MICROCHIP PIC16F505-E/ST

PIC12F508/509/16F505
Data Sheet
8/14-Pin, 8-Bit Flash Microcontrollers
*8-bit, 8-pin Devices Protected by Microchip’s Low Pin Count Patent: U.S. Patent No. 5,847,450. Additional U.S. and
foreign patents and applications may be issued or pending.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C
Note the following details of the code protection feature on Microchip devices:
•
Microchip products meet the specification contained in their particular Microchip Data Sheet.
•
Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the
intended manner and under normal conditions.
•
There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our
knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data
Sheets. Most likely, the person doing so is engaged in theft of intellectual property.
•
Microchip is willing to work with the customer who is concerned about the integrity of their code.
•
Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not
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Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our
products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts
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Information contained in this publication regarding device
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Trademarks
The Microchip name and logo, the Microchip logo, Accuron,
dsPIC, KEELOQ, KEELOQ logo, microID, MPLAB, PIC,
PICmicro, PICSTART, PRO MATE, PowerSmart, rfPIC, and
SmartShunt are registered trademarks of Microchip
Technology Incorporated in the U.S.A. and other countries.
AmpLab, FilterLab, Linear Active Thermistor, Migratable
Memory, MXDEV, MXLAB, PS logo, SEEVAL, SmartSensor
and The Embedded Control Solutions Company are
registered trademarks of Microchip Technology Incorporated
in the U.S.A.
Analog-for-the-Digital Age, Application Maestro, CodeGuard,
dsPICDEM, dsPICDEM.net, dsPICworks, ECAN,
ECONOMONITOR, FanSense, FlexROM, fuzzyLAB,
In-Circuit Serial Programming, ICSP, ICEPIC, Mindi, MiWi,
MPASM, MPLAB Certified logo, MPLIB, MPLINK, PICkit,
PICDEM, PICDEM.net, PICLAB, PICtail, PowerCal,
PowerInfo, PowerMate, PowerTool, REAL ICE, rfLAB,
rfPICDEM, Select Mode, Smart Serial, SmartTel, Total
Endurance, UNI/O, WiperLock and ZENA are trademarks of
Microchip Technology Incorporated in the U.S.A. and other
countries.
SQTP is a service mark of Microchip Technology Incorporated
in the U.S.A.
All other trademarks mentioned herein are property of their
respective companies.
© 2007, Microchip Technology Incorporated, Printed in the
U.S.A., All Rights Reserved.
Printed on recycled paper.
Microchip received ISO/TS-16949:2002 certification for its worldwide
headquarters, design and wafer fabrication facilities in Chandler and
Tempe, Arizona, Gresham, Oregon and Mountain View, California. The
Company’s quality system processes and procedures are for its PIC®
MCUs and dsPIC® DSCs, KEELOQ® code hopping devices, Serial
EEPROMs, microperipherals, nonvolatile memory and analog
products. In addition, Microchip’s quality system for the design and
manufacture of development systems is ISO 9001:2000 certified.
DS41236C-page ii
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
8/14-Pin, 8-Bit Flash Microcontroller
Devices Included In This Data Sheet:
• PIC12F508
• PIC12F509
• PIC16F505
High-Performance RISC CPU:
• Only 33 single-word instructions to learn
• All single-cycle instructions except for program
branches, which are two-cycle
• 12-bit wide instructions
• 2-level deep hardware stack
• Direct, Indirect and Relative Addressing modes
for data and instructions
• 8-bit wide data path
• 8 Special Function Hardware registers
• Operating speed:
- DC – 20 MHz clock input (PIC16F505 only)
- DC – 200 ns instruction cycle (PIC16F505
only)
- DC – 4 MHz clock input
- DC – 1000 ns instruction cycle
Special Microcontroller Features:
• 4 MHz precision internal oscillator:
- Factory calibrated to ±1%
• In-Circuit Serial Programming™ (ICSP™)
• In-Circuit Debugging (ICD) support
• Power-on Reset (POR)
• Device Reset Timer (DRT)
• Watchdog Timer (WDT) with dedicated on-chip
RC oscillator for reliable operation
• Programmable code protection
• Multiplexed MCLR input pin
• Internal weak pull-ups on I/O pins
• Power-saving Sleep mode
• Wake-up from Sleep on pin change
• Selectable oscillator options:
- INTRC: 4 MHz precision Internal oscillator
- EXTRC: External low-cost RC oscillator
- XT:
Standard crystal/resonator
- HS:
High-speed crystal/resonator
(PIC16F505 only)
© 2007 Microchip Technology Inc.
- LP:
- EC:
Power-saving, low-frequency crystal
High-speed external clock input
(PIC16F505 only)
Low-Power Features/CMOS Technology:
• Operating Current:
- < 350 μA @ 2V, 4 MHz
• Standby Current:
- 100 nA @ 2V, typical
• Low-power, high-speed Flash technology:
- 100,000 Flash endurance
- > 40 year retention
• Fully static design
• Wide operating voltage range: 2.0V to 5.5V
• Wide temperature range:
- Industrial: -40°C to +85°C
- Extended: -40°C to +125°C
Peripheral Features (PIC12F508/509):
• 6 I/O pins:
- 5 I/O pins with individual direction control
- 1 input only pin
- High current sink/source for direct LED drive
- Wake-on-change
- Weak pull-ups
• 8-bit real-time clock/counter (TMR0) with 8-bit
programmable prescaler
Peripheral Features (PIC16F505):
• 12 I/O pins:
- 11 I/O pins with individual direction control
- 1 input only pin
- High current sink/source for direct LED drive
- Wake-on-change
- Weak pull-ups
• 8-bit real-time clock/counter (TMR0) with 8-bit
programmable prescaler
Preliminary
DS41236C-page 1
PIC12F508/509/16F505
Pin Diagrams
PDIP, SOIC, MSOP
14
VSS
RB5/OSC1/CLKIN
2
13
RB0/ICSPDAT
RB4/OSC2/CLKOUT
3
12
RB1/ICSPCLK
RB3/MCLR/VPP
11
RB2
RC5/T0CKI
4
5
10
RC0
RC4
6
9
RC1
RC3
7
8
RC2
PIC16F505
1
VDD
VDD
PIC12F508/509
PDIP, SOIC, TSSOP
1
GP5/OSC1/CLKIN
2
GP4/OSC2
3
GP3/MCLR/VPP
4
8
VSS
7
GP0/ICSPDAT
6
GP1/ICSPCLK
5
GP2/T0CKI
VDD
1
GP5/OSC1/CLKIN
2
GP4/OSC2
3
GP3/MCLR/VPP
4
PIC12F508/509
DFN
8
VSS
7
GP0/ICSPDAT
6
GP1/ICSPCLK
5
GP2/T0CKI
Program Memory
Data Memory
Flash (words)
SRAM (bytes)
PIC12F508
512
25
PIC12F509
1024
PIC16F505
1024
I/O
Timers
8-bit
6
1
41
6
1
72
12
1
Device
DS41236C-page 2
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
Table of Contents
1.0 General Description...................................................................................................................................................................... 5
2.0 PIC12F508/509/16F505 Device Varieties ................................................................................................................................... 7
3.0 Architectural Overview ................................................................................................................................................................. 9
4.0 Memory Organization ................................................................................................................................................................. 15
5.0 I/O Port ....................................................................................................................................................................................... 29
6.0 Timer0 Module and TMR0 Register ........................................................................................................................................... 33
7.0 Special Features Of The CPU.................................................................................................................................................... 39
8.0 Instruction Set Summary ............................................................................................................................................................ 55
9.0 Development Support................................................................................................................................................................. 63
10.0 Electrical Characteristics ............................................................................................................................................................ 67
11.0 DC and AC Characteristics Graphs and Charts ......................................................................................................................... 79
12.0 Packaging Information................................................................................................................................................................ 81
Index .................................................................................................................................................................................................... 92
The Microchip Web Site ....................................................................................................................................................................... 95
Customer Change Notification Service ................................................................................................................................................ 95
Customer Support ................................................................................................................................................................................ 95
Reader Response ................................................................................................................................................................................ 96
Product Identification System .............................................................................................................................................................. 97
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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, describing minor operational differences from the data sheet and recommended workarounds, may exist for current
devices. As device/documentation issues become known to us, we will publish an errata sheet. The errata will specify the revision
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To determine if an errata sheet exists for a particular device, please check with one of the following:
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© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 3
PIC12F508/509/16F505
NOTES:
DS41236C-page 4
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
1.0
GENERAL DESCRIPTION
1.1
The PIC12F508/509/16F505 devices from Microchip
Technology are low-cost, high-performance, 8-bit, fullystatic, Flash-based CMOS microcontrollers. They
employ a RISC architecture with only 33 single-word/
single-cycle instructions. All instructions are single
cycle (200 μs) except for program branches, which
take two cycles. The PIC12F508/509/16F505 devices
deliver performance an order of magnitude higher than
their competitors in the same price category. The 12-bit
wide instructions are highly symmetrical, resulting in a
typical 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.
Applications
The PIC12F508/509/16F505 devices fit in applications
ranging from personal care appliances and security
systems to low-power remote transmitters/receivers.
The Flash technology makes customizing application
programs (transmitter codes, appliance settings,
receiver frequencies, etc.) extremely fast and convenient. The small footprint packages, for through hole or
surface mounting, make these microcontrollers perfect
for applications with space limitations. Low cost, low
power, high performance, ease of use and I/O flexibility
make the PIC12F508/509/16F505 devices very versatile even in areas where no microcontroller use has
been considered before (e.g., timer functions, logic and
PLDs in larger systems and coprocessor applications).
The PIC12F508/509/16F505 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 (six on the PIC16F505), including
INTRC Internal Oscillator mode and the power-saving
LP (Low-Power) Oscillator mode. Power-saving Sleep
mode, Watchdog Timer and code protection features
improve system cost, power and reliability.
The PIC12F508/509/16F505 devices are available in
the cost-effective Flash programmable version, which
is suitable for production in any volume. The customer
can take full advantage of Microchip’s price leadership
in Flash programmable microcontrollers, while
benefiting from the Flash programmable flexibility.
The PIC12F508/509/16F505 products are supported
by a full-featured macro assembler, a software simulator, an in-circuit emulator, a ‘C’ compiler, a low-cost
development programmer and a full featured programmer. All the tools are supported on IBM® PC and
compatible machines.
TABLE 1-1:
PIC12F508/509/16F505 DEVICES
PIC12F508
PIC12F509
PIC16F505
Clock
Maximum Frequency of Operation (MHz)
4
4
20
Memory
Flash Program Memory
512
1024
1024
Data Memory (bytes)
25
41
72
TMR0
TMR0
TMR0
Yes
Yes
Yes
I/O Pins
5
5
11
Input Pins
1
1
1
Internal Pull-ups
Yes
Yes
Yes
In-Circuit Serial Programming
Yes
Yes
Yes
Number of Instructions
33
33
33
8-pin PDIP, SOIC,
MSOP
8-pin PDIP, SOIC,
MSOP
14-pin PDIP, SOIC,
TSSOP
Peripherals
Timer Module(s)
Wake-up from Sleep on Pin Change
Features
Packages
The PIC12F508/509/16F505 devices have Power-on Reset, selectable Watchdog Timer, selectable code-protect, high I/O current
capability and precision internal oscillator.
The PIC12F508/509/16F505 device uses serial programming with data pin RB0/GP0 and clock pin RB1/GP1.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 5
PIC12F508/509/16F505
NOTES:
DS41236C-page 6
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
2.0
PIC12F508/509/16F505 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 PIC12F508/509/16F505 Product Identification
System at the back of this data sheet to specify the
correct part number.
2.1
2.2
Serialized Quick Turn
ProgrammingSM (SQTPSM) Devices
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.
