MICROCHIP PIC12C5XX User Manual

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PIC12C5XX

8-Pin, 8-Bit CMOS Microcontroller

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

Device EPROM RAM

PIC12C508 512 x 12 25 PIC12C508A 512 x 12 25 PIC12C509 1024 x 12 41 PIC12C509A 1024 x 12 41

• 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

• Selectable oscillator options:

- INTRC: Internal 4 MHz RC oscillator

- 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

PIC12C508(A

VDD

GP5/OSC1/CLKIN

GP4/OSC2

GP3/MCLR

/VPP

PIC12C509(A)

)

VSS GP0 GP1 GP2/T0CKI

1998 Microchip Technology Inc. DS40139D-page 1

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PIC12C5XX

Device Differences

Device

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

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.

Voltage

Range

Oscillator

Calibration

(Bits)

Process

Technology

(Microns)

DS40139D-page 2

1998 Microchip Technology Inc.

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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:

• Microchip’s Worldwide Web site; http://www.microchip.com

• Your local Microchip sales ofﬁce (see last page)

• 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 information that is missing or appears in error, please:

• Fill out and mail in the reader response form in the back of this data sheet.

• E-mail us at webmaster@microchip.com.

We appreciate your assistance in making this a better document.

1998 Microchip Technology Inc. DS40139D-page 3

PIC12C5XX

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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.

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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).

DS40139D-page 4

1998 Microchip Technology Inc.

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TABLE 1-1: PIC12CXXX & PIC12CEXXX FAMILY OF DEVICES

PIC12C509(A) PIC12CE518 PIC12CE519 PIC12C671 PIC12C672 PIC12CE673 PIC12CE674

8-pin DIP, JW, SOIC

Clock

Memory

Peripherals

Features

PIC12C508(A)

Maximum Frequency of Operation (MHz)

EPROM Program Memory

RAM Data Memory (bytes)

EEPROM Data Memory (bytes)

Timer Module(s)

A/D Converter (8-bit) Channels

Wake-up from SLEEP on pin change

Interrupt Sources

I/O Pins 5 5 5 5 5 5 5 5 Input Pins 1 1 1 1 1 1 1 1 Internal

Pull-ups In-Circuit

Serial Programming

Number of Instructions

Packages 8-pin DIP,

4 4 4 4 10 10 10 10

512 x 12 1024 x 12 512 x 12 1024 x 12 1024 x 14 2048 x 14 1024 x 14 2048 x 14

25 41 25 41 128 128

— — 16 16 — —

TMR0 TMR0 TMR0 TMR0 TMR0 TMR0 TMR0 TMR0

— — — — 4 4 4 4

Yes Yes Yes Yes Yes Yes Yes Yes

— — 4 4 4 4

Yes Yes Yes Yes Yes Yes Yes Yes

33 33 33 33 35 35 35 35

JW, SOIC

PIC12C5XX

128 128

16 16

8-pin DIP, JW, SOIC

8-pin DIP, JW8-pin DIP,

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.

1998 Microchip Technology Inc. DS40139D-page 5

PIC12C5XX

NOTES:

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DS40139D-page 6

1998 Microchip Technology Inc.

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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

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.

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.

Microchip's PICSTART grammers all support programming of the PIC12C5XX. Third party programmers also are available; ref er to the

Microchip

Third Party Guide

le Devices



PLUS and PRO MATE

for a list of sources.



pro-

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

Production (SQTP

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.

ed Quick-Turnaround

vices

) De

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.

1998 Microchip Technology Inc. DS40139D-page 7

PIC12C5XX

NOTES:

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DS40139D-page 8

1998 Microchip Technology Inc.

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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.

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 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.

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 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.

ow and digit borrow out bit,

1998 Microchip Technology Inc. DS40139D-page 9

PIC12C5XX

FIGURE 3-1: PIC12C5XX BLOCK DIAGRAM



OSC1/CLKIN

OSC2

Program

Bus

EPROM

512 x 12 or

1024 x 12

Program

Memory

Instruction reg

Instruction

Decode &

Control

Timing

Generation

Internal RC

OSC

Program Counter

STACK1 STACK2

Direct Addr

Device Reset

Timer

Power-on

Reset

Watchdog

Timer

MCLR

Vdd, Vss

RAM Addr

Data Bus

Addr MUX

RAM

25 x 8 or

41 x 8

File

Registers

5-7

FSR reg

STATUS reg

MUX

ALU

W reg

Timer0

Indirect

Addr

GPIO

GP0 GP1 GP2/T0CKI GP3/MCLR/Vpp GP4/OSC2 GP5/OSC1/CLKIN

DS40139D-page 10

1998 Microchip Technology Inc.

TABLE 3-1: PIC12C5XX PINOUT DESCRIPTION



PIC12C5XX

Name

GP0 7 7 I/O TTL/ST Bi-directional I/O port/ serial programming data. Can

GP1 6 6 I/O TTL/ST Bi-directional I/O port/ serial programming clock. Can

GP2/T0CKI 5 5 I/O ST Bi-directional I/O port. Can be conﬁgured as T0CKI. GP3/MCLR

GP4/OSC2 3 3 I/O TTL Bi-directional I/O port/oscillator crystal output. Con-

GP5/OSC1/CLKIN 2 2 I/O TTL/ST Bidirectional IO port/oscillator crystal input/external

DD SS

Legend: I = input, O = output, I/O = input/output, P = power, — = not used, TTL = TTL input, ST = Schmitt Trigger input

DIP

Pin #

SOIC Pin #

4 4 I TTL/ST Input port/master clear (reset) input/programming volt-

1 1 P — Positive supply for logic and I/O pins 8 8 P — Ground reference for logic and I/O pins

I/O/P Type

Buffer

Type

Description

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.

age input. When conﬁgured as MCLR active low reset to the device. Voltage on MCLR must not exceed V 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 mode.

nections to crystal or resonator in crystal oscillator mode (XT and LP modes only, GPIO in other modes).

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.

during normal device operation

, this pin is an

. ST when in MCLR

1998 Microchip Technology Inc. DS40139D-page 11

PIC12C5XX



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

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)

EXAMPLE 3-1: INSTRUCTION PIPELINE FLOW

1. MOVLW 03H

2. MOVWF GPIO

3. CALL SUB_1

4. BSF GPIO, BIT1

Fetch 1 Execute 1

Fetch 2 Execute 2

Q2 Q3 Q4

Execute INST (PC) Fetch INST (PC+2)

Q2 Q3 Q4

Execute INST (PC+1)

Fetch 3 Execute 3

Fetch 4 Flush

Fetch SUB_1 Execute SUB_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.

DS40139D-page 12

1998 Microchip Technology Inc.



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

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.

ogram Memory Organization

FIGURE 4-1: PROGRAM MEMORY MAP

AND STACK FOR THE PIC12C5XX

PC<11:0>

CALL, RETLW

Stack Level 1 Stack Level 2

Reset Vector (note 1)

On-chip Program

Memory

512 Word (PIC12C508(A))

Space

User Memory

On-chip Program

Memory

1024 Word (PIC12C509(A))

0000h

01FFh 0200h

03FFh 0400h

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.

7FFh

1998 Microchip Technology Inc. DS40139D-page 13

PIC12C5XX



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

(1)

00h 01h 02h 03h 04h 05h 06h 07h

1Fh

Note 1: Not a physical register. See Section 4.8

INDF

TMR0

PCL

STATUS

FSR

OSCCAL

GPIO

General

Purpose

Registers

FIGURE 4-3: PIC12C509(A) REGISTER FILE MAP

FSR<6:5> 00 01

File Address

00h 01h 02h 03h 04h 05h 06h

07h

0Fh

10h

1Fh

Note 1: Not a physical register. See Section 4.8

(1)

INDF

TMR0

PCL

STATUS

FSR

OSCCAL

GPIO

General Purpose Registers

Bank 0 Bank 1

20h

Addresses map back to addresses in Bank 0.

2Fh

30h

General Purpose Registers

3Fh

DS40139D-page 14

1998 Microchip Technology Inc.

PIC12C5XX

4.2.2 SPECIAL FUNCTION REGISTERS

The special registers can be classiﬁed into two sets. The special function registers associated with the

The Special Function Registers (SFRs) are registers used by the CPU and peripheral functions to control the operation of the device (Table 4-1).

“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

N/A TRIS I/O control registers

N/A OPTION 00h INDF Uses contents of FSR to address data memory (not a physical register)

01h TMR0 8-bit real-time clock/counter

(1)

02h 03h STATUS GPWUF — PA0 TO PD Z DC C

PCL Low order 8 bits of PC

Contains control bits to conﬁgure Timer0, Timer0/WDT prescaler, wake-up on change, and weak pull-ups

Value on

Power-On

Reset

--11 1111 --11 1111

1111 1111 1111 1111 xxxx xxxx uuuu uuuu

xxxx xxxx uuuu uuuu 1111 1111 1111 1111 0001 1xxx q00q quuu

Value on All Other

(2)

Resets

(3)

 1998 Microchip Technology Inc. DS40139D-page 15

PIC12C5XX

4.3 STATUS Register

For example, CLRF STATUS will clear the upper three bits and set the Z bit. This leaves the 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

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.

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.

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

bit7 6 5 4 3 2 1 bit0 bit 7: GPWUF: GPIO reset bit

bit 6: Unimplemented bit 5: PA0: Program page preselect bits

bit 4: TO: Time-out bit

bit 3: PD: Power-down bit

bit 2: Z: Zero bit

bit 1: DC: Digit carry/borrow bit (for ADDWF and SUBWF instructions)

bit 0: C: Carry/borrow bit (for ADDWF, SUBWF and RRF, RLF instructions)

—

1 = Reset due to wake-up from SLEEP on pin change 0 = After power up or other reset

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.

1 = After power-up, CLRWDT instruction, or SLEEP instruction 0 = A WDT time-out occurred

1 = After power-up or by the CLRWDT instruction 0 = By execution of the SLEEP instruction

1 = The result of an arithmetic or logic operation is zero 0 = The result of an arithmetic or logic operation is not zero

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

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

PA0 TO PD Z DC C R = Readable bit

W = Writable bit

- n = Value at POR reset

DS40139D-page 16  1998 Microchip Technology Inc.

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

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 overrides OPTION control of GPPU

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

bit7 6 5 4 3 2 1 bit0

bit 7: GPWU

bit 6: GPPU: Enable weak pull-ups (GP0, GP1, GP3)

bit 5: T0CS: Timer0 clock source select bit

bit 4: T0SE: Timer0 source edge select bit

bit 3: PSA: Prescaler assignment bit

bit 2-0: PS2:PS0: Prescaler rate select bits

: Enable wake-up on pin change (GP0, GP1, GP3) 1 = Disabled 0 = Enabled

1 = Disabled 0 = Enabled

1 = Transition on T0CKI pin 0 = Transition on internal instruction cycle clock, Fosc/4

1 = Increment on high to low transition on the T0CKI pin 0 = Increment on low to high transition on the T0CKI pin

1 = Prescaler assigned to the WDT 0 = Prescaler assigned to Timer0

Bit Value Timer0 Rate WDT Rate

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

U = Unimplemented bit

- n = Value at POR reset Reference Table 4-1 for other resets.

and GPWU.

 1998 Microchip Technology Inc. DS40139D-page 17

PIC12C5XX

4.5 OSCCAL Register

The Oscillator Calibration (OSCCAL) register is used to calibrate the internal 4 MHz oscillator. It contains f our 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)

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

bit7 bit0

bit 7-4: CAL<3:0>: Calibration bit 3-0: Unimplemented: Read as '0'

FIGURE 4-7: OSCCAL REGISTER (ADDRESS 8Fh)PIC12C508A/C509A

W = Writable bit U = Unimplemented bit,

read as ‘0’

- n = Value at POR reset

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

bit7 bit0

bit 7-2: CAL<5:0>: Calibration bit 1-0: Unimplemented: Read as '0'

W = Writable bit U = Unimplemented bit,

read as ‘0’

- n = Value at POR reset

DS40139D-page 18  1998 Microchip Technology Inc.

