
5
2 3 4 5 6 7
V
DD (Volts)
WDT period (mS)
Max +125°C
Max +85°C
Typ +25°C
MIn –40°C
FIGURE 13-4: SHORT DRT PERIOD VS. VDD
1000
900
800
700
600
500
400
300
200
100
2 3 4 5 6 7
V
DD (Volts)
WDT period (µs)
Max +125°C
Max +85°C
Typ +25°C
MIn –40°C
1998 Microchip Technology Inc. Preliminary DS40139D-page 93
PIC12C5XX
FIGURE 13-5: IOH vs. VOH, VDD = 2.5 V
FIGURE 13-6: IOH vs. VOH, VDD = 3.5 V
VOH (Volts)
IOH (mA)
1.5 2.0 2.5 3.0 3.5
0
-5
-10
-15
-20
-25
-30
TBD
VOH (Volts)
IOH (mA)
1.5 2.0 2.5 3.0 3.5
0
-5
-10
-15
-20
-25
-30
Max –40°C
Typ +25°C
Min +85°C
Min +125°C
FIGURE 13-7: IOL vs. VOL, VDD = 2.5 V
FIGURE 13-8: I
OL vs. VOL, VDD = 3.5 V
25
20
15
10
5
0
500.0m 750.0m 1.0 V
OL (Volts)
IOL (mA)
0
30
35
TBD
25
20
15
10
5
0
500.0m 750.0m 1.0 V
OL (Volts)
IOL (mA)
Min +85°C
Max –40°C
Typ +25°C
0
Min +125°C
30
35
PIC12C5XX
DS40139D-page 94 Preliminary 1998 Microchip Technology Inc.
FIGURE 13-9: IOH vs. VOH, VDD = 5.5 V
3.5 4.0 4.5
VOH (Volts)
IOH (mA)
5.0 5.5
0
-5
-10
-15
-20
-25
-30
Min +125°C
Max –40°C
Typ +25°C
Min +85°C
FIGURE 13-10: IOL vs. VOL, VDD = 5.5 V
50
40
30
20
10
0
500.0m 750.0m 1.0 V
OL (Volts)
IOL (mA)
250.0m
Min +85°C
Max –40°C
Typ +25°C
Min +125°C
1998 Microchip Technology Inc. DS40139D-page 95
PIC12C5XX
14.0 PACKAGING INFORMATION
14.1 Package Marking Information
Legend: MM...M Microchip part number information
XX...X Customer specific information* AA Year code (last 2 digits of calendar year) BB Week code (week of January 1 is week ‘01’) C Facility code of the plant at which wafer is manufactured
O = Outside Vendor C = 5” Line S = 6” Line
H = 8” Line D Mask revision number E Assembly code of the plant or country of origin in which
part was assembled
Note: In the event the full Microchip part number cannot be marked on one line, it will
be carried over to the next line thus limiting the number of available characters for customer specific information.
* Standard OTP marking consists of Microchip part number, year code, week code, facility code, mask
rev#, and assembly code. For OTP marking beyond this, certain price adders apply. Please check with your Microchip Sales Office. For QTP devices, any special marking adders are included in QTP price.
XXXXXXXX XXXXXCDE
AABB
8-Lead PDIP (300 mil)
Example
8-Lead SOIC (208 mil)
XXXXXXX AABBCDE
XXXXXXX
8-Lead Windowed Ceramic Side Brazed (300 mil)
XXXXXX
XXX
Example
Example
12C508A 04I/PSAZ
9825
12C508A 9824SAZ
04I/SM
12C508A
JW
8-Lead SOIC (150 mil)
XXXXXXX
Example
XXXX
C508A
9825
PIC12C5XX
DS40139D-page 96 1998 Microchip Technology Inc.
Package Type: K04-018 8-Lead Plastic Dual In-line (P) – 300 mil
* Controlling Parameter.
Dimension “B1” does not include dam-bar protrusions. Dam-bar protrusions shall not exceed 0.003” (0.076 mm) per side or 0.006” (0.152 mm) more than dimension “B1.”