Quick Turn Programming (QTP)
Devices
Microchip offers a QTP programming service for
factory production orders. This service is made
available for users who choose not to program
medium-to-high quantity units and whose code
patterns have stabilized. The devices are identical to
the Flash devices but with all Flash locations and fuse
options already programmed by the factory. Certain
code and prototype verification procedures do apply
before production shipments are available. Please
contact your local Microchip Technology sales office for
more details.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 7
PIC12F508/509/16F505
NOTES:
DS41236C-page 8
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
3.0
ARCHITECTURAL OVERVIEW
The high performance of the PIC12F508/509/16F505
devices can be attributed to a number of architectural
features commonly found in RISC microprocessors.
To begin with, the PIC12F508/509/16F505 devices
use a Harvard architecture in which program and data
are accessed on separate buses. This improves
bandwidth over traditional von Neumann architectures 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 (200 ns @ 20 MHz, 1 μs @
4 MHz) except for program branches.
Table 3-1 below lists program memory (Flash) and data
memory (RAM) for the PIC12F508/509/16F505
devices.
TABLE 3-1:
The PIC12F508/509/16F505 devices contain 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, one
operand is typically 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 borrow and digit borrow out bit, respectively, in subtraction. See the SUBWF and ADDWF
instructions for examples.
A simplified block diagram is shown in Figure 3-2, with
the corresponding device pins described in Table 3-3.
PIC12F508/509/16F505
MEMORY
Memory
Device
Program
Data
PIC12F508
512 x 12
25 x 8
PIC12F509
1024 x 12
41 x 8
PIC16F505
1024 x 12
72 x 8
The PIC12F508/509/16F505 devices can directly or
indirectly address its register files and data memory. All
Special Function Registers (SFR), including the PC,
are mapped in the data memory. The PIC12F508/509/
16F505 devices have 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
PIC12F508/509/16F505 devices simple, yet efficient.
In addition, the learning curve is reduced significantly.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 9
PIC12F508/509/16F505
FIGURE 3-1:
PIC12F508/509 BLOCK DIAGRAM
12
Flash
512 x 12 or
1024 x 12
Program
Memory
8
Data Bus
Program Counter
GP0/ISCPDAT
GP1/ISCPCLK
GP2/T0CKI
GP3/MCLR/VPP
GP4/OSC2
GP5/OSC1/CLKIN
RAM
25 x 8 or
41 x 8
File
Registers
Stack 1
Stack 2
Program 12
Bus
RAM Addr
GPIO
9
Addr MUX
Instruction Reg
Direct Addr
5
5-7
Indirect
Addr
FSR Reg
Status Reg
8
3
MUX
Device Reset
Timer
Instruction
Decode &
Control
OSC1/CLKIN
OSC2
Timing
Generation
Internal RC
OSC
ALU
Power-on
Reset
8
Watchdog
Timer
W Reg
Timer0
MCLR
VDD, VSS
DS41236C-page 10
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
TABLE 3-2:
PIC12F508/509 PINOUT DESCRIPTION
Name
GP0/ICSPDAT
GP1/ICSPCLK
GP2/T0CKI
GP3/MCLR/VPP
GP4/OSC2
GP5/OSC1/CLKIN
Function
Input
Type
Output
Type
GP0
TTL
CMOS Bidirectional I/O pin. Can be software programmed for internal
weak pull-up and wake-up from Sleep on pin change.
ICSPDAT
ST
CMOS In-Circuit Serial Programming™ data pin.
GP1
TTL
CMOS Bidirectional I/O pin. Can be software programmed for internal
weak pull-up and wake-up from Sleep on pin change.
ICSPCLK
ST
CMOS In-Circuit Serial Programming clock pin.
CMOS Bidirectional I/O pin.
Description
GP2
TTL
T0CKI
ST
—
Clock input to TMR0.
GP3
TTL
—
Input pin. Can be software programmed for internal weak
pull-up and wake-up from Sleep on pin change.
MCLR
ST
—
Master Clear (Reset). When configured as MCLR, this pin is
an active-low Reset to the device. Voltage on MCLR/VPP must
not exceed VDD during normal device operation or the device
will enter Programming mode. Weak pull-up always on if
configured as MCLR.
—
Programming voltage input.
VPP
HV
GP4
TTL
OSC2
—
CMOS Bidirectional I/O pin.
XTAL
GP5
TTL
OSC1
XTAL
—
Oscillator crystal output. Connections to crystal or resonator in
Crystal Oscillator mode (XT and LP modes only, GPIO in other
modes).
CMOS Bidirectional I/O pin.
Oscillator crystal input.
CLKIN
ST
—
External clock source input.
VDD
VDD
—
P
Positive supply for logic and I/O pins.
VSS
VSS
—
P
Ground reference for logic and I/O pins.
Legend: I = Input, O = Output, I/O = Input/Output, P = Power, — = Not used, TTL = TTL input,
ST = Schmitt Trigger input, HV = High Voltage
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 11
PIC12F508/509/16F505
FIGURE 3-2:
PIC16F505 BLOCK DIAGRAM
12
Flash
1K x 12
Program
Memory
8
Data Bus
Program Counter
RB0/ICSPCLK
RB1/ICSPDAT
RB2
RB3/MCLR/VPP
RB4/OSC2/CLKOUT
RB5/OSC1/CLKIN
RAM
72 bytes
File
Registers
Stack 1
Stack 2
Program 12
Bus
RAM Addr
9
PORTC
Addr MUX
Instruction Reg
Direct Addr
5
5-7
Indirect
Addr
FSR Reg
Status Reg
8
3
Device Reset
Timer
Instruction
Decode &
Control
OSC1/CLKIN
OSC2/CLKOUT
Timing
Generation
PORTB
Power-on
Reset
RC0
RC1
RC2
RC3
RC4
RC5/T0CKI
MUX
ALU
8
Watchdog
Timer
W Reg
Internal RC
OSC
Timer0
MCLR
VDD, VSS
DS41236C-page 12
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
TABLE 3-3:
PIC16F505 PINOUT DESCRIPTION
Name
RB0/ICSPDAT
RB1/ICSPCLK
Function
Input
Type
Output
Type
RB0
TTL
CMOS Bidirectional I/O pin. Can be software programmed for internal
weak pull-up and wake-up from Sleep on pin change.
ICSPDAT
ST
CMOS In-Circuit Serial Programming™ data pin.
RB1
TTL
CMOS Bidirectional I/O pin. Can be software programmed for internal
weak pull-up and wake-up from Sleep on pin change.
ICSPCLK
ST
CMOS In-Circuit Serial Programming clock pin.
CMOS Bidirectional I/O pin.
Description
RB2
RB2
TTL
RB3/MCLR/VPP
RB3
TTL
—
Input port. Can be software programmed for internal weak
pull-up and wake-up from Sleep on pin change.
MCLR
ST
—
Master Clear (Reset). When configured as MCLR, this pin is
an active-low Reset to the device. Voltage on MCLR/VPP must
not exceed VDD during normal device operation or the device
will enter Programming mode. Weak pull-up always on if
configured as MCLR.
VPP
HV
—
Programming voltage input.
RB4
TTL
OSC2
—
XTAL
CLKOUT
—
CMOS In EXTRC and INTRC modes, the pin output can be
configured for CLKOUT, which has 1/4 the frequency of OSC1
and denotes the instruction cycle rate.
RB5
TTL
RB4/OSC2/CLKOUT
RB5/OSC1/CLKIN
CMOS Bidirectional I/O pin. Can be software programmed for internal
weak pull-up and wake-up from Sleep on pin change.
Oscillator crystal output. Connections to crystal or resonator in
Crystal Oscillator mode (XT, HS and LP modes only).
CMOS Bidirectional I/O pin.
OSC1
XTAL
—
Crystal input.
CLKIN
ST
—
External clock source input.
RC0
RC0
TTL
CMOS Bidirectional I/O pin.
RC1
RC1
TTL
CMOS Bidirectional I/O pin.
RC2
RC2
TTL
CMOS Bidirectional I/O pin.
RC3
RC3
TTL
CMOS Bidirectional I/O pin.
RC4
RC4
TTL
CMOS Bidirectional I/O pin.
RC5/T0CKI
RC5
TTL
CMOS Bidirectional I/O pin.
T0CKI
ST
—
Clock input to TMR0.
VDD
VDD
—
P
Positive supply for logic and I/O pins.
VSS
VSS
—
P
Ground reference for logic and I/O pins.
Legend: I = Input, O = Output, I/O = Input/Output, P = Power, — = Not used, TTL = TTL input,
ST = Schmitt Trigger input, HV = High Voltage
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 13
PIC12F508/509/16F505
3.1
Clocking Scheme/Instruction
Cycle
3.2
Instruction Flow/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 take another instruction
cycle. However, due to the pipelining, each instruction
effectively executes in one cycle. If an instruction
causes the PC to change (e.g., GOTO), then two cycles
are required to complete the instruction (Example 3-1).
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 PC
is incremented every Q1 and the instruction is fetched
from program memory and latched into the 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 3-3 and Example 3-1.
A fetch cycle begins with the 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 3-3:
CLOCK/INSTRUCTION CYCLE
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
OSC1
Q1
Q2
Internal
phase
clock
Q3
Q4
PC
PC
PC + 1
Fetch INST (PC)
Execute INST (PC – 1)
EXAMPLE 3-1:
PC + 2
Fetch INST (PC + 1)
Execute INST (PC)
Fetch INST (PC + 2)
Execute INST (PC + 1)
INSTRUCTION PIPELINE FLOW
1. MOVLW 03H
2. MOVWF PORTB
3. CALL
SUB_1
4. BSF
PORTB, BIT1
Fetch 1
Execute 1
Fetch 2
Execute 2
Fetch 3
Execute 3
Fetch 4
Flush
Fetch SUB_1 Execute SUB_1
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.
DS41236C-page 14
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
4.0
MEMORY ORGANIZATION
FIGURE 4-1:
The PIC12F508/509/16F505 memories are 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 PIC12F509 and
PIC16F505, with data memory register files of more
than 32 registers, a banking scheme is used. Data
memory banks are accessed using the File Select
Register (FSR).
PROGRAM MEMORY MAP
AND STACK FOR THE
PIC12F508/509
PC<11:0>
12
CALL, RETLW
Stack Level 1
Stack Level 2
Reset Vector(1)
Program Memory Organization for
the PIC12F508/509
The PIC12F508 device has a 10-bit Program Counter
(PC) and PIC12F509 has a 11-bit Program Counter
(PC) capable of addressing a 2K x 12 program memory
space.
Only the first 512 x 12 (0000h-01FFh) for the
PIC12F508, and 1K x 12 (0000h-03FFh) for the
PIC12F509 are physically implemented (see
Figure 4-1). Accessing a location above these
boundaries will cause a wraparound within the first
512 x 12 space (PIC12F508) or 1K x 12 space
(PIC12F509). The effective Reset vector is a 0000h
(see Figure 4-1). Location 01FFh (PIC12F508) and
location 03FFh (PIC12F509) contain the internal
clock oscillator calibration value. This value should
never be overwritten.
On-chip Program
Memory
User Memory
Space
4.1
Preliminary
512 Word
01FFh
0200h
On-chip Program
Memory
1024 Word
03FFh
0400h
7FFh
Note 1:
© 2007 Microchip Technology Inc.
0000h
Address 0000h becomes the
effective Reset vector. Location
01FFh, 03FFh (PIC12F508,
PIC12F509) contains the MOVLW XX
internal oscillator calibration value.
DS41236C-page 15
PIC12F508/509/16F505
4.2
Program Memory Organization
For The PIC16F505
4.3
The PIC16F505 device has a 11-bit Program Counter
(PC) capable of addressing a 2K x 12 program memory
space.
The 1K x 12 (0000h-03FFh) for the PIC16F505 are
physically implemented. Refer to Figure 4-2. Accessing a location above this boundary will cause a wraparound within the first 1K x 12 space. The effective
Reset vector is at 0000h (see Figure 4-2). Location
03FFh contains the internal oscillator calibration value.
This value should never be overwritten.
FIGURE 4-2:
PROGRAM MEMORY MAP
AND STACK FOR THE
PIC16F505
PC<11:0>
12
CALL, RETLW
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 (SFR)
and General Purpose Registers (GPR).