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.

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).

FIGURE 4-8: LOADING OF PC

BRANCH INSTRUCTIONS -

PIC12C5XX

GOTO Instruction

7 0

CALL or Modify PCL Instruction

8 7 0

910

PCL

Instruction Word

PA0

STATUS

8 7 0

910

PCL

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.

push

A CALL instruction will 1 into stack 2 and then push the current program counter value, incremented by one , into stac k le vel 1. If more than two sequential CALL’s are executed, only the most recent two return addresses are stored.

A RETLW instruction will 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.

the current value of stack

pop

the contents of stack level

Instruction Word

Reset to ‘0’

PA0

7 0

STATUS

 1998 Microchip Technology Inc. DS40139D-page 19

PIC12C5XX

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

Direct Addressing

(FSR)

bank select

location select

(opcode) 04

00 01

00h

Data Memory

0Fh

(1)

10h

1Fh 3Fh

Bank 0 Bank 1

Note 1: For register map detail see Section 4.2. Note 2: PIC12C509(A) only

Addresses map back to addresses in Bank 0.

(2)

Indirect Addressing

bank

(FSR)

location select

DS40139D-page 20  1998 Microchip Technology Inc.

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 port 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 up 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-

, weak pull-

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

Data Bus

WR Port

W Reg

TRIS ‘f’

Data Latch

TRIS Latch

Reset

VDD

(2)

VSS

I/O pin

(1)

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

Note 1: I/O pins have protection diodes to VDD and VSS.

2: See Table 3-1 for buffer type.

RD Port

low.

The TRIS registers are “write-only” and are set (output drivers disabled) upon RESET.

TABLE 5-1: SUMMARY OF PORT REGISTERS

Value on

Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

N/A TRIS I/O control registers --11 1111 --11 1111 N/A

03H 06h

Legend: Shaded cells not used by Port Registers, read as ‘0’, — = unimplemented, read as '0', x = unknown, u = unchanged,

Note 1: If reset was due to wake-up on change, then bit 7 = 1. All other resets will cause bit 7 = 0.

OPTION GPWU GPPU T0CS T0SE PSA PS2 PS1 PS0

STATUS GPIO

q = see tables in Section 7.7 for possible values.

GPWUF — PAO TO PD Z DC C 0001 1xxx q00q quuu

— — GP5 GP4 GP3 GP2 GP1 GP0 --xx xxxx --uu uuuu

Power-On

Reset

1111 1111 1111 1111

Value on

All Other Resets

(1)

 1998 Microchip Technology Inc. DS40139D-page 21

PIC12C5XX

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

NOP

Instruction

fetched

GP5:GP0

Instruction

executed

Q1 Q2

MOVWF GPIO

PC PC + 1 PC + 2

Q1 Q2

MOVF GPIO,W

Port pin written here

MOVWF GPIO

(Write to

GPIO)

Q1 Q2

Port pin sampled here

MOVF GPIO,W

(Read

GPIO)

Q1 Q2

PC + 3

NOP

This example shows a write to GPIO follow ed 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.

DS40139D-page 22  1998 Microchip Technology Inc.

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.

FIGURE 6-1: TIMER0 BLOCK DIAGRAM

GP2/T0CKI

T0SE

FOSC/4

T0CS

PS2, PS1, PS0

(1)

Programmable

Prescaler

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.

Data bus

PSout

(2)

PSA

(1)

Sync with

Internal

Clocks

CY delay)

(2 T

TMR0 reg

PSout

Sync

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).

 1998 Microchip Technology Inc. DS40139D-page 23

PIC12C5XX

FIGURE 6-2: TIMER0 TIMING: INTERNAL CLOCK/NO PRESCALE

PC (Program Counter)

Instruction

Fetch

Timer0

Instruction Executed

Q1 Q2 Q3 Q4

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

PC PC+1 PC+2 PC+3 PC+4 PC+5 PC+6

MOVWF TMR0

T0+1 T0+2 NT0 NT0+1 NT0+2

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 + 1

Read TMR0 reads NT0 + 2

FIGURE 6-3: TIMER0 TIMING: INTERNAL CLOCK/PRESCALE 1:2

PC (Program Counter)

Instruction

Fetch

Timer0

Instruction Execute

Q1 Q2 Q3 Q4

PC-1

T0 NT0+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

PC PC+1 PC+2 PC+3 PC+4 PC+5 PC+6

MOVWF TMR0

T0+1

MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W

NT0

Write TMR0 executed

Read TMR0 reads NT0

Read TMR0 reads NT0 + 1

TABLE 6-1: REGISTERS ASSOCIATED WITH TIMER0

Value on

Power-On

Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

Reset

01h TMR0 Timer0 - 8-bit real-time clock/counter xxxx xxxx uuuu uuuu N/A OPTION

N/A TRIS Legend: Shaded cells not used by Timer0,

GPWU GPPU T0CS T0SE PSA PS2 PS1 PS0 1111 1111 1111 1111

—

— GP5 GP4 GP3 GP2 GP1 GP0

- = unimplemented, x = unknown, u = unchanged,

--11 1111 --11 1111

Value on All Other

Resets

DS40139D-page 24  1998 Microchip Technology Inc.

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 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 and low for at least 2T

OSC (and a small RC delay of 20 ns)

OSC (and a small RC delay of

20 ns). Refer to the electrical speciﬁcation of the desired device.

OSC)

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

Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4

External Clock Input or

Prescaler Output (2)

External Clock/Prescaler Output After Sampling

Increment Timer0 (Q4)

Note 1:

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.

(3)

Timer0

(1)

T0 T0 + 1 T0 + 2

Small pulse misses sampling

 1998 Microchip Technology Inc. DS40139D-page 25

PIC12C5XX

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

(TIMER0→WDT)

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 bef ore switching the prescaler.

EXAMPLE 6-2: CHANGING PRESCALER

(WDT→TIMER0)

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)

M U

PSA

T0CS

M U

8-bit Prescaler

8 - to - 1MUX

MUX

M U

PSA

Sync

Cycles

PS2:PS0

GP2/T0CKI

T0SE

Watchdog

Timer

WDT Enable bit

Data Bus

TMR0 reg

WDT

Time-Out

Note: T0CS, T0SE, PSA, PS2:PS0 are bits in the OPTION register.

DS40139D-page 26  1998 Microchip Technology Inc.

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

bit11 10 9 8 7 6 5 4 3 2 1 bit0

bit 11-5: Unimplemented bit 4: MCLRE: MCLR

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.

enable bit.

Address

(1)

: FFFh

 1998 Microchip Technology Inc. DS40139D-page 27

PIC12C5XX

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)

(1)

OSC1

PIC12C5XX

TABLE 7-1: CAPACITOR SELECTION

FOR CERAMIC RESONATORS

- PIC12C5XX

Osc

Type

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.

Resonator

Freq

XT 4.0 MHz 30 pF 30 pF

Cap. RangeC1Cap. Range

T ABLE 7-2: CAPACITOR SELECTION

FOR CRYSTAL OSCILLATOR

- PIC12C5XX

Osc

Type

Note 1: For V 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.

Resonator

Freq

LP 32 kHz XT 200 kHz

1 MHz 4 MHz

DD > 4.5V, C1 = C2 ≈ 30 pF is

recommended.

(1)

Cap.Range

15 pF 15 pF

47-68 pF

15 pF 15 pF

Cap. Range

47-68 pF

15 pF 15 pF

XTAL

OSC2

(2)

(1)

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.

(3)

SLEEP

To internal

logic

FIGURE 7-3: EXTERNAL CLOCK INPUT

OPERATION (XT OR LP OSC CONFIGURATION)

Clock from ext. system

Open

OSC1

PIC12C5XX

OSC2

DS40139D-page 28  1998 Microchip Technology Inc.

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 kΩ resistor provides the negative feedback for stability. The 10 kΩ 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

+5V

10k

4.7k

74AS04

10k

XTAL

10k

20 pF

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.

74AS04

To Other Devices

PIC12C5XX

CLKIN

FIGURE 7-5: EXTERNAL SERIES

RESONANT CRYSTAL OSCILLATOR CIRCUIT

To Other

74AS04

Devices

PIC12C5XX

CLKIN

330

74AS04

330

74AS04

0.1 µF XTAL

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 MΩ) the oscillator becomes sensitive to noise, humidity and leakage. Thus, we recommend keeping Rext between 3 kΩ 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

OSC1

Internal clock

PIC12C5XX

 1998 Microchip Technology Inc. DS40139D-page 29

PIC12C5XX

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 programmed 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. .

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.

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.

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.

7.3 RESET

The device differentiates between various kinds of reset:

a) Power on reset (POR) b) MCLR c) MCLR 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 change reset during normal operation. They are not affected by a WDT reset during SLEEP or MCLR during SLEEP, since these resets are viewed as resumption of normal operation. The exceptions to this

DS40139D-page 30  1998 Microchip Technology Inc.

reset during normal operation reset during SLEEP

, WDT or wake-up on pin

reset

PIC12C5XX

TABLE 7-3: RESET CONDITIONS FOR REGISTERS

Reset

MCLR

W (PIC12C508/509) —

W (PIC12C508A/509A) —

INDF 00h xxxx xxxx uuuu uuuu

TMR0 01h xxxx xxxx uuuu uuuu

PC 02h 1111 1111 1111 1111

STATUS 03h 0001 1xxx

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.

qqqq xxxx qqqq qqxx

(1)

WDT time-out

Wake-up on Pin Change

qqqq uuuu qqqq qquu

q00q quuu

(1)

(2,3)

TABLE 7-4: RESET CONDITION FOR SPECIAL REGISTERS

STATUS Addr: 03h PCL Addr: 02h

Power on reset 0001 1xxx 1111 1111

reset during normal operation 000u uuuu 1111 1111

MCLR

reset during SLEEP 0001 0uuu 1111 1111

MCLR 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’.

 1998 Microchip Technology Inc. DS40139D-page 31

PIC12C5XX

7.3.1 MCLR ENABLE This conﬁguration bit when unprogrammed (left in the

‘1’ state) enables the external MCLR programmed, the MCLR V

DD, and the pin is assigned to be a GPIO. See

function is tied to the internal

Figure 7-7. When pin GP3/MCLR MCLR

, the internal pull-up is always on.

function. When

/VPP is conﬁgured as

FIGURE 7-7: MCLR SELECT

MCLRE

WEAK PULL-UP

GP3/MCLR/VPP

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 tor to V

DD or program the pin as GP3. An internal weak

/VPP pin as MCLR and tie thru a resis-

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 is speciﬁed. See Electrical Speciﬁcations for details.

When the device starts normal operation (exits the reset condition), device operating parameters (v oltage , 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.

INTERNAL MCLR

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 shown in Figure 7-9. V

DD is allowed to rise and

stabilize before bringing MCLR actually come out of reset T

is held low is

high. The chip will

DRT msec after MCLR

goes high. In Figure 7-10, the on-chip Power-On Reset feature is

being used (MCLR pin is programmed to be GP3.). The V

and VDD are tied together or the

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 V

DD (min) value and the chip is, therefore, not

DD has not reached the

guaranteed to function correctly. For such situations, we recommend that external RC circuits be used to achieve longer POR delay times (Figure 7-10).

Note: When the device starts nor mal 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.