Dimensions “D” and “E” do not include mold flash or protrusions. Mold flash or protrusions shall not exceed 0.010” (0.254 mm) per side or 0.020” (0.508 mm) more than dimensions “D” or “E.”
0.310
0.267
0.245
0.355
0.120
0.005
0.060
0.140
0.006
0.000
0.055
0.014
Mold Draft Angle Bottom
Mold Draft Angle Top
Overall Row Spacing
Radius to Radius Width
Molded Package Width
Tip to Seating Plane
Base to Seating Plane
Top of Lead to Seating Plane
Top to Seating Plane
Upper Lead Width
Lower Lead Width
PCB Row Spacing
Package Length
Lead Thickness
Shoulder Radius
Number of Pins Pitch
eB
β
α
L
E1
E
D
A2
A1
A
B B1
R c
n p
Dimension Limits
Units
MIN
0.3800.342
5
5
10
10
15
15
0.130
0.280
0.250
0.370
0.020
0.080
0.150
0.018
0.012
0.005
0.060
0.100
0.300 8
0.292
0.260
0.385
0.140
0.035
0.100
0.160
0.015
0.010
0.065
0.022
9.658.677.87
5
5
10
10
15
15
7.10
6.35
9.40
3.30
0.51
2.03
3.81
0.29
0.13
1.52
0.46
2.54
7.62
3.05
6.78
6.22
9.02
0.13
1.52
3.56
0.36
0.20
0.00
1.40
3.56
7.42
6.60
9.78
0.89
2.54
4.06
8
0.56
0.38
0.25
1.65
MINNOM
INCHES*
MAX
MILLIMETERS
NOM MAX
n
1
2
R
D
E
c
β
eB
E1
α
p
A1
L
A
A2
B
B1
1998 Microchip Technology Inc. DS40139D-page 97
PIC12C5XX
Package Type: K04-057 8-Lead Plastic Small Outline (SN) – Narrow, 150 mil
MINDimension Limits
Mold Draft Angle Bottom
Mold Draft Angle Top
Lower Lead Width
Radius Centerline
Gull Wing Radius
Shoulder Radius
Chamfer Distance
Outside Dimension
Molded Package Width
Molded Package Length
Shoulder Height
Overall Pack. Height
Lead Thickness
Foot Angle
Foot Length
Standoff
Number of Pins
Pitch
β
α
c B
φ
X
A2
A1
A
n
p
E
R2
L1
L
R1
E1
D
Units
MAXNOMMINMAXNOM
8
12
12
0.017
0.009
0 0
0.014
0.008
0.020
0.010
15 15
0.005
0.016
0.005
0.005
0.015
0.237
0.154
0.193
0.007
0.035
0.061
0.050
0.150
0.005
0.000
0.011 0
0.005
0.010
0.229
0.189
0.004
0.027
0.054
0.157
0.010
0.021
0.010
0.010
0.020
0.244
4 8
0.196
0.010
0.044
0.069
8
0.36
0.19
0 0
12 12
0.43
0.22
15 15
0.51
0.25
3.81
0.00
0.28
0.13
0.13
0.25
5.82
0
4.80
0.10
0.69
1.37
3.993.90
0.13
4
0.13
0.41
0.38
0.13
6.01
0.25
0.25
0.53
0.51
0.25
6.20
0.18
4.89
0.90
8
1.56
1.27
0.25
4.98
1.11
1.75
INCHES* MILLIMETERS
n 1
2
R2
R1
D
p
B
E1
E
L1
X
L
β
c
45
°
φ
A1
α
A
A2
*
Controlling Parameter.
Dimension “B” does not include dam-bar protrusions. Dam-bar protrusions shall not exceed 0.003” (0.076 mm) per side or 0.006” (0.152 mm) more than dimension “B.”
Dimensions “D” and “E” do not include mold flash or protrusions. Mold flash or protrusions shall not exceed 0.010” (0.254 mm) per side or 0.020” (0.508 mm) more than dimensions “D” or “E.”