The Special Function Registers include the TMR0 register, the Program Counter (PCL), the STATUS register,
the I/O registers (ports) and the File Select Register
(FSR). In addition, Special Function 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 PIC12F508/509, the register file is composed of
7 Special Function Registers, 9 General Purpose
Registers and 16 or 32 General Purpose Registers
accessed by banking (see Figure 4-3 and Figure 4-4).
For the PIC16F505, the register file is composed of 8
Special Function Registers, 8 General Purpose
Registers and 64 General Purpose Registers accessed
by banking (Figure 4-5).
Stack Level 1
Stack Level 2
Reset Vector(1)
Data Memory Organization
0000h
4.3.1
GENERAL PURPOSE REGISTER
FILE
User Memory
Space
The General Purpose Register file is accessed, either
directly or indirectly, through the File Select Register
(FSR). See Section 4.9 “Indirect Data Addressing:
INDF and FSR Registers”.
01FFh
0200h
On-chip Program
Memory
1024 Words
03FFh
0400h
7FFh
Note 1:
Address 0000h becomes the
effective Reset vector. Location
03FFh contains the MOVLW XX
internal oscillator calibration value.
DS41236C-page 16
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
FIGURE 4-3:
PIC12F508 REGISTER
FILE MAP
FIGURE 4-4:
PIC12F509 REGISTER
FILE MAP
FSR<6:5>
File Address
00
01
File Address
00h
INDF(1)
01h
TMR0
02h
PCL
03h
STATUS
04h
FSR
05h
OSCCAL
06h
GPIO
07h
00h
INDF(1)
01h
TMR0
02h
PCL
03h
STATUS
04h
FSR
05h
OSCCAL
06h
GPIO
20h
Addresses map
back to
addresses
in Bank 0.
07h
General
Purpose
Registers
General
Purpose
Registers
2Fh
0Fh
10h
30h
General
Purpose
Registers
1Fh
1Fh
3Fh
Bank 0
Note 1:
Note 1:
Not a physical register. See Section 4.9
“Indirect Data Addressing: INDF and
FSR Registers”.
FIGURE 4-5:
General
Purpose
Registers
Bank 1
Not a physical register. See Section 4.9
“Indirect Data Addressing: INDF and FSR
Registers”.
PIC16F505 REGISTER FILE MAP
FSR<6:5>
00
File Address
00h
INDF(1)
01h
TMR0
02h
PCL
03h
STATUS
04h
FSR
05h
OSCCAL
06h
PORTB
07h
PORTC
08h
General
Purpose
Registers
0Fh
10h
01
20h
60h
2Fh
4Fh
6Fh
30h
50h
70h
General
Purpose
Registers
3Fh
Bank 0
Note 1:
40h
11
Addresses map back to
addresses in Bank 0.
General
Purpose
Registers
1Fh
10
General
Purpose
Registers
5Fh
Bank 1
General
Purpose
Registers
7Fh
Bank 2
Bank 3
Not a physical register. See Section 4.9 “Indirect Data Addressing: INDF and FSR Registers”.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 17
PIC12F508/509/16F505
4.3.2
SPECIAL FUNCTION REGISTERS
The Special Function Registers (SFRs) are registers
used by the CPU and peripheral functions to control the
operation of the device (Table 4-1).
The Special Function Registers can be classified into
two sets. The Special Function Registers associated
with the “core” functions are described in this section.
Those related to the operation of the peripheral
features are described in the section for each
peripheral feature.
TABLE 4-1:
Address
SPECIAL FUNCTION REGISTER (SFR) SUMMARY (PIC12F508/509)
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
Power-On
Reset(2)
Page #
00h
INDF
Uses Contents of FSR to Address Data Memory (not a physical
register)
xxxx xxxx
26
01h
TMR0
8-bit Real-Time Clock/Counter
xxxx xxxx
33
02h(1)
PCL
Low-order 8 bits of PC
1111 1111
25
03h
STATUS
GPWU
F
04h
—
PA0(5)
TO
PD
FSR
Indirect Data Memory Address Pointer
04h(4)
FSR
Indirect Data Memory Address Pointer
05h
OSCCAL
CAL6
CAL5
06h
GPIO
—
—
N/A
TRISGPIO
—
—
N/A
OPTION
Z
DC
C
0-01
1xxx(3)
20
111x xxxx
26
110x xxxx
26
CAL4
CAL3
CAL2
CAL1
CAL0
—
1111 111-
24
GP5
GP4
GP3
GP2
GP1
GP0
--xx xxxx
29
--11 1111
29
1111 1111
22
I/O Control Register
GPWU GPPU TOCS TOSE
PSA
PS2
PS1
PS0
Legend: – = unimplemented, read as ‘0’, x = unknown, u = unchanged, q = value depends on condition.
Note 1: The upper byte of the Program Counter is not directly accessible. See Section 4.7 “Program Counter”
for an explanation of how to access these bits.
2: Other (non Power-up) Resets include external Reset through MCLR, Watchdog Timer and wake-up on pin
change Reset.
3: If Reset was due to wake-up on pin change, then bit 7 = 1. All other Resets will cause bit 7 = 0.
4: PIC12F509 only.
5: This bit is used on the PIC12F509. For code compatibility do not use this bit on the PIC12F508.
DS41236C-page 18
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
TABLE 4-2:
Address
SPECIAL FUNCTION REGISTER (SFR) SUMMARY (PIC16F505)
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1 Bit 0
Value on
Power-On
Reset(2)
Page #
00h
INDF
Uses Contents of FSR to Address Data Memory (not a physical
register)
xxxx xxxx
26
01h
TMR0
8-bit Real-Time Clock/Counter
xxxx xxxx
33
02h
PCL
Low-order 8 bits of PC
1111 1111
25
03h
STATUS
RBWUF
0-01 1xxx
20
Indirect Data Memory Address Pointer
(1)
04h
FSR
05h
OSCCAL
06h
07h
—
PA0
CAL4
TO
Z
DC
C
110x xxxx
26
CAL2
CAL1
CAL0
—
1111 111-
24
CAL6
CAL5
PORTB
—
—
RB5
RB4
RB3
RB2
RB1
RB0
--xx xxxx
29
PORTC
—
—
RC5
RC4
RC3
RC2
RC1
RC0
--xx xxxx
29
N/A
TRISB
—
—
I/O Control Register
--11 1111
29
N/A
TRISC
—
—
I/O Control Register
--11 1111
29
N/A
OPTION
RBWU
RBPU
1111 1111
23
TOCS
CAL3
PD
TOSE
PSA
PS2
PS1
PS0
Legend: – = unimplemented, read as ‘0’, x = unknown, u = unchanged, q = value depends on condition.
Note 1: If Reset was due to wake-up on pin change, then bit 7 = 1. All other Resets will cause bit 7 = 0.
2: Other (non Power-up) Resets include external reset through MCLR, Watchdog Timer and wake-up on pin
change Reset.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 19
PIC12F508/509/16F505
4.4
STATUS Register
This register contains the arithmetic status of the ALU,
the Reset status and the page preselect bit.
The STATUS register can be the destination for any
instruction, as with any other register. If the STATUS
register is the destination for an instruction that affects
the Z, DC or C bits, then the write to these three bits is
disabled. These bits are set or cleared according to the
device logic. Furthermore, the TO and PD bits are not
writable. Therefore, the result of an instruction with the
STATUS register as destination may be different than
intended.
REGISTER 4-1:
For example, CLRF STATUS, will clear the upper three
bits and set the Z bit. This leaves the STATUS register
as 000u u1uu (where u = unchanged).
Therefore, it is recommended that only BCF, BSF and
MOVWF instructions be used to alter the STATUS register. These instructions do not affect the Z, DC or C bits
from the STATUS register. For other instructions which
do affect Status bits, see Section 8.0 “Instruction Set
Summary”.
STATUS REGISTER (ADDRESS: 03h) (PIC12F508/509)
R/W-0
R/W-0
R/W-0
R-1
R-1
R/W-x
R/W-x
R/W-x
GPWUF
—
PA0
TO
PD
Z
DC
C
bit 7
bit 0
bit 7
GPWUF: GPIO Reset bit
1 = Reset due to wake-up from Sleep on pin change
0 = After power-up or other Reset
bit 6
Reserved: Do not use
bit 5
PA0: Program Page Preselect bits(1)
1 = Page 1 (200h-3FFh)
0 = Page 0 (000h-1FFh)
Each page is 512 bytes.
Using the PA0 bit as a general purpose read/write bit in devices which do not use it for program page
preselect is not recommended, since this may affect upward compatibility with future products.
bit 4
TO: Time-out bit
1 = After power-up, CLRWDT instruction, or SLEEP instruction
0 = A WDT time-out occurred
bit 3
PD: Power-down bit
1 = After power-up or by the CLRWDT instruction
0 = By execution of the SLEEP instruction
bit 2
Z: Zero bit
1 = The result of an arithmetic or logic operation is zero
0 = The result of an arithmetic or logic operation is not zero
bit 1
DC: Digit carry/borrow bit (for ADDWF and SUBWF instructions)
ADDWF:
1 = A carry from the 4th low-order bit of the result occurred
0 = A carry from the 4th low-order bit of the result did not occur
SUBWF:
1 = A borrow from the 4th low-order bit of the result did not occur
0 = A borrow from the 4th low-order bit of the result occurred
bit 0
C: Carry/borrow bit (for ADDWF, SUBWF and RRF, RLF instructions)
ADDWF:
SUBWF:
RRF or RLF:
1 = A carry occurred
1 = A borrow did not occur
Load bit with LSb or MSb, respectively
0 = A carry did not occur
0 = A borrow occurred
Note 1:
This bit is used on the PIC12F509. For code compatibility do not use this bit on the
PIC12F508.
Legend:
DS41236C-page 20
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
Preliminary
x = Bit is unknown
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
REGISTER 4-2:
STATUS REGISTER (ADDRESS: 03h) (PIC16F505)
R/W-0
R/W-0
R/W-0
R-1
R-1
R/W-x
R/W-x
R/W-x
RBWUF
—
PA0
TO
PD
Z
DC
C
bit 7
bit 0
bit 7
RBWUF: PORTB Reset bit
1 = Reset due to wake-up from Sleep on pin change
0 = After power-up or other Reset
bit 6
Reserved: Do not use
bit 5
PA0: Program Page Preselect bits
1 = Page 1 (200h-3FFh)
0 = Page 0 (000h-1FFh)
Each page is 512 bytes.
Using the PA0 bit as a general purpose read/write bit in devices which do not use it for program
page preselect is not recommended, since this may affect upward compatibility with future
products.
bit 4
TO: Time-out bit
1 = After power-up, CLRWDT instruction, or SLEEP instruction
0 = A WDT time-out occurred
bit 3
PD: Power-down bit
1 = After power-up or by the CLRWDT instruction
0 = By execution of the SLEEP instruction
bit 2
Z: Zero bit
1 = The result of an arithmetic or logic operation is zero
0 = The result of an arithmetic or logic operation is not zero
bit 1
DC: Digit carry/borrow bit (for ADDWF and SUBWF instructions)
ADDWF:
1 = A carry from the 4th low-order bit of the result occurred
0 = A carry from the 4th low-order bit of the result did not occur
SUBWF:
1 = A borrow from the 4th low-order bit of the result did not occur
0 = A borrow from the 4th low-order bit of the result occurred
bit 0
C: Carry/borrow bit (for ADDWF, SUBWF and RRF, RLF instructions)
ADDWF:
SUBWF:
RRF or RLF:
1 = A carry occurred
1 = A borrow did not occur Load bit with LSb or MSb, respectively
0 = A carry did not occur 0 = A borrow occurred
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
© 2007 Microchip Technology Inc.
Preliminary
x = Bit is unknown
DS41236C-page 21
PIC12F508/509/16F505
4.5
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.
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/RBPU and
GPWU/RBWU).
Note:
If the T0CS bit is set to ‘1’, it will override
the TRIS function on the T0CKI pin.
By executing the OPTION instruction, the contents of
the W register will be transferred to the OPTION register. A Reset sets the OPTION<7:0> bits.