For additional information refer to Application Notes “

Power-Up Considerations”

Trouble Shooting

” - AN607.

- AN522 and “

Power-up

DS40139D-page 32  1998 Microchip Technology Inc.

PIC12C5XX

FIGURE 7-8: SIMPLIFIED BLOCK DIAGRAM OF ON-CHIP RESET CIRCUIT

Power-Up

VDD

GP3/MCLR/VPP

Detect

POR (Power-On Reset)

Pin Change

SLEEP

Wake-up on pin change

MCLRE

On-Chip

DRT OSC

WDT Time-out

8-bit Asynch

Ripple Counter

(Start-Up Timer)

FIGURE 7-9: TIME-OUT SEQUENCE ON POWER-UP (MCLR

VDD

MCLR

INTERNAL POR

DRT TIME-OUT

INTERNAL RESET

FIGURE 7-10: TIME-OUT SEQUENCE ON POWER-UP (MCLR

RESET

S Q

CHIP RESET

PULLED LOW)

TDRT

TIED TO VDD): FAST VDD RISE TIME

VDD

MCLR

INTERNAL POR

DRT TIME-OUT

INTERNAL RESET

 1998 Microchip Technology Inc. DS40139D-page 33

TDRT

PIC12C5XX

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

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.

TDRT

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 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 level. Thus, programming GP3/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 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.

has reached a logic high (VIHMCLR)

DD, temperature, and process variation. See

DD to rise above VDD

/VPP as MCLR

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

IntRC & ExtRC

XT & LP 18 ms (typical) 18 ms (typical)

POR Reset

18 ms (typical) 300 µs (typical)

Subsequent

Resets

DS40139D-page 34  1998 Microchip Technology Inc.

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.

FIGURE 7-12: WATCHDOG TIMER BLOCK DIAGRAM

From Timer0 Clock Source (Figure 6-5)

Watchdog

Timer

WDT Enable

Conﬁguration Bit

U X

PSA

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.

Postscaler

8 - to - 1 MUX

PS2:PS0

To Timer0 (Figure 6-4)

MUX

WDT

PSA

Time-out

TABLE 7-6: SUMMARY OF REGISTERS ASSOCIATED WITH THE WATCHDOG TIMER

Value on

Power-On

Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

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

Reset

Value on All Other

Resets

 1998 Microchip Technology Inc. DS40139D-page 35

PIC12C5XX

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 Watchdog Timer (WDT) reset.

TABLE 7-7: TO/PD/GPWUF STATUS

AFTER RESET

GPWUF TO PD RESET caused by

0 0 0

0 0 u

0 1 0

0 1 1 0 u u 1 1 0

Legend: Legend: u = unchanged

Note 1: The TO, PD, and GPWUF bits main-

WDT wake-up from SLEEP

WDT time-out (not from SLEEP)

MCLR wake-up from SLEEP

Power-up MCLR not during SLEEP Wake-up from SLEEP on

pin change

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.u

DS40139D-page 36  1998 Microchip Technology Inc.

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 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

For lowest current consumption while powered down, the T0CKI input should be at V 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 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 GPWUF bits can be used to determine the cause of device reset. The T occurred (and caused wake-up). The PD 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).

O bit (STATUS<4>) is set, the PD

pin low.

DD or VSS and the GP3/

/VPP pin,

O, PD, and

O bit is cleared if a WDT time-out

bit, which is

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.

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.

The WDT is cleared when the device wakes from sleep, regardless of the wake-up source.

 1998 Microchip Technology Inc. DS40139D-page 37

PIC12C5XX

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

To Normal

External Connector Signals

+5V

VPP

CLK

Data I/O

Connections

To Normal Connections

PIC12C5XX

V VSS MCLR/VPP

GP1

GP0

VDD

DS40139D-page 38  1998 Microchip Technology Inc.

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

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.

Destination select;

label Label name

TOS Top of Stack

PC Program Counter

WDT Watchdog Timer Counter

TO PD Power-Down bit

dest

[ ]

( )

→

< >

∈

talics

d = 0 (store result in W) d = 1 (store result in ﬁle register 'f')

Default is d = 1

Time-Out bit

Destination, either the W register or the speciﬁed register ﬁle location

Options Contents Assigned to Register bit ﬁeld In the set of 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 instruction 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

OPCODE d f (FILE #)

d = 0 for destination W 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

 1998 Microchip Technology Inc. DS40139D-page 39

PIC12C5XX

TABLE 8-2: INSTRUCTION SET SUMMARY

Mnemonic,

Operands Description Cycles

ADDWF ANDWF CLRF CLRW COMF DECF DECFSZ INCF INCFSZ IORWF MOVF MOVWF NOP RLF RRF SUBWF SWAPF XORWF

BIT-ORIENTED FILE REGISTER OPERATIONS BCF

BSF BTFSC BTFSS

LITERAL AND CONTROL OPERATIONS ANDLW

CALL CLRWDT GOTO IORLW MOVLW OPTION RETLW SLEEP TRIS XORLW

Note 1: The 9th bit of the program counter will be forced to a '0' by any instruction that writes to the PC except for GOTO .

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

3: The instruction TRIS f, where f = 6 causes the contents of the W register to be written to the tristate latches of 4: If this instruction is executed on the TMR0 register (and, where applicab le , d = 1), the prescaler will be cleared

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

f, b f, b f, b f, b

k k k k k k – k – f k

(Section 4.6) 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 bac k with a '0'. GPIO. A '1' forces the pin to a hi-impedance state and disables the output buffers. (if assigned to TMR0).

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

Bit Clear f Bit Set f Bit Test f, Skip if Clear Bit Test f, Skip if Set

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 1 1 1 1 1

1(2)

1 1 1 1 1 1 1 1 1

1 1 (2) 1 (2)

12-Bit Opcode

0001 0001 0000 0000 0010 0000 0010 0010 0011 0001 0010 0000 0000 0011 0011 0000 0011 0001

0100 0101 0110 0111

1110 1001 0000 101k 1101 1100 0000 1000 0000 0000 1111

11df 01df 011f 0100 01df 11df 11df 10df 11df 00df 00df 001f 0000 01df 00df 10df 10df 10df

bbbf bbbf bbbf bbbf

kkkk kkkk 0000 kkkk kkkk kkkk 0000 kkkk 0000 0000 kkkk

ffff ffff ffff 0000 ffff ffff ffff ffff ffff ffff ffff ffff 0000 ffff ffff ffff ffff ffff

ffff ffff ffff ffff

kkkk kkkk 0100 kkkk kkkk kkkk 0010 kkkk 0011 0fff kkkk

Status

Affected NotesMSb LSb

C,DC,Z

Z Z Z Z Z

None

Z None None

C,DC,Z

None

None None None None

Z None

O, PD

None

Z None None None

O, PD

None

1,2,4

2,4

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

DS40139D-page 40  1998 Microchip Technology Inc.

PIC12C5XX

ADDWF Add W and f

label

Syntax: [

] ADDWF f,d

Operands: 0 ≤ f ≤ 31

d ∈ [0,1] Operation: (W) + (f) → (dest) Status Affected: C, DC, Z Encoding: Description:

0001 11df ffff

Add the contents of the W register and

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

label

Syntax: [

] ANDLW k Operands: 0 ≤ k ≤ 255 Operation: (W).AND. (k) → (W) Status Affected: Z Encoding: Description:

1110 kkkk kkkk

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

label

Syntax: [

] ANDWF f,d

Operands: 0 ≤ f ≤ 31

d ∈ [0,1] Operation: (W) .AND. (f) → (dest) Status Affected: Z Encoding: Description:

0001 01df ffff

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

label

Syntax: [

] BCF f,b

Operands: 0 ≤ f ≤ 31

0 ≤ b ≤ 7 Operation: 0 → (f<b>) Status Affected: None Encoding: Description:

Words: 1

0100 bbbf ffff

Bit 'b' in register 'f' is cleared.

Cycles: 1 Example:

BCF FLAG_REG, 7

Before Instruction

FLAG_REG = 0xC7

After Instruction

FLAG_REG = 0x47

 1998 Microchip Technology Inc. DS40139D-page 41

PIC12C5XX

BSF Bit Set f

label

Syntax: [

] BSF f,b

Operands: 0 ≤ f ≤ 31

0 ≤ b ≤ 7 Operation: 1 → (f<b>) Status Affected: None Encoding: Description:

0101 bbbf ffff

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

label

Syntax: [

] BTFSC f,b

Operands: 0 ≤ f ≤ 31

0 ≤ b ≤ 7 Operation: skip if (f<b>) = 0 Status Affected: None Encoding: 0110 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.

bbbf ffff

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

label

Syntax: [

] BTFSS f,b

Operands: 0 ≤ f ≤ 31

0 ≤ b < 7 Operation: skip if (f<b>) = 1 Status Affected: None Encoding: Description:

0111 bbbf ffff

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)

DS40139D-page 42  1998 Microchip Technology Inc.

PIC12C5XX

CALL Subroutine Call

label

Syntax: [

] 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: Description:

1001 kkkk kkkk

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

label

Syntax: [

] CLRF f Operands: 0 ≤ f ≤ 31 Operation: 00h → (f);

1 → Z Status Affected: Z Encoding: Description:

0000 011f ffff

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

label

Syntax: [

] CLRW Operands: None Operation: 00h → (W);

1 → Z Status Affected: Z Encoding: Description:

0000 0100 0000

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

label

Syntax: [

] CLRWDT Operands: None Operation: 00h → WDT;

0 → WDT prescaler (if assigned);

1 → T

1 → PD Status Affected: TO, PD Encoding: Description:

0000 0000 0100

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

 1998 Microchip Technology Inc. DS40139D-page 43

PIC12C5XX

COMF Complement f

label

Syntax: [

] COMF f,d

Operands: 0 ≤ f ≤ 31

d ∈ [0,1]

Operation: (f

) → (dest) Status Affected: Z Encoding: Description:

0010 01df ffff

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

label

Syntax: [

] DECF f,d

Operands: 0 ≤ f ≤ 31

d ∈ [0,1] Operation: (f) – 1 → (dest) Status Affected: Z Encoding: Description:

0000 11df ffff

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,

Before Instruction

CNT = 0x01 Z = 0

After Instruction

CNT = 0x00 Z = 1

DECFSZ Decrement f, Skip if 0

label

Syntax: [

] DECFSZ f,d

Operands: 0 ≤ f ≤ 31

d ∈ [0,1] Operation: (f) – 1 → d; skip if result = 0 Status Affected: None Encoding: Description:

0010 11df ffff

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

label

Syntax: [

] GOTO k Operands: 0 ≤ k ≤ 511 Operation: k → PC<8:0>;

STATUS<6:5> → PC<10:9> Status Affected: None Encoding: Description:

101k kkkk kkkk

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)

DS40139D-page 44  1998 Microchip Technology Inc.