PIC12C5XX
DS40139D-page 98 1998 Microchip Technology Inc.
Package Type: K04-056 8-Lead Plastic Small Outline (SM) – Medium, 208 mil
MIN
Mold Draft Angle Bottom
Mold Draft Angle Top
Lower Lead Width
Radius Centerline
Gull Wing Radius
Shoulder Radius
Outside Dimension
Molded Package Width
Molded Package Length
Shoulder Height
Overall Pack. Height
Lead Thickness
Foot Angle
Foot Length
Standoff
Number of Pins
Pitch
c
β
α
B
φ
A2
A1
A
n
p
R2
L1
L
R1
E1
D
E
Dimension Limits
Units
8
0.0100.0090.008
12
12
0.017
0
0.014 0
0.020
15
15
0.015
0.016
0.005
0.005
0.313
0.208
0.205
0.005
0.042
0.074
0.050
0.005
0.010
0.011 0
0.005
0.300
0.037
0.203
0.200
0.002
0.070
0.020
0.021
0.010
0.010
0.325
4 8
0.213
0.210
0.009
0.048
0.079
8
0.250.220.19
0.36
0
0
12
12
0.43
15
15
0.51
0.25
0.28
0.13
0.13
7.62
0
5.16
5.08
0.05
0.94
1.78
0.13
4
0.38
0.41
0.13
7.94
0.25
0.51
0.53
0.25
8.26
1.08
5.21
5.28
0.14
8
1.89
1.27
1.21
5.33
5.41
0.22
2.00
NOM
INCHES*
MAX NOM
MILLIMETERS
MIN MAX
n 1
2
R2
R1
α
A1
A
A2
L1
L
c
β
φ
D
p
B
E1
E
*
Controlling Parameter.
Dimension “B” does not include dam-bar protrusions. Dam-bar protrusions shall not exceed 0.003” (0.076 mm) per side or 0.006” (0.152 mm) more than dimension “B.”
Dimensions “D” and “E” do not include mold flash or protrusions. Mold flash or protrusions shall not exceed 0.010” (0.254 mm) per side or 0.020” (0.508 mm) more than dimensions “D” or “E.”
1998 Microchip Technology Inc. DS40139D-page 99
PIC12C5XX
Package Type: K04-084 8-Lead Ceramic Side Brazed Dual In-line with Window (JW) – 300 mil
n
1
2
0.260
0.440
0.161
0.310
0.280
0.510
0.130
0.025
0.103
0.145
0.008
0.050
0.016
0.098
MIN
Window Diameter
Overall Row Spacing
Package Length
Tip to Seating Plane
Base to Seating Plane
Top of Body to Seating Plane
Top to Seating Plane
Upper Lead Width
Lower Lead Width
PCB Row Spacing
Dimension Limits
Lid Length Lid Width
Package Width
Lead Thickness
Number of Pins Pitch
Units
T U
D
W
eB
E
A2
A1
L
B
A
c
B1
p
n
0.450
0.270
0.520
0.166
0.338
0.290
0.140
0.035
0.123
0.460
0.280
0.171
0.365
0.300
0.530
0.150
0.045
0.143
8
NOM
0.018
0.165
0.010
0.055
0.100
0.300
MAX
0.185
0.012
0.060
0.020
0.102
6.86
11.43
4.22
8.57
7.37
13.21
3.56
0.89
3.12
11.18
6.60
12.95
4.09
7.87
7.11
3.30
0.64
2.62
11.68
7.11
13.46
4.34
9.27
7.62
3.81
1.14
3.63
4.19
0.25
1.40
0.46
2.54
7.62
NOM
MILLIMETERS
MIN
0.41
3.68
0.20
1.27
2.49
MAX
8
0.51
4.70
0.30
1.52
2.59
D
T
E
U
W
c
eB
L
A1
B
B1
A
A2
p
INCHES*
* Controlling Parameter.
PIC12C5XX
DS40139D-page 100 1998 Microchip Technology Inc.
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