REGISTER 4-3:
OPTION REGISTER (PIC12F508/509)
W-1
W-1
W-1
W-1
W-1
W-1
W-1
W-1
GPWU
GPPU
T0CS
T0SE
PSA
PS2
PS1
PS0
bit 7
bit 0
bit 7
GPWU: Enable Wake-up on Pin Change bit (GP0, GP1, GP3)
1 = Disabled
0 = Enabled
bit 6
GPPU: Enable Weak Pull-ups bit (GP0, GP1, GP3)
1 = Disabled
0 = Enabled
bit 5
T0CS: Timer0 Clock Source Select bit
1 = Transition on T0CKI pin (overrides TRIS on the T0CKI pin)
0 = Transition on internal instruction cycle clock, FOSC/4
bit 4
T0SE: Timer0 Source Edge Select bit
1 = Increment on high-to-low transition on the T0CKI pin
0 = Increment on low-to-high transition on the T0CKI pin
bit 3
PSA: Prescaler Assignment bit
1 = Prescaler assigned to the WDT
0 = Prescaler assigned to Timer0
bit 2-0
PS<2:0>: Prescaler Rate Select bits
Bit Value
000
001
010
011
100
101
110
111
Timer0 Rate WDT Rate
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
Legend:
DS41236C-page 22
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
Preliminary
x = Bit is unknown
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
REGISTER 4-4:
OPTION REGISTER (PIC16F505)
W-1
W-1
W-1
W-1
W-1
W-1
W-1
W-1
RBWU
RBPU
T0CS
T0SE
PSA
PS2
PS1
PS0
bit 7
bit 0
bit 7
RBWU: Enable Wake-up on Pin Change bit (RB0, RB1, RB3, RB4)
1 = Disabled
0 = Enabled
bit 6
RBPU: Enable Weak Pull-ups bit (RB0, RB1, RB3, RB4)
1 = Disabled
0 = Enabled
bit 5
T0CS: Timer0 clock Source Select bit
1 = Transition on T0CKI pin (overrides TRIS on the T0CKI pin)
0 = Transition on internal instruction cycle clock, FOSC/4
bit 4
T0SE: Timer0 Source Edge Select bit
1 = Increment on high-to-low transition on the T0CKI pin
0 = Increment on low-to-high transition on the T0CKI pin
bit 3
PSA: Prescaler Assignment bit
1 = Prescaler assigned to the WDT
0 = Prescaler assigned to Timer0
bit 2-0
PS<2:0>: Prescaler Rate Select bits
Bit Value
000
001
010
011
100
101
110
111
Timer0 Rate WDT Rate
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
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
© 2007 Microchip Technology Inc.
Preliminary
x = Bit is unknown
DS41236C-page 23
PIC12F508/509/16F505
4.6
OSCCAL Register
The Oscillator Calibration (OSCCAL) register is used to
calibrate the internal precision 4 MHz oscillator. It
contains seven bits for calibration.
Note:
Erasing the device will also erase the preprogrammed 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.
After you move in the calibration constant, do not
change the value. See Section 7.2.5 “Internal 4 MHz
RC Oscillator”.
REGISTER 4-5:
OSCCAL REGISTER (ADDRESS: 05h)
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-1
R/W-0
CAL6
CAL5
CAL4
CAL3
CAL2
CAL1
CAL0
—
bit 7
bit 0
bit 7-1
CAL<6:0>: Oscillator Calibration bits
0111111 = Maximum frequency
•
•
•
0000001
0000000 = Center frequency
1111111
•
•
•
1000000 = Minimum frequency
bit 0
Unimplemented: Read as ‘0’
Legend:
DS41236C-page 24
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = Bit is set
‘0’ = Bit is cleared
Preliminary
x = Bit is unknown
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
4.7
4.7.1
Program Counter
EFFECTS OF RESET
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.
The PC 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.
For a GOTO instruction, bits 8:0 of the PC are provided
by the GOTO instruction word. The Program Counter
(PCL) is mapped to PC<7:0>. Bit 5 of the STATUS
register provides page information to bit 9 of the PC
(Figure 4-6).
The STATUS register page preselect bits are cleared
upon a Reset, which means that page 0 is pre-selected.
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 4-6).
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 4-6:
LOADING OF PC
BRANCH INSTRUCTIONS
GOTO Instruction
11 10 9 8 7
PC
0
PCL
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.
4.8
The PIC12F508/509/16F505 devices have a 2-deep,
12-bit wide hardware PUSH/POP stack.
A CALL instruction will PUSH the current value of Stack 1
into Stack 2 and then PUSH the current PC value, incremented by one, into Stack Level 1. If more than two
sequential CALLs are executed, only the most recent two
return addresses are stored.
A RETLW instruction will POP the contents of Stack
Level 1 into the PC and then copy Stack Level 2
contents into Stack Level 1. If more than two sequential
RETLWs are executed, the stack will be filled with the
address previously stored in Stack 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.
Note 1: There are no Status bits to indicate stack
overflows or stack underflow conditions.
2: There are no instruction mnemonics
called PUSH or POP. These are actions
that occur from the execution of the CALL
and RETLW instructions.
Instruction Word
7
Stack
PA0
0
Status
CALL or Modify PCL Instruction
11 10 9 8 7
PC
0
PCL
7
Instruction Word
Reset to ‘0’
PA0
0
Status
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 25
PIC12F508/509/16F505
4.9
EXAMPLE 4-1:
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.
4.9.1
NEXT
MOVLW
MOVWF
CLRF
INCF
BTFSC
GOTO
CONTINUE
:
:
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.
HOW TO CLEAR RAM
USING INDIRECT
ADDRESSING
0x10
FSR
INDF
;initialize pointer
;to RAM
;clear INDF
;register
;inc pointer
;all done?
;NO, clear next
FSR,F
FSR,4
NEXT
;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.
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 4-1.
The FSR<4:0> bits are used to select data memory
addresses 00h to 1Fh.
PIC12F508 – Does not use banking. FSR <7:5> are
unimplemented and read as ‘1’s.
PIC12F509 – Uses FSR<5>. Selects between bank 0
and bank 1. FSR<7:6> is unimplemented, read as ‘1’.
PIC16F505 – Uses FSR<6:5>. Selects from bank 0 to
bank 3. FSR<7> is unimplemented, read as ‘1’.
FIGURE 4-7:
DIRECT/INDIRECT ADDRESSING (PIC12F508/509)
Direct Addressing
(FSR)
6 5
Bank Select
4
Indirect Addressing
(opcode)
0
6
Location Select
5
4
Bank
00
(FSR)
0
Location Select
01
00h
Addresses
map back to
addresses
in Bank 0.
Data
Memory(1)
0Fh
10h
1Fh
Bank 0
Note 1:
2:
3Fh
Bank 1(2)
For register map detail, see Section 4.3 “Data Memory Organization”.
PIC12F509.
DS41236C-page 26
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
FIGURE 4-8:
DIRECT/INDIRECT ADDRESSING (PIC16F505)
Direct Addressing
(FSR)
6 5
Bank Select
4
Indirect Addressing
(opcode)
0
6
Location Select
01
10
00h
(FSR)
0
Location Select
11
Addresses
map back to
addresses
in Bank 0.
0Fh
10h
1Fh
Bank 0
Note 1:
4
Bank
00
Data
Memory(1)
5
3Fh
Bank 1
5Fh
Bank 2
7Fh
Bank 3
For register map detail, see Section 4.3 “Data Memory Organization”.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 27
PIC12F508/509/16F505
NOTES:
DS41236C-page 28
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
5.0
I/O PORT
5.4
As with any other register, the I/O register(s) can be
written and read under program control. However, read
instructions (e.g., MOVF PORTB,W) always read the I/O
pins independent of the pin’s Input/Output modes. On
Reset, all I/O ports are defined as input (inputs are at
high-impedance) since the I/O control registers are all
set.
Note:
5.1
On the PIC12F508/509, I/O PORTB is referenced as GPIO. On the PIC16F505, I/O
PORTB is referenced as PORTB.
The equivalent circuit for an I/O port pin is shown in
Figure 5-2. All port pins, except RB3/GP3 which is
input only, may be used for both input and output operations. For input operations, these ports are non-latching. Any input must be present until read by an input
instruction (e.g., MOVF PORTB, 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 RB3/GP3) can be
programmed individually as input or output.
FIGURE 5-1:
PORTB/GPIO
PORTB/GPIO is an 8-bit I/O register. Only the loworder 6 bits are used (RB/GP<5:0>). Bits 7 and 6 are
unimplemented and read as ‘0’s. Please note that RB3/
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 a port
read. Pins RB0/GP0, RB1/GP1, RB3/GP3 and RB4
can be configured with weak pull-ups and also for
wake-up on change. The wake-up on change and weak
pull-up functions are not pin selectable. If RB3/GP3/
MCLR is configured as MCLR, weak pull-up is always
on and wake-up on change for this pin is not enabled.
5.2
I/O Interfacing
PORTC (PIC16F505 Only)
Data
Bus
D
WR
Port
W
Reg
CK
VDD VDD
Q
P
N
D
TRIS ‘f’
I/O
pin
Q
TRIS
Latch
CK
VSS
VSS
Q
Reset
(1)
TRIS Registers
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 High-Impedance mode. A
‘0’ puts the contents of the output data latch on the
selected pins, enabling the output buffer. The exceptions are RB3/GP3, which is input only and the T0CKI
pin, which may be controlled by the OPTION register.
See Register 4-3 and Register 4-4.
Note:
Q
Data
Latch
PORTC is an 8-bit I/O register. Only the low-order 6 bits
are used (RC<5:0>). Bits 7 and 6 are unimplemented
and read as ‘0’s.
5.3
PIC12F508/509/16F505
EQUIVALENT CIRCUIT
FOR A SINGLE I/O PIN
RD Port
Note 1:
See Table 3-3 for buffer type.
A read of the ports reads the pins, not the
output data latches. That is, if an output
driver on a pin is enabled and driven high,
but the external system is holding it low, a
read of the port will indicate that the pin is
low.
The TRIS registers are “write-only” and are set (output
drivers disabled) upon Reset.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 29
PIC12F508/509/16F505
TABLE 5-1:
Address
SUMMARY OF PORT REGISTERS
Name
Bit 7
Bit 6
TRISGPIO(1)
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
Power-On
Reset
Value on
All Other
Resets
—
—
I/O Control Register
--11 1111
--11 1111
N/A
(2)
TRISB
—
—
I/O Control Register
--11 1111
--11 1111
N/A
TRISC(2)
—
—
I/O Control Register
--11 1111
--11 1111
N/A
OPTION(1)
GPWU
GPPU
TOCS
TOSE
PSA
PS2
PS1
PS0
1111 1111
1111 1111
N/A
OPTION(2)
RBWU
RBPU
TOCS
TOSE
PSA
PS2
PS1
PS0
1111 1111
1111 1111
03h
STATUS
(1)
GPWUF
—
PAO
TO
PD
Z
DC
C
0-01 1xxx
q00q quuu(3)
03h
STATUS(2)
RBWUF
—
PAO
TO
PD
Z
DC
C
0-01 1xxx
q00q quuu(3)
N/A
(1)
06h
GPIO
—
—
GP5
GP4
GP3
GP2
GP1
GP0
--xx xxxx
--uu uuuu
06h
PORTB(2)
—
—
RB5
RB4
RB3
RB2
RB1
RB0
--xx xxxx
--uu uuuu
07h
PORTC(2)
—
—
RC5
RC4
RC3
RC2
RC1
RC0
--xx xxxx
--uu uuuu
Legend:
Note 1:
2:
3:
Shaded cells are not used by Port registers, read as ‘0’. – = unimplemented, read as ‘0’, x = unknown, u = unchanged,
q = depends on condition.
PIC12F508/509 only.
PIC16F505 only.
If Reset was due to wake-up on pin change, then bit 7 = 1. All other Resets will cause bit 7 = 0.
DS41236C-page 30
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
5.5
I/O Programming Considerations
5.5.1
BIDIRECTIONAL 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 bit 5 of PORTB/GPIO will
cause all eight bits of PORTB/GPIO to be read into the
CPU, bit 5 to be set and the PORTB/GPIO value to be
written to the output latches. If another bit of PORTB/
GPIO is used as a bidirectional I/O pin (say bit 0) 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 bit 0 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
Read-Modify-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.