PIC12C5XX

INCF Increment f

label

Syntax: [

] INCF f,d

Operands: 0 ≤ f ≤ 31

d ∈ [0,1] Operation: (f) + 1 → (dest) Status Affected: Z Encoding: Description:

0010 10df ffff

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,

Before Instruction

CNT = 0xFF Z = 0

After Instruction

CNT = 0x00 Z = 1

INCFSZ Increment f, Skip if 0

label

Syntax: [

] INCFSZ f,d

Operands: 0 ≤ f ≤ 31

d ∈ [0,1] Operation: (f) + 1 → (dest), skip if result = 0 Status Affected: None Encoding: Description:

0011 11df ffff

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

label

Syntax: [

] IORLW k Operands: 0 ≤ k ≤ 255 Operation: (W) .OR. (k) → (W) Status Affected: Z Encoding: Description:

1101 kkkk kkkk

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

label

Syntax: [

] IORWF f,d Operands: 0 ≤ f ≤ 31

d ∈ [0,1] Operation: (W).OR. (f) → (dest) Status Affected: Z Encoding: Description:

0001 00df ffff

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

 1998 Microchip Technology Inc. DS40139D-page 45

PIC12C5XX

MOVF Move f

label

Syntax: [

] MOVF f,d

Operands: 0 ≤ f ≤ 31

d ∈ [0,1] Operation: (f) → (dest) Status Affected: Z Encoding: Description:

0010 00df ffff

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

label

Syntax: [

] MOVLW k Operands: 0 ≤ k ≤ 255 Operation: k → (W) Status Affected: None Encoding: Description:

1100 kkkk kkkk

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

label

Syntax: [

] MOVWF f Operands: 0 ≤ f ≤ 31 Operation: (W) → (f) Status Affected: None Encoding: Description:

0000 001f ffff

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

label

Syntax: [

] NOP Operands: None Operation: No operation Status Affected: None Encoding:

0000 0000 0000

Description: No operation. Words: 1 Cycles: 1 Example:

NOP

DS40139D-page 46  1998 Microchip Technology Inc.

PIC12C5XX

OPTION Load OPTION Register

label

Syntax: [

] OPTION Operands: None Operation: (W) → OPTION Status Affected: None Encoding: Description:

0000 0000 0010

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

label

Syntax: [

] RETLW k Operands: 0 ≤ k ≤ 255 Operation: k → (W);

TOS → PC Status Affected: None Encoding: Description:

1000 kkkk kkkk

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

label

Syntax: [

] RLF f,d

Operands: 0 ≤ f ≤ 31

d ∈ [0,1] Operation: See description below Status Affected: C Encoding: Description:

0011 01df ffff

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

label

Syntax: [

] RRF f,d

Operands: 0 ≤ f ≤ 31

d ∈ [0,1] Operation: See description below Status Affected: C Encoding: Description:

0011 00df ffff

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

 1998 Microchip Technology Inc. DS40139D-page 47

PIC12C5XX

SLEEP Enter SLEEP Mode

Syntax:

label

[

]

SLEEP Operands: None Operation: 00h → WDT;

0 → WDT prescaler;

1 → T

0 → PD Status Affected: TO, PD, GPWUF Encoding: Description:

0000 0000 0011

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: Description:

0000 10df ffff

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

SUBWF REG1, 1

Example 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

DS40139D-page 48  1998 Microchip Technology Inc.

PIC12C5XX

SWAPF Swap Nibbles in f

label

Syntax: [

] 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: Description:

0011 10df ffff

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

label

Syntax: [ Operands: f =

] TRIS f

Operation: (W) → TRIS register f Status Affected: None Encoding: Description:

0000 0000 0fff

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: Description:

1111 kkkk kkkk

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

label

Syntax: [

] XORWF f,d

Operands: 0 ≤ f ≤ 31

d ∈ [0,1] Operation: (W) .XOR. (f) → (dest) Status Affected: Z Encoding: Description:

0001 10df ffff

Exclusive OR the contents of the W

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

 1998 Microchip Technology Inc. DS40139D-page 49

PIC12C5XX

NOTES:

DS40139D-page 50  1998 Microchip Technology Inc.

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

• PICSTART Programmer

• SIMICE

• PICDEM-1 Low-Cost Demonstration Board

• PICDEM-2 Low-Cost Demonstration Board

• PICDEM-3 Low-Cost Demonstration Board

• MPASM Assembler

• MPLAB SIM Software Simulator

• MPLAB-C17 (C Compiler)

• Fuzzy Logic Development System (

fuzzy

• K

EELOQ

9.2 MPLAB-ICE: High Performance



II Universal Programmer



Plus Entry-Level Prototype

TECH−MP)

Evaluation Kits and Programmer

Universal In-Circuit Emulator with MPLAB IDE

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 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.

DD and VPP

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 Dev elopment Environment (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 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.



3.x or

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.

 1998 Microchip Technology Inc. DS40139D-page 51

PIC12C5XX

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 tion to an LCD module and a keypad.

C bus and separate headers for connec-

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.

DS40139D-page 52  1998 Microchip Technology Inc.

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 y our assemble 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 de velop 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, menting more complex systems.

Both versions include Microchip’s stration board for hands-on experience with fuzzy logic systems implementation.

fuzzy

TECH-MP, Edition for imple-

fuzzy

LAB demon-

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.

 1998 Microchip Technology Inc. DS40139D-page 53

PIC12C5XX

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.

DS40139D-page 54  1998 Microchip Technology Inc.

 1998 Microchip Technology Inc. DS40139D-page 55

PIC12C5XX PIC14000 PIC16C5X PIC16CXXX PIC16C6X PIC16C7XX PIC16C8X PIC16C9XX PIC17C4X PIC17C7XX

24CXX 25CXX 93CXX

TABLE 9-1: DEVELOPMENT TOOLS FROM MICROCHIP

HCS200 HCS300 HCS301

MPLAB™-ICE

ICEPIC Low-Cost In-Circuit Emulator

Emulator Products

MPLAB Integrated Development Environment

MPLAB C17* Compiler

fuzzy

TECH-MP Explorer/Edition Fuzzy Logic

Software Tools

Dev. Tool Total Endurance

Software Model PICSTARTPlus

Low-Cost Universal Dev. Kit

PRO MATE Universal Programmer

Programmers

KEELOQ Programmer

SEEVAL Designers Kit

SIMICE PICDEM-14A PICDEM-1 PICDEM-2 PICDEM-3

Demo Boards

EELOQ

K Evaluation Kit

EELOQ

K Transponder Kit



ü ü ü ü ü ü ü ü ü ü

ü ü ü ü ü ü

ü ü ü ü ü ü ü ü ü ü

ü ü

ü ü ü ü ü ü ü ü ü

ü ü ü ü ü ü ü ü ü ü

ü ü ü ü ü ü ü ü ü ü ü ü

ü ü

ü ü ü ü

ü ü

PIC12C5XX

NOTES:

DS40139D-page 56  1998 Microchip Technology Inc.

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 Voltage on MCLR Voltage on all other pins with respect to V Total Power Dissipation Max. Current out of V Max. Current into V Input Clamp Current, I Output Clamp Current, I

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

†

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.

DD with respect to VSS .................................................................................................................0 to +7.5 V

with respect to VSS...............................................................................................................0 to +14 V

SS ................................................................................–0.6 V to (VDD + 0.6 V)

(1)

....................................................................................................................................700 mW

SS pin...................................................................................................................................200 mA

DD pin......................................................................................................................................150 mA

IK (VI < 0 or VI > VDD) ....................................................................................................................±20 mA

OK (VO < 0 or VO > VDD) ............................................................................................................±20 mA

DIS = VDD x {IDD - ∑ IOH} + ∑ {(VDD-VOH) x IOH} + ∑(VOL x IOL)

 1998 Microchip Technology Inc. DS40139D-page 57

PIC12C5XX

10.1 DC CHARACTERISTICS: PIC12C508/509 (Commercial, Industrial, Extended)

Standard Operating Conditions (unless otherwise speciﬁed)

DC Characteristics

Power Supply Pins

Operating Temperature 0°C ≤ TA ≤ +70°C (commercial)

–40°C ≤ T –40°C ≤ T

A ≤ +85°C (industrial) A ≤ +125°C (extended)

Characteristic Sym Min

Supply Voltage V

RAM Data Retention Voltage

(2)

DD Start Voltage to ensure

VPOR VSS V See section on Power-on Reset for details

Power -on Reset

DD Rise Rate to ensure

SVDD 0.05* V/ms See section on Power-on Reset for details

Power-on Reset Supply Current

(3)

∆IWDT

Power-Down Current

(5)

(1)

Typ

DD 2.5

Max Units Conditions

5.5

VVFOSC = DC to 4 MHz (Commercial/

Industrial)

3.0

5.5

OSC = DC to 4 MHz (Extended)

VDR 1.5* V Device in SLEEP mode

XT and EXTRC options (Note 4)

IDD

— — — — —

— — —

IPD —

— —

1.8

1.8 15 19 19

3.75

0.25

0.25 2

2.4

2.4 27 35 35

OSC = 4 MHz, VDD = 5.5V

INTRC Option F

OSC = 4 MHz, VDD = 5.5V

µA

LP O

PTION, Commercial Temperature

OSC = 32 kHz, VDD = 3.0V, WDT disabled

µA

LP O

PTION, Industrial Temperature

OSC = 32 kHz, VDD = 3.0V, WDT disabled

µA

LP O

PTION, Extended Temperature

OSC = 32 kHz, VDD = 3.0V, WDT disabled-

µA

8 9 4

4 5

DD = 3.0V, Commercial

µA

DD = 3.0V, Industrial

µA

DD = 3.0V, Extended

µA

VDD = 3.0V, Commercial

µA

DD = 3.0V, Industrial

µA

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.

DS40139D-page 58  1998 Microchip Technology Inc.

PIC12C5XX

10.2 DC CHARACTERISTICS: PIC12C508/509 (Commercial, Industrial, Extended)

Standard Operating Conditions (unless otherwise speciﬁed)

Operating temperature 0˚C ≤ T

DC CHARACTERISTICS

Operating voltage V

–40˚C ≤ T –40°C ≤ T

DD range as described in DC spec Section 10.1 and

Section 10.2.

Param

Characteristic Sym Min Typ†Max Units Conditions

No.

Input Low Voltage

I/O ports V

D030 with TTL buffer VSS - 0.5V V D031 with Schmitt Trigger buffer V D032 MCLR

, GP2/T0CKI/AN2/INT

SS - 0.2VDD V

VSS - 0.2VDD V

(in EXTRC mode)

D033 OSC1 (in XT, HS and LP) V

SS - 0.3VDD V Note1

Input High Voltage

I/O ports V D040 with TTL buffer 2.0 - V D040A 0.8V D041 with Schmitt Trigger buffer 0.8V D042 MCLR

, GP2/T0CKI/AN2/INT 0.8VDD - VDD V D042A OSC1 (XT, HS and LP) 0.7V D043 OSC1 (in EXTRC mode) 0.9V D070 GPIO weak pull-up current I

IH -

DD V 4.5 ≤ VDD ≤ 5.5V DD - VDD V For VDD > 5.5V or VDD < 4.5V DD - VDD V For entire VDD range

DD - VDD V Note1 DD - VDD V

PUR 50 250 400 µA VDD = 5V, VPIN = VSS

Input Leakage Current (Notes 2, 3)

D060 I/O ports I

D061 MCLR

, GP2/T0CKI - -

IL - - +1 µA Vss ≤ VPIN ≤ VDD, Pin at hi-

(5)

D063 OSC1 - - +5 µA Vss ≤ VPIN ≤ VDD, XT , HS and LP

Output Low Voltage

D080 I/O ports/CLKOUT V

OL - - 0.6 V IOL = 8.5 mA, VDD = 4.5V,

D080A - - 0.6 V I

D083 OSC2 - - 0.6 V I

D083A - - 0.6 V I

† 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 level. 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.

A ≤ +70˚C (commercial) A ≤ +85˚C (industrial) A ≤ +125˚C (extended)

impedance

µA Vss ≤ VPIN ≤ VDD

osc conﬁguration

–40°C to +85°C

OL = 7.0 mA, VDD = 4.5V,

–40°C to +125°C

OL = 1.6 mA, VDD = 4.5V,

–40°C to +85°C

OL = 1.2 mA, VDD = 4.5V,

–40°C to +125°C

 1998 Microchip Technology Inc. DS40139D-page 59

PIC12C5XX

Standard Operating Conditions (unless otherwise speciﬁed)

Operating temperature 0˚C ≤ T

DC CHARACTERISTICS

Operating voltage V

–40˚C ≤ T –40°C ≤ T

DD range as described in DC spec Section 10.1 and

Section 10.2.