FIGURE 5-2:
READ-MODIFY-WRITE
INSTRUCTIONS ON AN
I/O PORT(e.g. PIC16F505)
;Initial PORTB Settings
;PORTB<5:3> Inputs
;PORTB<2:0> Outputs
;
;
PORTB latch PORTB pins
;
------------------BCF
PORTB, 5 ;--01 -ppp
--11 pppp
BCF
PORTB, 4 ;--10 -ppp
--11 pppp
MOVLW 007h;
TRIS
PORTB
;--10 -ppp
--11 pppp
;
Note 1: The user may have expected the pin values to
be ‘--00 pppp’. The 2nd BCF caused RB5 to
be latched as the pin value (High).
5.5.2
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
causes that file to be read into the CPU. 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.
SUCCESSIVE I/O OPERATION (PIC16F505 Shown)
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
PC
Instruction
Fetched
EXAMPLE 5-1:
MOVWF PORTB
PC + 1
MOVF PORTB, W
Q1 Q2 Q3 Q4
PC + 2
PC + 3
This example shows a write to PORTB
followed by a read from PORTB.
NOP
NOP
Data setup time = (0.25 TCY – TPD)
where: TCY = instruction cycle.
RB<5:0>
TPD = propagation delay
Port pin
written here
Instruction
Executed
MOVWF PORTB
(Write to PORTB)
© 2007 Microchip Technology Inc.
Port pin
sampled here
MOVF PORTB,W
(Read PORTB)
Therefore, at higher clock frequencies, a
write followed by a read may be problematic.
NOP
Preliminary
DS41236C-page 31
PIC12F508/509/16F505
NOTES:
DS41236C-page 32
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
6.0
TIMER0 MODULE AND TMR0
REGISTER
Counter mode is selected by setting the T0CS bit
(OPTION<5>). In this mode, Timer0 will increment
either on every rising or falling edge of pin T0CKI. The
T0SE bit (OPTION<4>) determines the source edge.
Clearing the T0SE bit selects the rising edge. Restrictions on the external clock input are discussed in detail
in Section 6.1 “Using Timer0 with an External
Clock”.
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 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:
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 values of 1:2, 1:4,...,
1:256 are selectable. Section 6.2 “Prescaler” details
the operation of the prescaler.
A summary of registers associated with the Timer0
module is found in Table 6-1.
TIMER0 BLOCK DIAGRAM
Data Bus
(GP2/RC5)/T0CKI FOSC/4
Pin
0
PSOUT
1
1
Programmable
Prescaler(2)
0
T0SE
8
Sync with
Internal
Clocks
TMR0 Reg
PSOUT
(2 TCY delay) Sync
3
T0CS(1)
Note 1:
2:
The prescaler is shared with the Watchdog Timer (Figure 6-5).
TIMER0 TIMING: INTERNAL CLOCK/NO PRESCALE
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
PC – 1
Instruction
Fetch
Timer0
PSA(1)
Bits T0CS, T0SE, PSA, PS2, PS1 and PS0 are located in the OPTION register.
FIGURE 6-2:
PC
(Program
Counter)
PS2, PS1, PS0(1)
PC
MOVWF TMR0
T0
T0 + 1
Instruction
Executed
© 2007 Microchip Technology Inc.
PC + 1
PC + 2
PC + 3
PC + 4
PC + 5
PC + 6
MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W
T0 + 2
Write TMR0
executed
NT0 + 1
NT0
Read TMR0
reads NT0
Read TMR0
reads NT0
Preliminary
Read TMR0
reads NT0
NT0 + 2
Read TMR0
Read TMR0
reads NT0 + 1 reads NT0 + 2
DS41236C-page 33
PIC12F508/509/16F505
FIGURE 6-3:
PC
(Program
Counter)
TIMER0 TIMING: INTERNAL CLOCK/PRESCALE 1:2
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
PC – 1
Instruction
Fetch
PC
MOVWF TMR0
T0
Timer0
PC + 4
PC + 5
PC + 6
Read TMR0
reads NT0
Read TMR0
reads NT0
NT0 + 1
Read TMR0
Read TMR0
reads NT0 + 1 reads NT0 + 2
Read TMR0
reads NT0
REGISTERS ASSOCIATED WITH TIMER0
Name
TMR0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
OPTION
GPWU
GPPU
N/A
OPTION
(2)
RBWU
RBPU
N/A
TRISGPIO(1), (3)
—
—
—
—
(2), (3)
T0CS
T0SE
PSA
PS2
PS1
PS0
T0CS
T0SE
PSA
PS2
PS1
PS0
I/O Control Register
RC4
RC3
RC1
xxxx xxxx
uuuu uuuu
1111 1111
1111 1111
RC0
1111 1111
1111 1111
--11 1111
--11 1111
--11 1111
--11 1111
TRISC
Legend:
Note 1:
2:
3:
Shaded cells are not used by Timer0. – = unimplemented, x = unknown, u = unchanged.
PIC12F508/509 only.
PIC16F505 only.
The TRIS of the T0CKI pin is overridden when T0CS = 1.
Preliminary
RC2
Value on
All Other
Resets
N/A
DS41236C-page 34
RC5
Value on
Power-On
Reset
Bit 0
Timer0 – 8-bit Real-Time Clock/Counter
(1)
N/A
PC + 3
NT0
Write TMR0
executed
TABLE 6-1:
01h
PC + 2
T0 + 1
Instruction
Executed
Address
PC + 1
MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W MOVF TMR0,W
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
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 (TOSC) 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 2 TOSC (and a small RC delay of 2 Tt0H) and low
for at least 2 TOSC (and a small RC delay of 2 Tt0H).
Refer to the electrical specification of the desired
device.
FIGURE 6-4:
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 4 TOSC (and a small RC delay of 4 Tt0H) 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 Tt0H. 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.
TIMER0 TIMING WITH EXTERNAL CLOCK
Q1 Q2 Q3 Q4
Q1 Q2 Q3 Q4
Q1 Q2 Q3 Q4
External Clock Input or
Prescaler Output (2)
Q1 Q2 Q3 Q4
Small pulse
misses sampling
(1)
External Clock/Prescaler
Output After Sampling
(3)
Increment Timer0 (Q4)
Timer0
Note 1:
T0
T0 + 1
T0 + 2
Delay from clock input change to Timer0 increment is 3 TOSC to 7 TOSC. (Duration of Q = TOSC). Therefore, the error
in measuring the interval between two edges on Timer0 input = ±4 TOSC max.
2:
External clock if no prescaler selected; prescaler output otherwise.
3:
The arrows indicate the points in time where sampling occurs.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 35
PIC12F508/509/16F505
6.2
EXAMPLE 6-1:
Prescaler
An 8-bit counter is available as a prescaler for the
Timer0 module or as a postscaler for the Watchdog
Timer (WDT), respectively (see Section 7.6 “Watchdog Timer (WDT)”). For simplicity, this counter is
being referred to as “prescaler” throughout this data
sheet.
Note:
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 PS<2:0> 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
CHANGING PRESCALER
(TIMER0 → WDT)
CLRWDT
;Clear WDT
CLRF
TMR0
;Clear TMR0 & Prescaler
MOVLW ‘00xx1111’b ;These 3 lines (5, 6, 7)
OPTION
;are required only if
;desired
CLRWDT
;PS<2:0> are 000 or 001
MOVLW ‘00xx1xxx’b ;Set Postscaler to
OPTION
;desired WDT rate
To change the prescaler from the WDT to the Timer0
module, use the sequence shown in Example 6-2. This
sequence must be used even if the WDT is disabled. A
CLRWDT instruction should be executed before
switching the prescaler.
EXAMPLE 6-2:
CLRWDT
MOVLW
‘xxxx0xxx’
CHANGING PRESCALER
(WDT → TIMER0)
;Clear WDT and
;prescaler
;Select TMR0, new
;prescale value and
;clock source
OPTION
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.
DS41236C-page 36
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
BLOCK DIAGRAM OF THE TIMER0/WDT PRESCALER(1), (2)
FIGURE 6-5:
TCY (= FOSC/4)
Data Bus
0
(GP2/RC5)/T0CKI
pin
1
8
M
U
X
1
M
U
X
0
T0SE
T0CS
0
Watchdog
Timer
1
M
U
X
Sync
2
Cycles
TMR0 Reg
PSA
8-bit Prescaler
8
8-to-1 MUX
PS<2:0>
PSA
WDT Enable bit
1
0
MUX
PSA
WDT
Time-out
Note 1:
2:
T0CS, T0SE, PSA, PS<2:0> are bits in the OPTION register.
T0CKI is shared with pin RC5 on the PIC16F505 and pin GP2 on the PIC12F508/509.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 37
PIC12F508/509/16F505
NOTES:
DS41236C-page 38
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
7.0
SPECIAL FEATURES OF THE
CPU
The PIC12F508/509/16F505 devices have a Watchdog
Timer, which can be shut off only through configuration
bit WDTE. It runs off of its own RC oscillator for added
reliability. If using HS (PIC16F505), 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 VDD power-up. With this timer
on-chip, most applications need no external Reset
circuitry.
What sets a microcontroller apart from other processors are special circuits that deal with the needs of realtime applications. The PIC12F508/509/16F505
microcontrollers have a host of such features intended
to maximize system reliability, minimize cost through
elimination of external components, provide powersaving operating modes and offer code protection.
These features are:
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.
• 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™
• Clock Out
REGISTER 7-1:
—
—
7.1
Configuration Bits
The PIC12F508/509/16F505 Configuration Words
consist of 12 bits. Configuration bits can be
programmed to select various device configurations.
Three bits are for the selection of the oscillator type;
(two bits on the PIC12F508/509), one bit is the
Watchdog Timer enable bit, one bit is the MCLR enable
bit and one bit is for code protection (Register 7-1,
Register 7-2).
CONFIGURATION WORD FOR PIC12F508/509(1)
—
—
—
—
—
MCLRE
CP
WDTE
FOSC1
bit 11
FOSC0
bit 0
bit 11-5
Unimplemented: Read as ‘0’
bit 4
MCLRE: GP3/MCLR Pin Function Select bit
1 = GP3/MCLR pin function is MCLR
0 = GP3/MCLR pin function is digital I/O, MCLR internally tied to VDD
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
FOSC<1:0>: Oscillator Selection bits
11 = EXTRC = external selection bits
10 = INTRC = internal RC oscillator
01 = XT oscillator
00 = LP oscillator
Note 1:
Refer to the “PIC12F508/509 Memory Programming Specifications” (DS41227) to determine how to access
the Configuration Word. The Configuration Word is not user addressable during device operation.
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = bit is set
‘0’ = bit is cleared
© 2007 Microchip Technology Inc.
Preliminary
x = bit is unknown
DS41236C-page 39
PIC12F508/509/16F505
REGISTER 7-2:
—
—
CONFIGURATION WORD FOR PIC16F505(1)
—
—
—
—
MCLRE
CP
WDTE
FOSC2
FOSC1
bit 11
FOSC0
bit 0
bit 11-6
Unimplemented: Read as ‘0’
bit 5
MCLRE: RB3/MCLR Pin Function Select bit
1 = RB3/MCLR pin function is MCLR
0 = RB3/MCLR pin function is digital I/O, MCLR internally tied to VDD
bit 4
CP: Code Protection bit
1 = Code protection off
0 = Code protection on
bit 3
WDTE: Watchdog Timer Enable bit
1 = WDT enabled
0 = WDT disabled
bit 2-0
FOSC<1:0>: Oscillator Selection bits
111 = External RC oscillator/CLKOUT function on RB4/OSC2/CLKOUT pin
110 = External RC oscillator/RB4 function on RB4/OSC2/CLKOUT pin
101 = Internal RC oscillator/CLKOUT function on RB4/OSC2/CLKOUT pin
100 = Internal RC oscillator/RB4 function on RB4/OSC2/CLKOUT pin
011 = EC oscillator/RB4 function on RB4/OSC2/CLKOUT pin
010 = HS oscillator
001 = XT oscillator
000 = LP oscillator
Note 1: Refer to the “PIC16F505 Memory Programming Specifications” (DS41226) to determine how to
access the Configuration Word. The Configuration Word is not user addressable during device
operation.
Legend:
R = Readable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
-n = Value at POR
‘1’ = bit is set
‘0’ = bit is cleared
DS41236C-page 40
Preliminary
x = bit is unknown
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
7.2
7.2.1
FIGURE 7-1:
Oscillator Configurations
OSCILLATOR TYPES
The PIC12F508/509/16F505 devices can be operated
in up to six different oscillator modes. The user can
program up to three configuration bits (FOSC<1:0>
[PIC12F508/509], FOSC<2:0> [PIC16F505]). To select
one of these modes:
C1(1)
Sleep
Low-Power Crystal
Crystal/Resonator
High-Speed Crystal/Resonator
(PIC16F505 only)
• INTRC: Internal 4 MHz Oscillator
• EXTRC: External Resistor/Capacitor
• EC:
External High-Speed Clock Input
(PIC16F505 only)
XTAL
RS(2)
RF(3)
To internal
logic
OSC2
C2(1)
Note 1:
See Capacitor Selection tables for
recommended values of C1 and C2.
A series resistor (RS) may be required for AT
strip cut crystals.
RF approx. value = 10 MΩ.
2:
3:
CRYSTAL OSCILLATOR/CERAMIC
RESONATORS
In HS (PIC16F505), XT or LP modes, a crystal or
ceramic resonator is connected to the (GP5/RB5)/
OSC1/(CLKIN) and (GP4/RB4)/OSC2/(CLKOUT) pins
to establish oscillation (Figure 7-1). The PIC12F508/
509/16F505 oscillator designs require 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 HS (PIC16F505), XT or LP
modes, the device can have an external clock source
drive the (GP5/RB5)/OSC1/CLKIN pin (Figure 7-2).
Note 1: This device has been designed to perform to the parameters of its data sheet.
It has been tested to an electrical
specification designed to determine its
conformance with these parameters.
Due to process differences in the
manufacture of this device, this device
may have different performance characteristics than its earlier version. These
differences may cause this device to
perform differently in your application
than the earlier version of this device.
FIGURE 7-2:
EXTERNAL CLOCK INPUT
OPERATION (HS, XT OR
LP OSC
CONFIGURATION)
OSC1
Clock from
ext. system
PIC12F508/509
PIC16F505
Open
TABLE 7-1:
OSC2
CAPACITOR SELECTION FOR
CERAMIC RESONATORS –
PIC12F508/509/16F505(1)
Osc
Type
Resonator
Freq.
Cap. Range
C1
Cap. Range
C2
XT
4.0 MHz
30 pF
30 pF
16 MHz
10-47 pF
10-47 pF
(2)
HS
Note 1:
2: The user should verify that the device
oscillator starts and performs as
expected. Adjusting the loading capacitor
values and/or the Oscillator mode may
be required.
© 2007 Microchip Technology Inc.
PIC12F508/509
PIC16F505
OSC1
• LP:
• XT:
• HS:
7.2.2
CRYSTAL OPERATION
(OR CERAMIC
RESONATOR)
(HS, XT OR LP OSC
CONFIGURATION)
Preliminary
2:
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.
PIC16F505 only.
DS41236C-page 41
PIC12F508/509/16F505
TABLE 7-2:
CAPACITOR SELECTION FOR
CRYSTAL OSCILLATOR –
PIC12F508/509/16F505(2)
Osc
Type
Resonator
Freq.
Cap. Range
C1
Cap. Range
C2
LP
32 kHz(1)
15 pF
15 pF
XT
200 kHz
1 MHz
4 MHz
47-68 pF
15 pF
15 pF
47-68 pF
15 pF
15 pF
20 MHz
15-47 pF
15-47 pF
HS(3)
Note 1:
2:
3:
7.2.3
FIGURE 7-3:
EXTERNAL PARALLEL
RESONANT CRYSTAL
OSCILLATOR CIRCUIT
+5V
To Other
Devices
10k
74AS04
4.7k
For VDD > 4.5V, C1 = C2 ≈ 30 pF is
recommended.
These values are for design guidance
only. Rs may be required to avoid overdriving crystals with low drive level specification. Since each crystal has its own
characteristics, the user should consult
the crystal manufacturer for appropriate
values of external components.
PIC16F505 only.
EXTERNAL CRYSTAL OSCILLATOR
CIRCUIT
PIC16F505
PIC12F508
PIC12F509
10k
XTAL
10k
20 pF
20 pF
Figure 7-4 shows a series resonant oscillator circuit.
This circuit is also designed to use the fundamental
frequency of the crystal. The inverter performs a 180degree phase shift in a series resonant oscillator
circuit. The 330 Ω resistors provide the negative
feedback to bias the inverters in their linear region.
FIGURE 7-4:
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 7-3 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.
CLKIN
74AS04
330
EXTERNAL SERIES
RESONANT CRYSTAL
OSCILLATOR CIRCUIT
To Other
Devices
330
74AS04
74AS04
74AS04
CLKIN
0.1 mF
XTAL
7.2.4
PIC16F505
PIC12F508
PIC12F509
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 7-5 shows how the R/C combination is connected to the PIC12F508/509/16F505 devices. For
REXT values below 3.0 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 5.0 kΩ and
100 kΩ.
DS41236C-page 42
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
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.
Section 10.0 “Electrical Characteristics” shows RC
frequency variation from part-to-part due to normal
process variation. The variation is larger for larger values of R (since leakage current variation will affect RC
frequency more for large R) and for smaller values of C
(since variation of input capacitance will affect RC
frequency more).
Also, see the Electrical Specifications section for
variation of oscillator frequency due to VDD for given
REXT/CEXT values, as well as frequency variation due
to operating temperature for given R, C and VDD
values.
FIGURE 7-5:
EXTERNAL RC
OSCILLATOR MODE
VDD
REXT
OSC1
OSCCAL, when written to with the calibration value, will
“trim” the internal oscillator to remove process variation
from the oscillator frequency.
Note:
Note:
PIC16F505
PIC12F508
PIC12F509
VSS
FOSC/4
Erasing the device will also erase the preprogrammed 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 PIC12F508/509/16F505 devices, only bits
<7:1> of OSCCAL are implemented. Bits CAL6-CAL0
are used for calibration. Adjusting CAL6-CAL0 from
‘0000000’ to ‘1111111’ changes the clock speed. See
Register 4-5 for more information.
N
CEXT
7.2.5
Internal
clock
In addition, a calibration instruction is programmed into
the last address of memory, which contains the calibration value for the internal RC oscillator. This location is
always uncode 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.
The 0 bit of OSCCAL is unimplemented
and should be written as ‘0’ when modifying OSCCAL for compatibility with future
devices.
OSC2/CLKOUT
INTERNAL 4 MHz RC OSCILLATOR
The internal RC oscillator provides a fixed 4 MHz (nominal) system clock at VDD = 5V and 25°C, (see
Section 10.0 “Electrical Characteristics” for
information on variation over voltage and temperature).
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 43
PIC12F508/509/16F505
7.3
7.3.1
Reset
The device differentiates between various kinds of
Reset:
•
•
•
•
•
•
Power-on Reset (POR)
MCLR Reset during normal operation
MCLR Reset during Sleep
WDT time-out Reset during normal operation
WDT time-out Reset during Sleep
Wake-up from Sleep on pin change
EXTERNAL CLOCK IN
For applications where a clock is already available
elsewhere, users may directly drive the PIC12F508/
509/16F505 devices provided that this external clock
source meets the AC/DC timing requirements listed in
Section 7.6 “Watchdog Timer (WDT)”. Figure 7-6
below shows how an external clock circuit should be
configured.
FIGURE 7-6:
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
Power-on Reset (POR), MCLR, WDT or Wake-up on
pin change Reset during normal operation. They are
not affected by a WDT Reset during Sleep or MCLR
Reset during Sleep, since these Resets are viewed as
resumption of normal operation. The exceptions to this
are TO, PD and RBWUF/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 7-4 for a full description of Reset
states of all registers.
EXTERNAL CLOCK INPUT
OPERATION
PIC16F505: EC, HS, XT, LP
Clock From
ext. system
RB5/OSC1/CLKIN
PIC16F505
PIC12F508/509: XT, LP
Clock From
ext. system
GP5/OSC1/CLKIN
PIC12F508
PIC12F509
GP4/OSC2
OSC2
Note 1:
TABLE 7-3:
Register
W
OSC2/CLKOUT/RB4(1)
OSC2/CLKOUT/RB4
RB4 is available in EC mode only.
RESET CONDITIONS FOR REGISTERS – PIC12F508/509
Address
—
Power-on Reset
MCLR Reset, WDT Time-out,
Wake-up On Pin Change
qqqq qqqu(1)
qqqq qqqu(1)
INDF
00h
xxxx xxxx
uuuu uuuu
TMR0
01h
xxxx xxxx
uuuu uuuu
PC
02h
1111 1111
1111 1111
STATUS
03h
0001 1xxx
q00q quuu(2), (3)
FSR(4)
04h
110x xxxx
11uu uuuu
FSR(5)
04h
111x xxxx
111u uuuu
OSCCAL
05h
1111 111-
uuuu uuu-
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.
2: See Table 7-8 for Reset value for specific conditions.
3: If Reset was due to wake-up on pin change, then bit 7 = 1. All other Resets will cause bit 7 = 0.
4: PIC12F509 only.
5: PIC12F508 only.
DS41236C-page 44
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
TABLE 7-4:
RESET CONDITIONS FOR REGISTERS – PIC16F505
Register
Address
Power-on Reset
MCLR Reset, WDT Time-out,
Wake-up On Pin Change
qqqq qqqu(1)
qqqq qqqu(1)
00h
xxxx xxxx
uuuu uuuu
TMR0
01h
xxxx xxxx
uuuu uuuu
PC
02h
1111 1111
1111 1111
STATUS
03h
0001 1xxx
q00q quuu(2), (3)
FSR
04h
110x xxxx
11uu uuuu
OSCCAL
05h
1111 111-
uuuu uuu-
PORTB
06h
--xx xxxx
--uu uuuu
PORTC
07h
--xx xxxx
--uu uuuu
OPTION
—
1111 1111
1111 1111
TRISB
—
--11 1111
--11 1111
TRISC
—
--11 1111
--11 1111
W
—
INDF
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.
2: See Table 7-8 for Reset value for specific conditions.
3: If Reset was due to wake-up on pin change, then bit 7 = 1. All other Resets will cause bit 7 = 0.
TABLE 7-5:
RESET CONDITION FOR SPECIAL REGISTERS
STATUS Addr: 03h
PCL Addr: 02h
Power-on Reset
0001 1xxx
1111 1111
MCLR Reset during normal operation
000u uuuu
1111 1111
MCLR Reset during Sleep
0001 0uuu
1111 1111
WDT Reset during Sleep
0000 0uuu
1111 1111
WDT Reset normal operation
0000 uuuu
1111 1111
Wake-up from Sleep on pin change
1001 0uuu
1111 1111
Legend: u = unchanged, x = unknown, – = unimplemented bit, read as ‘0’.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 45
PIC12F508/509/16F505
7.3.2
MCLR ENABLE
This configuration bit, when unprogrammed (left in the
‘1’ state), enables the external MCLR function. When
programmed, the MCLR function is tied to the internal
VDD and the pin is assigned to be a I/O. See Figure 7-7.
FIGURE 7-7:
MCLR SELECT
GPWU/RBWU
(GP3/RB3)/MCLR/VPP
Internal MCLR
MCLRE
7.4
Power-on Reset (POR)
The PIC12F508/509/16F505 devices incorporate an
on-chip Power-on 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
VDD has reached a high enough level for proper operation. To take advantage of the internal POR, program
the (GP3/RB3)/MCLR/VPP pin as MCLR and tie
through a resistor to VDD, or program the pin as (GP3/
RB3). An internal weak pull-up resistor is implemented
using a transistor (refer to Table 10-2 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 VDD is specified. See
Section 10.0 “Electrical Characteristics” for details.