Param

Characteristic Sym Min Typ†Max Units Conditions

No.

Output High Voltage

D090 I/O ports/CLKOUT (Note 3) V

D090A V

D092 OSC2 V

D092A V

OH VDD - 0.7 - - V IOH = -3.0 mA, VDD = 4.5V,

DD - 0.7 - - V IOH = -2.5 mA, VDD = 4.5V,

DD - 0.7 - - V IOH = -1.3 mA, VDD = 4.5V,

DD - 0.7 - - V IOH = -1.0 mA, VDD = 4.5V,

Capacitive Loading Specs on Output Pins

D100 OSC2 pin C

D101 All I/O pins and OSC2 C

OSC2 - - 15 pF In XT, HS and LP modes when

IO - - 50 pF

† 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 level. 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.

A ≤ +70˚C (commercial) A ≤ +85˚C (industrial) A ≤ +125˚C (extended)

–40°C to +85°C

–40°C to +125°C

–40°C to +85°C

–40°C to +125°C

external clock is used to drive OSC1.

DS40139D-page 60  1998 Microchip Technology Inc.

PIC12C5XX

PICLC508/509 (Commer( )T172 72BT10 0cial,( )T1.904BT10 0gy dustrial)( )T910 0 9 119.948 693.5 haracteristics( )Tj007 -12.210 0( )Tj627BT10 0o( )Tj594BT10 0wer Suppl9D

 1998 Microchip Technology Inc. DS40139D-page 61

PIC12C5XX

10.4 DC CHARACTERISTICS: PIC12LC508/509 (Commercial, Industrial)

Standard Operating Conditions (unless otherwise speciﬁed)

Operating temperature 0˚C ≤ T

DC CHARACTERISTICS

Operating voltage V

–40˚C ≤ T

DD range as described in DC spec Section 10.1 and

Section 10.2.

Param

Characteristic Sym Min Typ†Max Units Conditions

No.

Input Low Voltage

I/O ports V

D030 with TTL buffer VSS - 0.5V V D031 with Schmitt Trigger buffer V D032 MCLR

, GP2/T0CKI/AN2/INT

SS - 0.2VDD V

VSS - 0.2VDD V

(in EXTRC mode)

D033 OSC1 (in XT, HS and LP) V

SS - 0.3VDD V Note1

Input High Voltage

I/O ports V D040 with TTL buffer 2.0 - V D040A 0.8V D041 with Schmitt Trigger buffer 0.8V D042 MCLR

, GP2/T0CKI/AN2/INT 0.8VDD - VDD V D042A OSC1 (XT, HS and LP) 0.7V D043 OSC1 (in EXTRC mode) 0.9V D070 GPIO weak pull-up current I

IH -

DD V 4.5 ≤ VDD ≤ 5.5V DD - VDD V For VDD > 5.5V or VDD < 4.5V DD - VDD V For entire VDD range

DD - VDD V Note1 DD - VDD V

PUR 50 250 400 µA VDD = 5V, VPIN = VSS

Input Leakage Current (Notes 2, 3)

D060 I/O ports I

D061 MCLR

, GP2/T0CKI - -

IL - - +1 µA Vss ≤ VPIN ≤ VDD, Pin at hi-

(5)

D063 OSC1 - - +5 µA Vss ≤ VPIN ≤ VDD, XT , HS and LP

Output Low Voltage

D080 I/O ports/CLKOUT V

OL - - 0.6 V IOL = 8.5 mA, VDD = 4.5V,

D080A - - 0.6 V I

D083 OSC2 - - 0.6 V I

D083A - - 0.6 V I

† 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 level. 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.

A ≤ +70˚C (commercial)

A ≤ +85˚C (industrial)

impedance

µA Vss ≤ VPIN ≤ VDD

osc conﬁguration

–40°C to +85°C

OL = 7.0 mA, VDD = 4.5V,

–40°C to +125°C

OL = 1.6 mA, VDD = 4.5V,

–40°C to +85°C

OL = 1.2 mA, VDD = 4.5V,

–40°C to +125°C

DS40139D-page 62  1998 Microchip Technology Inc.

PIC12C5XX

Standard Operating Conditions (unless otherwise speciﬁed)

Operating temperature 0˚C ≤ T

DC CHARACTERISTICS

Operating voltage V

–40˚C ≤ T

DD range as described in DC spec Section 10.1 and

Section 10.2.

Param

Characteristic Sym Min Typ†Max Units Conditions

No.

Output High Voltage

D090 I/O ports/CLKOUT (Note 3) V

D090A V

D092 OSC2 V

D092A V

OH VDD - 0.7 - - V IOH = -3.0 mA, VDD = 4.5V,

DD - 0.7 - - V IOH = -2.5 mA, VDD = 4.5V,

DD - 0.7 - - V IOH = -1.3 mA, VDD = 4.5V,

DD - 0.7 - - V IOH = -1.0 mA, VDD = 4.5V,

Capacitive Loading Specs on Output Pins

D100 OSC2 pin C

D101 All I/O pins and OSC2 C

OSC2 - - 15 pF In XT, HS and LP modes when

IO - - 50 pF

† 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 level. 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.

A ≤ +70˚C (commercial)

A ≤ +85˚C (industrial)

–40°C to +85°C

–40°C to +125°C

–40°C to +85°C

–40°C to +125°C

external clock is used to drive OSC1.

 1998 Microchip Technology Inc. DS40139D-page 63

PIC12C5XX

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 Ω 25 42K 48K 63K Ω 85 42K 49K 63K Ω

125 50K 55K 63K Ω

5.5 –40 15K 17K 20K Ω 25 18K 20K 23K Ω 85 19K 22K 25K Ω

125 22K 24K 28K Ω

GP3

2.5 –40 285K 346K 417K Ω 25 343K 414K 532K Ω 85 368K 457K 532K Ω

125 431K 504K 593K Ω

5.5 –40 247K 292K 360K Ω 25 288K 341K 437K Ω 85 306K 371K 448K Ω

125 351K 407K 500K Ω

* These parameters are characterized but not tested.

DS40139D-page 64  1998 Microchip Technology Inc.

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

F Frequency T Time Lowercase subscripts (pp) and their meanings:

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:

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

VSS

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

 1998 Microchip Technology Inc. DS40139D-page 65

PIC12C5XX

10.6 Timing Diagrams and Speciﬁcations FIGURE 10-2: EXTERNAL CLOCK TIMING - PIC12C508/C509

OSC1

Q1 Q2

1 3 3

Q3 Q4 Q1

4 4

TABLE 10-2: EXTERNAL CLOCK TIMING REQUIREMENTS - PIC12C508/C509

AC Characteristics Standard Operating Conditions (unless otherwise speciﬁed)

Operating Temperature 0°C ≤ T

–40°C ≤ T –40°C ≤ T

Operating Voltage V

Parameter

No.

1 T

2 Tcy 3 TosL, TosH Clock in (OSC1) Low or High Time 50* — — ns XT oscillator

4 TosR, TosF Clock in (OSC1) Rise or Fall Time — — 25* ns XT oscillator

* These parameters are characterized but not tested.

Sym Characteristic Min

FOSC

OSC

External CLKIN Frequency

Oscillator Frequency

External CLKIN Period

Oscillator Period

Instruction Cycle Time

DD range is described in Section 10.1

(2)

(3)

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.

A ≤ +70°C (commercial),

A ≤ +85°C (industrial), A ≤ +125°C (extended)

(1)

Typ

DC — 4 MHz XT osc mode DC — 200 kHz LP osc mode

0.1 — 4 MHz XT osc mode

DC — 200 kHz LP osc mode 250 — — ns EXTRC osc mode 250 — — ns XT osc mode

5 — — ms LP osc mode 250 — — ns EXTRC osc mode 250 — 10,000 ns XT osc mode

5 — — ms LP osc mode

— 4/FOSC — —

2* — — ms LP oscillator

— — 50* ns LP oscillator

Max Units Conditions

DS40139D-page 66  1998 Microchip Technology Inc.

PIC12C5XX

TABLE 10-3: CALIBRATED INTERNAL RC FREQUENCIES - PIC12C508/C509

AC Characteristics Standard Operating Conditions (unless otherwise speciﬁed)

Operating Temperature 0°C ≤ T

–40°C ≤ T –40°C ≤ T

Operating Voltage V

DD range is described in Section 10.1

A ≤ +70°C (commercial),

A ≤ +85°C (industrial), A ≤ +125°C (extended)

Parameter

No.

* These parameters are characterized but not tested.

Sym Characteristic Min*

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

Typ

(1)

Max* Units Conditions

DD = 2.5V

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.

FIGURE 10-3: I/O TIMING - PIC12C508/C509

OSC1

I/O Pin

(input)

I/O Pin

(output)

Old Value

Q2 Q3

New Value

20, 21

Note: All tests must be done with speciﬁed capacitive loads (see data sheet) 50 pF on I/O pins and CLKOUT.

 1998 Microchip Technology Inc. DS40139D-page 67

PIC12C5XX

TABLE 10-4: TIMING REQUIREMENTS - PIC12C508/C509

AC Characteristics Standard Operating Conditions (unless otherwise speciﬁed)

Operating Temperature 0°C ≤ T

–40°C ≤ T –40°C ≤ T

Operating Voltage V

DD range is described in Section 10.1

A ≤ +70°C (commercial)

A ≤ +85°C (industrial) A ≤ +125°C (extended)

Parameter

No. Sym Characteristic Min Typ

17 18

TosH2ioV

OSC1↑ (Q1 cycle) to Port out valid

(3)

TosH2ioI OSC1↑ (Q2 cycle) to Port input invalid

— — 100* ns

TBD — — ns

(1)

Max Units

(I/O in hold time)

TioV2osH Port input valid to OSC1↑

TBD — — ns

(I/O in setup time)

(3)

— 10 25** ns — 10 25** ns

20 21

TioR TioF

Port output rise time Port output fall time

* 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.

FIGURE 10-4: RESET, WATCHDOG TIMER, AND DEVICE RESET TIMER TIMING - PIC12C508/C509

DS40139D-page 68  1998 Microchip Technology Inc.

PIC12C5XX

TABLE 10-5: RESET, WATCHDOG TIMER, AND DEVICE RESET TIMER - PIC12C508/C509

AC Characteristics Standard Operating Conditions (unless otherwise speciﬁed)

Operating Temperature 0°C ≤ T

–40°C ≤ T –40°C ≤ T

Operating Voltage V

DD range is described in Section 10.1

A ≤ +70°C (commercial)

A ≤ +85°C (industrial) A ≤ +125°C (extended)

Parameter

No. Sym Characteristic Min Typ

30 31

TmcL MCLR Pulse Width (low) 2000* — — ns VDD = 5 V

Twdt Watchdog Timer Time-out Period

9* 18* 30* ms VDD = 5 V (Commercial)

(1)

Max Units Conditions

(No Prescaler)

32 34

TDRT Device Reset Timer Period

TioZ I/O Hi-impedance from MCLR Low — — 2000* ns

(2)

9* 18* 30* ms VDD = 5 V (Commercial)

* 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.

TABLE 10-6: DRT (DEVICE RESET TIMER PERIOD - PIC12C508/C509)

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 69

PIC12C5XX

FIGURE 10-5: TIMER0 CLOCK TIMINGS - PIC12C508/C509

T0CKI

40 41

TABLE 10-7: TIMER0 CLOCK REQUIREMENTS - PIC12C508/C509

AC Characteristics Standard Operating Conditions (unless otherwise speciﬁed)

Operating Temperature 0°C ≤ T

–40°C ≤ T –40°C ≤ T

Operating Voltage V

Parameter

No.