When the devices start normal operation (exit the
Reset condition), device operating parameters (voltage, frequency, temperature,...) must be met to ensure
operation. If these conditions are not met, the devices
must be held in Reset until the operating parameters
are met.
The Power-on Reset circuit and the Device Reset
Timer (see Section 7.5 “Device Reset Timer (DRT)”)
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 on-chip Reset signal.
A power-up example where MCLR is held low is shown
in Figure 7-9. VDD is allowed to rise and stabilize before
bringing MCLR high. The chip will actually come out of
Reset TDRT msec after MCLR goes high.
In Figure 7-10, the on-chip Power-on Reset feature is
being used (MCLR and VDD are tied together or the pin
is programmed to be (GP3/RB3). The VDD is stable
before the start-up timer times out and there is no problem in getting a proper Reset. However, Figure 7-11
depicts a problem situation where VDD 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, VDD has not reached the VDD (min)
value and the chip may not 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 devices start normal operation
(exit the Reset condition), device operating parameters (voltage, frequency, temperature, etc.) must be met 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
AN522 “Power-Up Considerations” (DS00522) and
AN607 “Power-up Trouble Shooting” (DS00607).
A simplified block diagram of the on-chip Power-on
Reset circuit is shown in Figure 7-8.
DS41236C-page 46
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
FIGURE 7-8:
SIMPLIFIED BLOCK DIAGRAM OF ON-CHIP RESET CIRCUIT
VDD
Power-up
Detect
POR (Power-on Reset)
(GP3/RB3)/MCLR/VPP
MCLR Reset
MCLRE
WDT Reset
WDT Time-out
S
Q
R
Q
Start-up Timer
CHIP Reset
(10 μs or 18 ms)
Pin Change
Sleep
Wake-up on pin Change Reset
FIGURE 7-9:
TIME-OUT SEQUENCE ON POWER-UP (MCLR PULLED LOW)
VDD
MCLR
Internal POR
TDRT
DRT Time-out
Internal Reset
TIME-OUT SEQUENCE ON POWER-UP (MCLR TIED TO VDD): FAST VDD RISE
TIME
FIGURE 7-10:
VDD
MCLR
Internal POR
TDRT
DRT Time-out
Internal Reset
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 47
PIC12F508/509/16F505
FIGURE 7-11:
TIME-OUT SEQUENCE ON POWER-UP (MCLR TIED TO VDD): SLOW VDD RISE
TIME
V1
VDD
MCLR
Internal POR
TDRT
DRT Time-out
Internal Reset
Note:
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.
DS41236C-page 48
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
7.5
TABLE 7-6:
Device Reset Timer (DRT)
On the PIC12F508/509/16F505 devices, the DRT runs
any time the device is powered up. DRT runs from
Reset and varies based on oscillator selection and
Reset type (see Table 7-6).
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 VDD to rise above VDD min. and
for the oscillator to stabilize.
Oscillator circuits based on crystals or ceramic resonators require a certain time after power-up to establish a
stable oscillation. The on-chip DRT keeps the devices in
a Reset condition for approximately 18 ms after MCLR
has reached a logic high (VIH MCLR) level.
Programming (GP3/RB3)/MCLR/VPP as MCLR and
using an external RC network connected to the MCLR
input is not required in most cases. This allows savings
in cost-sensitive and/or space restricted applications, as
well as allowing the use of the (GP3/RB3)/MCLR/VPP
pin as a general purpose input.
The Device Reset Time delays will vary from chip-tochip due to VDD, temperature and process variation.
See AC parameters for details.
The DRT will also be triggered upon a Watchdog Timer
time-out from Sleep. This is particularly important for
applications using the WDT to wake from Sleep mode
automatically.
Reset sources are POR, MCLR, WDT time-out and
wake-up on pin change. See Section 7.9.2 “Wake-up
from Sleep”, Notes 1, 2 and 3.
7.6
DRT (DEVICE RESET TIMER
PERIOD)
Oscillator
Configuration
POR Reset
Subsequent
Resets
INTOSC, EXTRC
18 ms (typical)
10 μs (typical)
HS(1)
18 ms (typical)
18 ms (typical)
18 ms (typical)
10 μs (typical)
, XT, LP
(1)
EC
Note 1:
7.6.1
PIC16F505 only.
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, VDD and part-to-part process variations (see DC specs).
Under worst case conditions (VDD = Min., Temperature
= Max., max. WDT prescaler), it may take several
seconds before a WDT time-out occurs.
7.6.2
WDT PROGRAMMING
CONSIDERATIONS
The CLRWDT instruction clears the WDT and the
postscaler, if assigned to the WDT, and prevents it from
timing out and generating a device Reset.
The SLEEP instruction resets the WDT and the
postscaler, if assigned to the WDT. This gives the
maximum Sleep time before a WDT wake-up Reset.
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/RB5)/OSC1/CLKIN
pin and the internal 4 MHz oscillator. This 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 TO bit (STATUS<4>) will be cleared upon a
Watchdog Timer Reset.
The WDT can be permanently disabled by programming the configuration WDTE as a ‘0’ (see Section 7.1
“Configuration Bits”). Refer to the PIC12F508/509/
16F505 Programming Specifications to determine how
to access the Configuration Word.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 49
PIC12F508/509/16F505
FIGURE 7-12:
WATCHDOG TIMER BLOCK DIAGRAM
From Timer0 Clock Source
(Figure 6-5)
0
1
Watchdog
Time
M
U
X
Postscaler
8-to-1 MUX
PS<2:0>
PSA
WDT Enable
Configuration
Bit
To Timer0 (Figure 6-4)
0
1
MUX
PSA
WDT Time-out
Note 1:
TABLE 7-7:
Address
T0CS, T0SE, PSA, PS<2:0> are bits in the OPTION register.
SUMMARY OF REGISTERS ASSOCIATED WITH THE WATCHDOG TIMER
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
Power-On
Reset
Value on
All Other
Resets
N/A
OPTION(1) GPWU
GPPU
T0CS
T0SE
PSA
PS2
PS1
PS0
1111 1111
1111 1111
N/A
OPTION(2)
RBPU
T0CS
T0SE
PSA
PS2
PS1
PS0
1111 1111
1111 1111
RBWU
Legend: Shaded boxes = Not used by Watchdog Timer. – = unimplemented, read as ‘0’, u = unchanged.
Note 1: PIC12F508/509 only.
2: PIC16F505 only.
DS41236C-page 50
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
7.7
Time-out Sequence, Power-down
and Wake-up from Sleep Status
Bits (TO, PD, GPWUF/RBWUF)
FIGURE 7-14:
VDD
VDD
The TO, PD and (GPWUF/RBWUF) bits in the STATUS
register can be tested to determine if a Reset condition
has been caused by a Power-up condition, a MCLR or
Watchdog Timer (WDT) Reset.
TABLE 7-8:
R1
TO
PD
0
0
0
WDT wake-up from Sleep
0
0
u
WDT time-out (not from
Sleep)
0
1
0
MCLR wake-up from Sleep
0
1
1
Power-up
Reset Caused By
Note 1:
40k(1)
This brown-out circuit is less expensive,
although less accurate. Transistor Q1 turns
off when VDD is below a certain level such
that:
R1
VDD •
2:
0
u
u
MCLR not during Sleep
1
1
0
Wake-up from Sleep on pin
change
To reset PIC12F508/509/16F505 devices when a
brown-out occurs, external brown-out protection
circuits may be built, as shown in Figure 7-13 and
Figure 7-14.
BROWN-OUT
PROTECTION CIRCUIT 3
VDD
MCP809
VSS
RST
Reset on Brown-out
A brown-out is a condition where device power (VDD)
dips below its minimum value, but not to zero, and then
recovers. The device should be reset in the event of a
brown-out.
= 0.7V
R1 + R2
Pin must be confirmed as MCLR.
FIGURE 7-15:
Legend: u = unchanged
Note 1: The TO, PD and GPWUF/RBWUF bits
maintain their status (u) until a Reset
occurs. A low-pulse on the MCLR input
does not change the TO, PD and
GPWUF/RBWUF Status bits.
FIGURE 7-13:
PIC16F505
PIC12F508
Q1
MCLR(2) PIC12F509
R2
TO/PD/(GPWUF/RBWUF)
STATUS AFTER RESET
GPWUF/
RBWUF
7.8
BROWN-OUT
PROTECTION CIRCUIT 2
Bypass
Capacitor
VDD
VDD
MCLR
PIC16F505
PIC12F508
PIC12F509
Note:
This brown-out protection circuit employs
Microchip Technology’s MCP809 microcontroller supervisor. There are 7 different
trip point selections to accommodate 5V to
3V systems.
BROWN-OUT
PROTECTION CIRCUIT 1
VDD
VDD
33k
10k
Q1
MCLR
PIC16F505
PIC12F508
(2) PIC12F509
40k(1)
Note 1:
2:
This circuit will activate Reset when VDD goes
below Vz + 0.7V (where Vz = Zener voltage).
Pin must be confirmed as MCLR.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 51
PIC12F508/509/16F505
7.9
Power-down Mode (Sleep)
7.10
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 TO bit (STATUS<4>) is set, the PD
bit (STATUS<3>) is cleared and the oscillator driver is
turned off. The I/O ports maintain the status they had
before the SLEEP instruction was executed (driving
high, driving low or high-impedance).
Note:
A Reset generated by a WDT time-out
does not drive the MCLR pin low.
For lowest current consumption while powered down,
the T0CKI input should be at VDD or VSS and the
(GP3/RB3)/MCLR/VPP pin must be at a logic high
level if MCLR is enabled.
7.9.2
WAKE-UP FROM SLEEP
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 (OSCCAL)
can be read, regardless of the code protection bit
setting.
The last memory location can be read regardless of the
code protection bit setting on the PIC12F508/509/
16F505 devices.
7.11
ID Locations
Four memory locations are designated as ID locations
where the user can store checksum or other code
identification 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.
The device can wake-up from Sleep through one of
the following events:
7.12
1.
The PIC12F508/509/16F505 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.
2.
3.
An external Reset input on (GP3/RB3)/MCLR/
VPP pin, when configured as MCLR.
A Watchdog Timer time-out Reset (if WDT was
enabled).
A change on input pin GP0/RB0, GP1/RB1,
GP3/RB3 or RB4 when wake-up on change is
enabled.
These events cause a device Reset. The TO, PD and
GPWUF/RBWUF bits can be used to determine the
cause of device Reset. The TO bit is cleared if a WDT
time-out occurred (and caused wake-up). The PD bit,
which is set on power-up, is cleared when SLEEP is
invoked. The GPWUF/RBWUF bit indicates a change
in state while in Sleep at pins GP0/RB0, GP1/RB1,
GP3/RB3 or RB4 (since the last file or bit operation on
GP/RB port).
Note:
Caution: Right before entering Sleep,
read the input pins. When in Sleep, wakeup 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.
In-Circuit Serial Programming™
The devices are placed into a Program/Verify mode by
holding the GP1/RB1 and GP0/RB0 pins low while raising the MCLR (VPP) pin from VIL to VIHH (see programming
specification).
GP1/RB1
becomes
the
programming clock and GP0/RB0 becomes the
programming data. Both GP1/RB1 and GP0/RB0 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
PIC12F508/509/16F505 Programming Specifications.
A typical In-Circuit Serial Programming connection is
shown in Figure 7-16.
The WDT is cleared when the device wakes from
Sleep, regardless of the wake-up source.
DS41236C-page 52
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
FIGURE 7-16:
External
Connector
Signals
TYPICAL IN-CIRCUIT
SERIAL PROGRAMMING
CONNECTION
To Normal
Connections
PIC16F505
PIC12F508
PIC12F509
+5V
VDD
0V
VSS
VPP
MCLR/VPP
CLK
GP1/RB1
Data I/O
GP0/RB0
VDD
To Normal
Connections
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 53
PIC12F508/509/16F505
NOTES:
DS41236C-page 54
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
8.0
INSTRUCTION SET SUMMARY
The PIC16 instruction set is highly orthogonal and is
comprised of three basic categories.