40 Tt0H T0CKI High Pulse Width - No Prescaler 0.5 TCY + 20* — — ns

41 Tt0L T0CKI Low Pulse Width - No Prescaler 0.5 TCY + 20* — — ns

42 Tt0P T0CKI Period 20 or TCY + 40*

* 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

Sym Characteristic Min Typ

- With Prescaler 10* — — ns

and are not tested.

DD range is described in Section 10.1.

A ≤ +70°C (commercial)

A ≤ +85°C (industrial) A ≤ +125°C (extended)

(1)

Max Units Conditions

— — ns Whichever is greater.

N = Prescale Value

(1, 2, 4,..., 256)

DS40139D-page 70  1998 Microchip Technology Inc.

NOTES:

PIC12C5XX

 1998 Microchip Technology Inc. DS40139D-page 71

PIC12C5XX

DS40139D-page 72  1998 Microchip Technology Inc.

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 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)

4.45

4.25

4.05

3.85

DD range). This is for information

Frequency (Mhz)

3.65

3.45

3.25

-40 25 85 125

Temperature (Deg C)

 1998 Microchip Technology Inc. DS40139D-page 73

PIC12C5XX

Frequency (Mhz)

FIGURE 11-2: CALIBRATED INTERNAL RC FREQUENCY RANGE VS. TEMPERATURE (VDD = 5.0V)

FIGURE 11-3: WDT TIMER TIME-OUT

Calibrated Internal RC Frequency Range vs Temperature (Vdd=5.0V)

PERIOD vs. VDD

WDT period (mS)

25 85

Temperature (Deg C)

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.

Max +125°C

Max +85°C

Typ +25°C

MIn –40°C

2 3 4 5 6 7

DD (Volts)

DS40139D-page 74  1998 Microchip Technology Inc.

PIC12C5XX

FIGURE 11-4: SHORT DRT PERIOD VS. VDD

1000

900

800

700

600

500

WDT period (µs)

Max +125°C

Max +85°C

400

300

Typ +25°C

200

100

MIn –40°C

2 3 4 5 6 7

DD (Volts)

FIGURE 11-5: IOH vs. VOH, VDD = 2.5 V

FIGURE 11-6: IOH vs. VOH, VDD = 5.5 V

-5

-10

-15

IOH (mA)

-20

Min +125°C

Min +85°C

-25

-30

Typ +25°C

Max –40°C

3.5 4.0 4.5

5.0 5.5

VOH (Volts)

FIGURE 11-7: IOL vs. VOL, VDD = 2.5 V

-1

-2

-3

IOH (mA)

-4

Min +125°C

-5

Min +85°C

-6

Typ +25°C

Max –40°C

-7

500m 1.0 1.5

VOH (Volts)

2.0 2.5

IOL (mA)

Max –40°C

Typ +25°C

Min +85°C

Min +125°C

250.0m 500.0m 1.0

OL (Volts)

 1998 Microchip Technology Inc. DS40139D-page 75

PIC12C5XX

FIGURE 11-8: IOL vs. VOL, VDD = 5.5 V

Max –40°C

IOL (mA)

250.0m

NOTES:

Typ +25°C

Min +85°C

Min +125°C

500.0m 750.0m 1.0

OL (Volts)

DS40139D-page 76  1998 Microchip Technology Inc.

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 Voltage on MCLR Voltage on all other pins with respect to V Total Power Dissipation Max. Current out of V Max. Current into V Input Clamp Current, I Output Clamp Current, I

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

†

DD with respect to VSS .................................................................................................................0 to +7.0 V

with respect to VSS...............................................................................................................0 to +14 V

SS ................................................................................–0.6 V to (VDD + 0.6 V)

(1)

....................................................................................................................................700 mW

SS pin...................................................................................................................................200 mA

DD pin......................................................................................................................................150 mA

IK (VI < 0 or VI > VDD) ....................................................................................................................±20 mA

OK (VO < 0 or VO > VDD) ............................................................................................................±20 mA

DIS = VDD x {IDD - ∑ IOH} + ∑ {(VDD-VOH) x IOH} + ∑(VOL x IOL)

 1998 Microchip Technology Inc. Preliminary DS40139D-page 77

PIC12C5XX

12.1 DC CHARACTERISTICS: PIC12C508A/509A (Commercial) PIC12C508A/509A (Industrial) PIC12C508A/509A (Extended)

Standard Operating Conditions (unless otherwise speciﬁed)

DC Characteristics

Power Supply Pins

Operating Temperature 0°C ≤ TA ≤ +70°C (commercial)

–40°C ≤ T –40°C ≤ T

A ≤ +85°C (industrial) A ≤ +125°C (extended)

Characteristic Sym Min

Supply Voltage V

RAM Data Retention Voltage

(2)

DD Start Voltage to ensure

VPOR VSS V See section on Power-on Reset for details

Power -on Reset

DD Rise Rate to ensure

SVDD 0.05* V/ms See section on Power-on Reset for details

Power-on Reset Supply Current

(3)

∆IWDT

Power-Down Current

(5)

(1)

Typ

DD 3.0 5.5 V FOSC = DC to 4 MHz (Commercial/

Max Units Conditions

Industrial, Extended)

VDR 1.5* V Device in SLEEP mode

XT and EXTRC options (Note 4)

IDD

— — — — —

— — —

IPD —

— —

0.6

0.6 15 19 19

3.75

0.25

0.25 2

1.4

1.4 27 35 35

OSC = 4 MHz, VDD = 5.5V

INTRC Option F

OSC = 4 MHz, VDD = 5.5V

µA

LP O

PTION, Commercial Temperature

OSC = 32 kHz, VDD = 3.0V, WDT disabled

µA

LP O

PTION, Industrial Temperature

OSC = 32 kHz, VDD = 3.0V, WDT disabled

µA

LP O

PTION, Extended Temperature

OSC = 32 kHz, VDD = 3.0V, WDT disabled

µA

8 9 4

4 5

DD = 3.0V, Commercial

µA

DD = 3.0V, Industrial

µA

DD = 3.0V, Extended

µA

VDD = 3.0V, Commercial

µA

DD = 3.0V, Industrial

µA

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

DS40139D-page 78 Preliminary  1998 Microchip Technology Inc.

DD or VSS.

PIC12C5XX

12.2 DC CHARACTERISTICS: PIC12LC508A/509A (Commercial, Industrial)

DC Characteristics Power Supply Pins

Characteristic Sym Min

Supply Voltage V

RAM Data Retention Voltage

(2)

DD Start Voltage to ensure

VPOR VSS V See section on Power-on Reset for details

Power -on Reset

DD Rise Rate to ensure

SVDD 0.05* V/ms See section on Power-on Reset for details

Power-on Reset Supply Current

(3)

∆IWDT

Standard Operating Conditions (unless otherwise speciﬁed)

Operating Temperature 0°C ≤ T

–40°C ≤ T

(1)

Typ

DD 2.5 5.5 V FOSC = DC to 4 MHz (Commercial/

Max Units Conditions

A ≤ +70°C (commercial) A ≤ +85°C (industrial)

Industrial)

VDR 1.5* V Device in SLEEP mode

XT and EXTRC options (Note 4)

IDD

— — — —

—

TBD TBD TBD TBD

TBD

TBD TBD TBD TBD

TBD

mA mA

µA µA

µA

OSC = 4 MHz, VDD = 2.5V

INTRC Option F

OSC = 4 MHz, VDD = 2.5V

LP O

PTION, Commercial Temperature

OSC = 32 kHz, VDD = 2.5V, WDT disabled

LP O

PTION, Industrial Temperature

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.

 1998 Microchip Technology Inc. Preliminary DS40139D-page 79

PIC12C5XX

12.3 DC CHARACTERISTICS: PIC12C508A/509A (Commercial, Industrial, Extended)

Standard Operating Conditions (unless otherwise speciﬁed)

Operating temperature 0˚C ≤ T

DC CHARACTERISTICS

Operating voltage V

–40˚C ≤ T –40°C ≤ T

DD range as described in DC spec Section 12.1 and

Section 12.2.

Param

Characteristic Sym Min Typ†Max Units Conditions

No.

Input Low Voltage

I/O ports V

D030 with TTL buffer VSS - 0.5V V D031 with Schmitt Trigger buffer V D032 MCLR

, GP2/T0CKI/AN2/INT

SS - 0.2VDD V

VSS - 0.2VDD V

(in EXTRC mode)

D033 OSC1 (in XT, HS and LP) V

SS - 0.3VDD V Note1

Input High Voltage

I/O ports V D040 with TTL buffer 2.0 - V D040A 0.8V D041 with Schmitt Trigger buffer 0.8V D042 MCLR

, GP2/T0CKI/AN2/INT 0.8VDD - VDD V D042A OSC1 (XT, HS and LP) 0.7V D043 OSC1 (in EXTRC mode) 0.9V D070 GPIO weak pull-up current I

IH -

DD V 4.5 ≤ VDD ≤ 5.5V DD - VDD V For VDD > 5.5V or VDD < 4.5V DD - VDD V For entire VDD range

DD - VDD V Note1 DD - VDD V

PUR 50 250 400 µA VDD = 5V, VPIN = VSS

Input Leakage Current (Notes 2, 3)

D060 I/O ports I

D061 MCLR

, GP2/T0CKI - -

IL - - +1 µA Vss ≤ VPIN ≤ VDD, Pin at hi-

(5)

D063 OSC1 - - +5 µA Vss ≤ VPIN ≤ VDD, XT, HS and LP

Output Low Voltage

D080 I/O ports/CLKOUT V

OL - - 0.6 V IOL = 8.5 mA, VDD = 4.5V,

D080A - - 0.6 V I

D083 OSC2 - - 0.6 V I

D083A - - 0.6 V I

† 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 level. 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.

A ≤ +70˚C (commercial) A ≤ +85˚C (industrial) A ≤ +125˚C (extended)

impedance

µA Vss ≤ VPIN ≤ VDD

osc conﬁguration

–40°C to +85°C

OL = 7.0 mA, VDD = 4.5V,

–40°C to +125°C

OL = 1.6 mA, VDD = 4.5V,

–40°C to +85°C

OL = 1.2 mA, VDD = 4.5V,

–40°C to +125°C

DS40139D-page 80 Preliminary  1998 Microchip Technology Inc.

PIC12C5XX

Standard Operating Conditions (unless otherwise speciﬁed)

Operating temperature 0˚C ≤ T

DC CHARACTERISTICS

Operating voltage V

–40˚C ≤ T –40°C ≤ T

DD range as described in DC spec Section 12.1 and

Section 12.2.

Param

Characteristic Sym Min Typ†Max Units Conditions

No.

Output High Voltage

D090 I/O ports/CLKOUT (Note 3) V

D090A V

D092 OSC2 V

D092A V

OH VDD - 0.7 - - V IOH = -3.0 mA, VDD = 4.5V,

DD - 0.7 - - V IOH = -2.5 mA, VDD = 4.5V,

DD - 0.7 - - V IOH = -1.3 mA, VDD = 4.5V,

DD - 0.7 - - V IOH = -1.0 mA, VDD = 4.5V,

Capacitive Loading Specs on Output Pins

D100 OSC2 pin C

D101 All I/O pins and OSC2 C

OSC2 - - 15 pF In XT, HS and LP modes when

IO - - 50 pF

† 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 level. 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.

A ≤ +70˚C (commercial) A ≤ +85˚C (industrial) A ≤ +125˚C (extended)

–40°C to +85°C

–40°C to +125°C

–40°C to +85°C

–40°C to +125°C

external clock is used to drive OSC1.

 1998 Microchip Technology Inc. Preliminary DS40139D-page 81

PIC12C5XX

12.4 DC CHARACTERISTICS: PIC12LC508A/509A (Commercial, Industrial)

Standard Operating Conditions (unless otherwise speciﬁed)

Operating temperature 0˚C ≤ T

DC CHARACTERISTICS

Operating voltage V

–40˚C ≤ T

DD range as described in DC spec Section 12.1 and

Section 12.2.

Param

Characteristic Sym Min Typ†Max Units Conditions

No.

Input Low Voltage

I/O ports V

D030 with TTL buffer VSS - 0.5V V D031 with Schmitt Trigger buffer V D032 MCLR

, GP2/T0CKI/AN2/INT

SS - 0.2VDD V

VSS - 0.2VDD V

(in EXTRC mode)

D033 OSC1 (in XT, HS and LP) V

SS - 0.3VDD V Note1

Input High Voltage

I/O ports V D040 with TTL buffer TBD - V D040A TBD - V D041 with Schmitt Trigger buffer 0.8V D042 MCLR

, GP2/T0CKI/AN2/INT 0.8VDD - VDD V D042A OSC1 (XT, HS and LP) 0.7V D043 OSC1 (in EXTRC mode) 0.9V D070 GPIO weak pull-up current I

IH -

DD V 4.5 ≤ VDD ≤ 5.5V DD V For VDD > 5.5V or VDD < 4.5V

DD - VDD V For entire VDD range

DD - VDD V Note1 DD - VDD V

PUR 50 250 400 µA VDD = 5V, VPIN = VSS

Input Leakage Current (Notes 2, 3)

D060 I/O ports I

D061 MCLR

, GP2/T0CKI TBD TBD TBD µA Vss ≤ VPIN ≤ VDD

IL TBD TBD TBD µA Vss ≤ VPIN ≤ VDD, Pin at hi-

D063 OSC1 TBD TBD TBD µA Vss ≤ VPIN ≤ VDD, XT, HS and LP

Output Low Voltage

D080 I/O ports/CLKOUT V

OL - - TBD V IOL = 8.5 mA, VDD = 4.5V,

D080A - - 0.6 V I

D083 OSC2 - - 0.6 V I

D083A - - 0.6 V I

† 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 level. 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.

A ≤ +70˚C (commercial)

A ≤ +85˚C (industrial)

impedance

osc conﬁguration

–40°C to +85°C

OL = 7.0 mA, VDD = 4.5V,

–40°C to +125°C

OL = 1.6 mA, VDD = 4.5V,

–40°C to +85°C

OL = 1.2 mA, VDD = 4.5V,

–40°C to +125°C

DS40139D-page 82 Preliminary  1998 Microchip Technology Inc.

StandarDat LoatemperIn X5.5483.70(Datureandar)502.111 0 0˚C o +85∞ VDD∞∞

DC CHARACTERISTICS

Output High Voltage

D090 I/O ports/CLKOUT (Note 3) V

D090A V

D092 OSC2 V

D092A V

Capacitive Loading Specs on Output Pins

D100 OSC2 pin C

D101 All I/O pins and OSC2 C

OH VDD - 0.7 - - V IOH = -3.0 mA, VDD = 4.5V,

OSC2 - - 15 pF In XT, HS and LP modes when

IO - - 50 pF

PIC12C5XX

–40°C to +85°C

DD - 0.7 - - V IOH = -2.5 mA, VDD = 4.5V,

–40°C to +125°C

DD - 0.7 - - V IOH = -1.3 mA, VDD = 4.5V,

–40°C to +85°C

DD - 0.7 - - V IOH = -1.0 mA, VDD = 4.5V,

–40°C to +125°C

external clock is used to drive OSC1.

 1998 Microchip Technology Inc. Preliminary DS40139D-page 83

PIC12C5XX

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 Ω 25 42K 48K 63K Ω 85 42K 49K 63K Ω

125 50K 55K 63K Ω

5.5 –40 15K 17K 20K Ω 25 18K 20K 23K Ω 85 19K 22K 25K Ω

125 22K 24K 28K Ω

GP3

2.5 –40 285K 346K 417K Ω 25 343K 414K 532K Ω 85 368K 457K 532K Ω

125 431K 504K 593K Ω

5.5 –40 247K 292K 360K Ω 25 288K 341K 437K Ω 85 306K 371K 448K Ω

125 351K 407K 500K Ω

* These parameters are characterized but not tested.

DS40139D-page 84 Preliminary  1998 Microchip Technology Inc.

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

F Frequency T Time Lowercase subscripts (pp) and their meanings:

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:

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

VSS

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

 1998 Microchip Technology Inc. Preliminary DS40139D-page 85

PIC12C5XX

12.6 Timing Diagrams and Speciﬁcations FIGURE 12-2: EXTERNAL CLOCK TIMING - PIC12C508A/C509A

OSC1

Q1 Q2

1 3 3

Q3 Q4 Q1

4 4

TABLE 12-2: EXTERNAL CLOCK TIMING REQUIREMENTS - PIC12C508A/C509A

AC Characteristics Standard Operating Conditions (unless otherwise speciﬁed)

Operating Temperature 0°C ≤ T

–40°C ≤ T –40°C ≤ T

Operating Voltage V

Parameter

No.

1 T

2 Tcy 3 TosL, TosH Clock in (OSC1) Low or High Time 50* — — ns XT oscillator

4 TosR, TosF Clock in (OSC1) Rise or Fall Time — — 25* ns XT oscillator

* These parameters are characterized but not tested.

Sym Characteristic Min

FOSC

OSC

External CLKIN Frequency

Oscillator Frequency

External CLKIN Period

Oscillator Period

Instruction Cycle Time

DD range is described in Section 12.1

(2)

(3)

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-

3: Instruction cycle period (T

CY) equals four times the input oscillator time base period.

A ≤ +70°C (commercial),

A ≤ +85°C (industrial), A ≤ +125°C (extended)

(1)

Typ

DC — 4 MHz XT osc mode DC — 200 kHz LP osc mode DC — 4 MHz EXTRC osc mode

0.1 — 4 MHz XT osc mode DC — 200 kHz LP osc mode

250 — — ns XT osc mode

5 — — ms LP osc mode 250 — — ns EXTRC osc mode 250 — 10,000 ns XT osc mode

5 — — ms LP osc mode

— 4/FOSC — —

2* — — ms LP oscillator

— — 50* ns LP oscillator

Max Units Conditions

DS40139D-page 86 Preliminary  1998 Microchip Technology Inc.

PIC12C5XX

TABLE 12-3: CALIBRATED INTERNAL RC FREQUENCIES - PIC12C508A/C509A

AC Characteristics Standard Operating Conditions (unless otherwise speciﬁed)

Operating Temperature 0°C ≤ T

–40°C ≤ T –40°C ≤ T

Operating Voltage V

DD range is described in Section 10.1

A ≤ +70°C (commercial),

A ≤ +85°C (industrial), A ≤ +125°C (extended)

Parameter

No.

* These parameters are characterized but not tested.

Sym Characteristic Min*

Internal Calibrated RC Frequency TBD 4.00 TBD MHz VDD = 5.0V

Internal Calibrated RC Frequency

TBD 4.00 TBD MHz V

Typ

(1)

Max* Units Conditions

DD = 2.5V

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.

 1998 Microchip Technology Inc. Preliminary DS40139D-page 87

PIC12C5XX

FIGURE 12-3: I/O TIMING - PIC12C508A/C509A

Q2 Q3

OSC1

I/O Pin

(input)

I/O Pin

(output)

Note: All tests must be done with speciﬁed capacitive loads (see data sheet) 50 pF on I/O pins and CLKOUT.

Old Value

20, 21

TABLE 12-4: TIMING REQUIREMENTS - PIC12C508A/C509A

AC Characteristics Standard Operating Conditions (unless otherwise speciﬁed)

Operating Temperature 0°C ≤ T

–40°C ≤ T –40°C ≤ T

Operating Voltage V

DD range is described in Section 12.1

A ≤ +70°C (commercial)

A ≤ +85°C (industrial) A ≤ +125°C (extended)

New Value

Parameter

No. Sym Characteristic Min Typ

17 18

TosH2ioV

OSC1↑ (Q1 cycle) to Port out valid

(3)

TosH2ioI OSC1↑ (Q2 cycle) to Port input invalid

— — 100* ns

TBD — — ns

(1)

Max Units

(I/O in hold time)

TioV2osH Port input valid to OSC1↑

TBD — — ns

(I/O in setup time)

(3)

— 10 25** ns — 10 25** ns

20 21

TioR TioF

Port output rise time Port output fall time

* 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.

DS40139D-page 88 Preliminary  1998 Microchip Technology Inc.

PIC12C5XX

FIGURE 12-4: RESET, WATCHDOG TIMER, AND DEVICE RESET TIMER TIMING -

PIC12C508A/C509A

VDD

MCLR

Internal

POR

DRT

Timeout

(Note 2)

Internal

RESET

Watchdog

Timer

RESET

I/O pin (Note 1)

Note 1: I/O pins must be taken out of hi-impedance mode by enabling the output drivers in software. 2: Runs in MCLR or WDT reset only in XT and LP modes.

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

–40°C ≤ T –40°C ≤ T

Operating Voltage V

DD range is described in Section 12.1

Parameter

No. Sym Characteristic Min Typ

30 31

TmcL MCLR Pulse Width (low) 2000* — — ns VDD = 5 V

Twdt Watchdog Timer Time-out Period

(No Prescaler)

32 34

TDRT Device Reset Timer Period

TioZ I/O Hi-impedance from MCLR Low — — 2000* ns

(2)

* 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.

A ≤ +70°C (commercial)

A ≤ +85°C (industrial) A ≤ +125°C (extended)

(1)

Max Units Conditions

9* 18* 30* ms VDD = 5 V (Commercial)

 1998 Microchip Technology Inc. Preliminary DS40139D-page 89

PIC12C5XX

TABLE 12-6: DRT (DEVICE RESET TIMER PERIOD) - PIC12C508A/C509A

Oscillator Conﬁguration POR Reset Subsequent Resets

IntRC & ExtRC 18 ms (typical) 300 µs (typical) XT & LP 18 ms (typical) 18 ms (typical)

FIGURE 12-5: TIMER0 CLOCK TIMINGS - PIC12C508A/C509A

T0CKI

40 41

TABLE 12-7: TIMER0 CLOCK REQUIREMENTS - PIC12C508A/C509A

AC Characteristics Standard Operating Conditions (unless otherwise speciﬁed)

Operating Temperature 0°C ≤ T

–40°C ≤ T –40°C ≤ T

Operating Voltage V

Parameter

No.

40 Tt0H T0CKI High Pulse Width - No Prescaler 0.5 TCY + 20* — — ns

41 Tt0L T0CKI Low Pulse Width - No Prescaler 0.5 TCY + 20* — — ns

42 Tt0P T0CKI Period 20 or TCY + 40*

* 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

Sym Characteristic Min Typ

- With Prescaler 10* — — ns

and are not tested.

DD range is described in Section 12.1.

A ≤ +70°C (commercial)

A ≤ +85°C (industrial) A ≤ +125°C (extended)

(1)

Max Units Conditions

— — ns Whichever is greater.

N = Prescale Value

(1, 2, 4,..., 256)

DS40139D-page 90 Preliminary  1998 Microchip Technology Inc.

PIC12C5XX

13.0 DC AND AC CHARACTERISTICS - PIC12C508A/PIC12C509A/ PIC12LC508A/PIC12LC509A

FIGURE 13-1: CALIBRATED INTERNAL RC FREQUENCY RANGE VS. TEMPERATURE (VDD = 5.0V)

(INTERNAL RC IS CALIBRATED TO 25°C, 5.0V)

Not available at this time.

DD range). This is for information

FIGURE 13-2: CALIBRATED INTERNAL RC FREQUENCY RANGE VS. TEMPERATURE (V

(INTERNAL RC IS CALIBRATED TO 25°C, 5.0V)

Not available at this time.

DD = 2.5V)

 1998 Microchip Technology Inc. Preliminary DS40139D-page 91

PIC12C5XX

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

WDT period (mS)

2 3 4 5 6 7

DD (Volts)

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

WDT period (µs)

400

300

200

100

2 3 4 5 6 7

DD (Volts)

Max +125°C

Max +85°C

Typ +25°C

MIn –40°C

DS40139D-page 92 Preliminary  1998 Microchip Technology Inc.

PIC12C5XX

FIGURE 13-5: IOH vs. VOH, VDD = 2.5 V

-5

TBD

-10

-15

IOH (mA)

-20

-25

-30

1.5 2.0 2.5 3.0 3.5

VOH (Volts)

FIGURE 13-7: IOL vs. VOL, VDD = 2.5 V

TBD

IOL (mA)

500.0m 750.0m 1.0

OL (Volts)

FIGURE 13-6: IOH vs. VOH, VDD = 3.5 V

-5

-10

Min +125°C

-15

IOH (mA)

Min +85°C

Typ +25°C

-20

Max –40°C

-25

-30

1.5 2.0 2.5 3.0 3.5

VOH (Volts)

FIGURE 13-8: I

IOL (mA)

OL vs. VOL, VDD = 3.5 V

Max –40°C

Typ +25°C

Min +85°C

Min +125°C

500.0m 750.0m 1.0

OL (Volts)

 1998 Microchip Technology Inc. Preliminary DS40139D-page 93

PIC12C5XX

DS40139D-page 94 Preliminary  1998 Microchip Technology Inc.

14.0 PACKAGING INFORMATION

14.1 Package Marking Information

8-Lead PDIP (300 mil)

PIC12C5XX

Example

XXXXXXXX XXXXXCDE

AABB

8-Lead SOIC (150 mil)

XXXXXXX

XXXX

8-Lead SOIC (208 mil)

XXXXXXX XXXXXXX AABBCDE

8-Lead Windowed Ceramic Side Brazed (300 mil)

XXX

12C508A 04I/PSAZ

9825

Example

C508A

9825

Example

12C508A 04I/SM 9824SAZ

Example

XXXXXX

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.

12C508A

 1998 Microchip Technology Inc. DS40139D-page 95

PIC12C5XX

Package Type: K04-018 8-Lead Plastic Dual In-line (P) – 300 mil

Units Dimension Limits PCB Row Spacing Number of Pins Pitch Lower Lead Width Upper Lead Width Shoulder Radius Lead Thickness Top to Seating Plane Top of Lead to Seating Plane Base to Seating Plane Tip to Seating Plane Package Length Molded Package Width Radius to Radius Width Overall Row Spacing Mold Draft Angle Top Mold Draft Angle Bottom

* 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.”

n p B B1 R c A A1 A2 L D E E1 eB

α β

†

‡

MIN

0.014

0.055

0.000

0.006

0.140

0.060

0.005

0.120

0.355

0.245

0.267

0.310

INCHES*

5 5

0.300

0.100

0.018

0.060

0.005

0.012

0.150

0.080

0.020

0.130

0.370

0.250

0.280

10 10

MILLIMETERS

15 15

MINNOM

0.36

1.40

0.00

0.20

3.56

1.52

0.13

3.05

9.02

6.22

6.78

5 5

MAX

0.022

0.065

0.010

0.015

0.160

0.100

0.035

0.140

0.385

0.260

0.292

0.3800.342

NOM MAX

7.62 8

2.54

0.46

1.52

0.13

0.29

3.81

2.03

0.51

3.30

9.40

6.35

7.10

10 10

0.56

1.65

0.25

0.38

4.06

2.54

0.89

3.56

9.78

6.60

7.42

9.658.677.87 15 15

DS40139D-page 96  1998 Microchip Technology Inc.

PIC12C5XX

Package Type: K04-057 8-Lead Plastic Small Outline (SN) – Narrow, 150 mil

Units

Pitch Number of Pins Overall Pack. Height Shoulder Height Standoff Molded Package Length Molded Package Width Outside Dimension Chamfer Distance Shoulder Radius Gull Wing Radius Foot Length Foot Angle Radius Centerline Lead Thickness Lower Lead Width Mold Draft Angle Top Mold Draft Angle Bottom

n 1

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.”

‡

p n A A1 A2 D E E1 X R1 R2 L

L1 c B

α β

‡

†

MINDimension Limits

0.054

0.027

0.004

0.189

0.150

0.229

0.010

0.005

0.011 0

0.000

0.008

0.014 0 0

INCHES* MILLIMETERS

0.050 8

0.061

0.035

0.007

0.193

0.154

0.237

0.015

0.005

0.016

0.005

0.009

0.017

12 12

0.069

0.044

0.010

0.196

0.157

0.244

0.020

0.010

0.021

4 8

0.010

0.020 15 15

1.37

0.69

0.10

4.80

3.81

5.82

0.25

0.13

0.28

0.00

0.19

0.36

0 0

1.27

1.56

0.90

0.18

4.89

6.01

0.38

0.13

0.41

0.13

0.22

0.43 12 12

MAXNOMMINMAXNOM

1.75

1.11

0.25

4.98

3.993.90

6.20

0.51

0.25

0.53

0.25

0.51 15 15

 1998 Microchip Technology Inc. DS40139D-page 97

PIC12C5XX

Package Type: K04-056 8-Lead Plastic Small Outline (SM) – Medium, 208 mil

n 1

Units Dimension Limits Pitch Number of Pins Overall Pack. Height Shoulder Height Standoff Molded Package Length Molded Package Width Outside Dimension Shoulder Radius Gull Wing Radius Foot Length Foot Angle Radius Centerline Lead Thickness Lower Lead Width Mold Draft Angle Top Mold Draft Angle Bottom

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.”

‡

p n A A1 A2 D E E1 R1 R2 L

L1 c B

α β

MIN

0.070

0.037

‡ ‡

†

0.002

0.200

0.203

0.300

0.005

0.011

0.010

0.014

INCHES*

0 0

NOM

0.050

0.074

0.042

0.005

0.205

0.208

0.313

0.005

0.016

0.015

0.017

MAX NOM

0.079

0.048

0.009

0.210

0.213

0.325

0.010

0.021

4 8

0.020

0.0100.0090.008

0.020 12 12

MIN MAX

15 15

MILLIMETERS

1.78

0.94

0.05

5.08

5.16

7.62

0.13

0.28 0

0.25

0.36 0 0

1.27

1.89

1.08

0.14

5.21

5.28

7.94

0.13

0.41

0.38

0.43 12 12

2.00

1.21

0.22

5.33

5.41

8.26

0.25

0.53

0.51

0.250.220.19

0.51 15 15

DS40139D-page 98  1998 Microchip Technology Inc.

PIC12C5XX

Package Type: K04-084 8-Lead Ceramic Side Brazed Dual In-line with Window (JW) – 300 mil

Units Dimension Limits PCB Row Spacing Number of Pins Pitch Lower Lead Width Upper Lead Width Lead Thickness Top to Seating Plane Top of Body to Seating Plane Base to Seating Plane Tip to Seating Plane Package Length Package Width Overall Row Spacing Window Diameter Lid Length Lid Width

* Controlling Parameter.

n p B B1 c A A1 A2 L D E eB W T U

MIN

0.098

0.016

0.050

0.008

0.145

0.103

0.025

0.130

0.510

0.280

0.310

0.161

0.440

0.260

INCHES*

NOM

0.300 8

0.100

0.018

0.055

0.010

0.165

0.123

0.035

0.140

0.520

0.290

0.338

0.166

0.450

0.270

MAX

0.102

0.020

0.060

0.012

0.185

0.143

0.045

0.150

0.530

0.300

0.365

0.171

0.460

0.280

MIN

2.49

0.41

1.27

0.20

3.68

2.62

0.64

3.30

12.95

7.11

7.87

4.09

11.18

6.60

MILLIMETERS

NOM

7.62 8

2.54

0.46

1.40

0.25

4.19

3.12

0.89

3.56

13.21

7.37

8.57

4.22

11.43

6.86

MAX

2.59

0.51

1.52

0.30

4.70

3.63

1.14

3.81

13.46

7.62

9.27

4.34

11.68

7.11

 1998 Microchip Technology Inc. DS40139D-page 99

PIC12C5XX

DS40139D-page 100  1998 Microchip Technology Inc.

MICROCHIP PIC12C5XX User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

1.0 GENERAL DESCRIPTION

1.1 Applications

2.0 PIC12C5XX DEVICE VARIETIES

3.0 ARCHITECTURAL OVERVIEW

4.0 MEMORY ORGANIZATION

4.2.1 GENERAL PURPOSE REGISTER FILE The general purpose register ﬁle is accessed either

4.2.2 SPECIAL FUNCTION REGISTERS

4.3 STATUS Register

4.4 OPTION Register

4.5 OSCCAL Register

4.6 Program Counter

4.6.1 EFFECTS OF RESET The Program Counter is set upon a RESET, which

4.7 Stack

5.0 I/O PORT

5.1 GPIO

5.2 TRIS Register

5.3 I/O Interfacing

5.4 I/O Programming Considerations

5.4.1 BI-DIRECTIONAL I/O PORTS

6.0 TIMER0 MODULE AND TMR0 REGISTER

6.1 Using Timer0 with an External Clock

6.1.1 EXTERNAL CLOCK SYNCHRONIZATION

6.1.2 TIMER0 INCREMENT DELAY Since the prescaler output is synchronized with the

6.1.3 OPTION REGISTER EFFECT ON GP2 TRIS If the option register is set to read TIMER0 from the pin,

6.2 Prescaler

6.2.1 SWITCHING PRESCALER ASSIGNMENT The prescaler assignment is fully under software control

7.0 SPECIAL FEATURES OF THE CPU

7.2.1 OSCILLATOR TYPES The PIC12C5XX can be operated in four different

7.2.3 EXTERNAL CRYSTAL OSCILLATOR CIRCUIT

7.2.4 EXTERNAL RC OSCILLATOR For timing insensitive applications, the RC device

7.2.5 INTERNAL 4 MHz RC OSCILLATOR The internal RC oscillator provides a ﬁxed 4 MHz (nom-

7.3 RESET

7.3.1 MCLR ENABLE This conﬁguration bit when unprogrammed (left in the

7.5 Device Reset Timer (DRT)

7.6 Watchdog Timer (WDT)

7.6.1 WDT PERIOD The WDT has a nominal time-out period of 18 ms,

7.6.2 WDT PROGRAMMING CONSIDERATIONS The CLRWDT instruction clears the WDT and the

7.9 Power-Down Mode (SLEEP)

SLEEP instruction. If enabled, the Watchdog Timer will be cleared but

7.9.2 WAKE-UP FROM SLEEP The device can wake-up from SLEEP through one of

7.11 ID Locations

7.12 In-Circuit Serial Programming

8.0 INSTRUCTION SET SUMMARY

9.0 DEVELOPMENT SUPPORT

9.1 Development Tools

9.4 PRO MATE II: Universal Programmer

9.6 SIMICE Entry-Level Hardware Simulator

9.11 Assembler (MPASM)

9.12 Software Simulator (MPLAB-SIM)

9.13 MPLAB-C17 Compiler

14.0 PACKAGING INFORMATION

14.1 Package Marking Information