• Byte-oriented operations
• Bit-oriented operations
• Literal and control operations
Each PIC16 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 formats for each of the categories is presented in Figure 8-1, while the various
opcode fields are summarized in Table 8-1.
For byte-oriented instructions, ‘f’ represents a file register designator and ‘d’ represents a destination designator. The file register designator specifies which file
register 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.
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:
Byte-oriented file register operations
11
Bit-oriented file register operations
11
OPCODE
11
Register file address (0x00 to 0x7F)
W
Working register (accumulator)
b
Bit address within an 8-bit file register
k
Literal field, constant data or label
x
Don’t care location (= 0 or 1)
The assembler will generate code with x = 0. It is
the recommended form of use for compatibility with
all Microchip software tools.
Label name
Top-of-Stack
PC
WDT
PD
Power-down bit
0
k (literal)
Literal and control operations – GOTO instruction
11
9
8
OPCODE
0
k (literal)
k = 9-bit immediate value
Destination, either the W register or the specified
register file location
[
]
Options
(
)
Contents
italics
7
k = 8-bit immediate value
dest
∈
8
Watchdog Timer counter
Time-out bit
< >
0
f (FILE #)
Program Counter
TO
→
8 7
5 4
b (BIT #)
OPCODE
Destination select;
d = 0 (store result in W)
d = 1 (store result in file register ‘f’)
Default is d = 1
TOS
0
f (FILE #)
Literal and control operations (except GOTO)
Description
label
4
b = 3-bit bit address
f = 5-bit file register address
f
d
5
d
d = 0 for destination W
d = 1 for destination f
f = 5-bit file register address
OPCODE FIELD
DESCRIPTIONS
Field
6
OPCODE
For literal and control operations, ‘k’ represents an
8 or 9-bit constant or literal value.
TABLE 8-1:
GENERAL FORMAT FOR
INSTRUCTIONS
Assigned to
Register bit field
In the set of
User defined term (font is courier)
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 55
PIC12F508/509/16F505
TABLE 8-2:
INSTRUCTION SET SUMMARY
Mnemonic,
Operands
ADDWF
ANDWF
CLRF
CLRW
COMF
DECF
DECFSZ
INCF
INCFSZ
IORWF
MOVF
MOVWF
NOP
RLF
RRF
SUBWF
SWAPF
XORWF
12-Bit Opcode
Description
Cycles
MSb
LSb
Status
Notes
Affected
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
0001 11df ffff C, DC, Z 1, 2, 4
Add W and f
1
0001 01df ffff
AND W with f
1
Z
2, 4
0000 011f ffff
Clear f
1
Z
4
0000 0100 0000
Clear W
1
Z
0010 01df ffff
Complement f
1
Z
0000 11df ffff
Decrement f
1
Z
2, 4
0010 11df ffff
Decrement f, Skip if 0
1(2)
None
2, 4
1
0010 10df ffff
Increment f
Z
2, 4
1(2)
0011 11df ffff
Increment f, Skip if 0
None
2, 4
1
0001 00df ffff
Inclusive OR W with f
Z
2, 4
1
0010 00df ffff
Move f
Z
2, 4
1
0000 001f ffff
Move W to f
None
1, 4
1
0000 0000 0000
No Operation
None
1
0011 01df ffff
Rotate left f through Carry
C
2, 4
1
0011 00df ffff
Rotate right f through Carry
C
2, 4
1
0000 10df ffff C, DC, Z 1, 2, 4
Subtract W from f
1
0011 10df ffff
Swap f
None
2, 4
1
0001 10df ffff
Exclusive OR W with f
Z
2, 4
BIT-ORIENTED FILE REGISTER OPERATIONS
0100 bbbf ffff
None
2, 4
1
Bit Clear f
BCF
f, b
0101 bbbf ffff
None
2, 4
1
Bit Set f
BSF
f, b
0110 bbbf ffff
None
Bit Test f, Skip if Clear
1(2)
BTFSC
f, b
1(2)
0111 bbbf ffff
None
f, b
Bit Test f, Skip if Set
BTFSS
LITERAL AND CONTROL OPERATIONS
ANDLW
k
AND literal with W
1
1110 kkkk kkkk
Z
CALL
1
k
Call Subroutine
2
1001 kkkk kkkk
None
CLRWDT
—
Clear Watchdog Timer
1
0000 0000 0100 TO, PD
None
GOTO
k
Unconditional branch
2
101k kkkk kkkk
Z
IORLW
k
Inclusive OR literal with W
1
1101 kkkk kkkk
None
MOVLW
k
Move literal to W
1
1100 kkkk kkkk
None
OPTION
—
Load OPTION register
1
0000 0000 0010
None
RETLW
k
Return, place literal in W
2
1000 kkkk kkkk
SLEEP
—
Go into Standby mode
1
0000 0000 0011 TO, PD
None
3
TRIS
f
Load TRIS register
1
0000 0000 0fff
Z
XORLW
k
Exclusive OR literal to W
1
1111 kkkk kkkk
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. See Section 4.7 “Program Counter”.
2: When an I/O register is modified as a function of itself (e.g. MOVF PORTB, 1), the value used will be that
value present on the pins themselves. For example, if the data latch is ‘1’ for a pin configured as input and
is driven low by an external device, the data will be written back with a ‘0’.
3: The instruction TRIS f, where f = 6, causes the contents of the W register to be written to the tri-state
latches of PORTB. A ‘1’ forces the pin to a high-impedance state and disables the output buffers.
4: If this instruction is executed on the TMR0 register (and, where applicable, d = 1), the prescaler will be
cleared (if assigned to TMR0).
DS41236C-page 56
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
ADDWF
Add W and f
BCF
Syntax:
[ label ] ADDWF
Syntax:
[ label ] BCF
Operands:
0 ≤ f ≤ 31
d ∈ [0,1]
Operands:
0 ≤ f ≤ 31
0≤b≤7
Operation:
(W) + (f) → (dest)
Operation:
0 → (f<b>)
Status Affected: C, DC, Z
Status Affected:
None
Description:
Description:
Bit ‘b’ in register ‘f’ is cleared.
BSF
Bit Set f
Syntax:
[ label ] BSF
Operands:
0 ≤ f ≤ 31
0≤b≤7
Status Affected: Z
Operation:
1 → (f<b>)
Description:
The contents of the W register are
AND’ed with the eight-bit literal ‘k’.
The result is placed in the W
register.
Status Affected:
None
ANDWF
AND W with f
BTFSC
Syntax:
[ label ] ANDWF
Operands:
Operation:
ANDLW
Syntax:
f,d
Bit Clear f
Add the contents of the W register
and register ‘f’. If ‘d’ is’0’, the result
is stored in the W register. If ‘d’ is
‘1’, the result is stored back in
register ‘f’.
AND literal with W
[ label ] ANDLW
k
Operands:
0 ≤ k ≤ 255
Operation:
(W).AND. (k) → (W)
f,b
f,b
Description: Bit ‘b’ in register ‘f’ is set.
Bit Test f, Skip if Clear
Syntax:
[ label ] BTFSC f,b
0 ≤ f ≤ 31
d ∈ [0,1]
Operands:
0 ≤ f ≤ 31
0≤b≤7
(W) .AND. (f) → (dest)
Operation:
skip if (f<b>) = 0
Status Affected: Z
Status Affected:
None
Description:
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 a NOP is executed instead,
making this a two-cycle instruction.
f,d
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’.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 57
PIC12F508/509/16F505
BTFSS
Bit Test f, Skip if Set
CLRW
Syntax:
[ label ] BTFSS f,b
Syntax:
[ label ] CLRW
0 ≤ f ≤ 31
0≤b<7
Operands:
None
Operation:
00h → (W);
1→Z
Operands:
Clear W
Operation:
skip if (f<b>) = 1
Status Affected:
None
Status Affected:
Z
Description:
If bit ‘b’ in register ‘f’ is ‘1’, then the
next instruction is skipped.
If bit ‘b’ is ‘1’, then the next instruction fetched during the current
instruction execution, is discarded
and a NOP is executed instead,
making this a two-cycle instruction.
Description:
The W register is cleared. Zero bit
(Z) is set.
CALL
Subroutine Call
CLRWDT
Clear Watchdog Timer
Syntax:
[ label ] CALL k
Syntax:
[ label ] CLRWDT
Operands:
0 ≤ k ≤ 255
Operands:
None
Operation:
(PC) + 1→ Top-of-Stack;
k → PC<7:0>;
(STATUS<6:5>) → PC<10:9>;
0 → PC<8>
Operation:
00h → WDT;
0 → WDT prescaler (if assigned);
1 → TO;
1 → PD
Status Affected:
None
Status Affected:
TO, PD
Description:
Subroutine call. First, return
address (PC + 1) is PUSHed onto
the stack. The eight-bit immediate
address is loaded into PC
bits <7:0>. The upper bits
PC<10:9> are loaded from
STATUS<6:5>, PC<8> is cleared.
CALL is a two-cycle instruction.
Description:
The CLRWDT instruction resets the
WDT. It also resets the prescaler, if
the prescaler is assigned to the
WDT and not Timer0. Status bits
TO and PD are set.
CLRF
Clear f
COMF
Complement f
Syntax:
[ label ] CLRF
Syntax:
[ label ] COMF
Operands:
0 ≤ f ≤ 31
Operands:
Operation:
00h → (f);
1→Z
0 ≤ f ≤ 31
d ∈ [0,1]
Operation:
(f) → (dest)
Status Affected:
Z
Status Affected:
Z
Description:
The contents of register ‘f’ are
cleared and the Z bit is set.
Description:
The contents of register ‘f’ are
complemented. If ‘d’ is ‘0’, the
result is stored in the W register. If
‘d’ is ‘1’, the result is stored back in
register ‘f’.
DS41236C-page 58
f
Preliminary
f,d
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
DECF
Decrement f
INCF
Syntax:
[ label ] DECF f,d
Syntax:
[ label ]
Operands:
0 ≤ f ≤ 31
d ∈ [0,1]
Operands:
0 ≤ f ≤ 31
d ∈ [0,1]
Operation:
(f) – 1 → (dest)
Operation:
(f) + 1 → (dest)
Status Affected:
Z
Status Affected:
Z
Description:
Decrement register ‘f’. If ‘d’ is ‘0’,
the result is stored in the W
register. If ‘d’ is ‘1’, the result is
stored back in register ‘f’.
Description:
The contents of register ‘f’ are
incremented. If ‘d’ is ‘0’, the result
is placed in the W register. If ‘d’ is
‘1’, the result is placed back in
register ‘f’.
DECFSZ
Decrement f, Skip if 0
INCFSZ
Increment f, Skip if 0
Syntax:
[ label ] DECFSZ f,d
Syntax:
[ label ]
Operands:
0 ≤ f ≤ 31
d ∈ [0,1]
Operands:
0 ≤ f ≤ 31
d ∈ [0,1]
Operation:
(f) – 1 → d;
Operation:
(f) + 1 → (dest), skip if result = 0
Status Affected:
None
Status Affected:
None
Description:
The contents of register ‘f’ are
decremented. 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 a NOP is executed
instead making it a two-cycle
instruction.
Description:
The contents of register ‘f’ are
incremented. 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
instruction, which is already
fetched, is discarded and a NOP is
executed instead making it a
two-cycle instruction.
GOTO
Unconditional Branch
IORLW
Inclusive OR literal with W
Syntax:
[ label ]
Syntax:
[ label ]
Operands:
0 ≤ k ≤ 511
Operands:
0 ≤ k ≤ 255
Operation:
k → PC<8:0>;
STATUS<6:5> → PC<10:9>
Operation:
(W) .OR. (k) → (W)
Status Affected:
Z
Status Affected:
None
Description:
Description:
GOTO is an unconditional branch.
The 9-bit immediate value is
loaded into PC bits <8:0>. The
upper bits of PC are loaded from
STATUS<6:5>. GOTO is a twocycle instruction.
The contents of the W register are
OR’ed with the eight-bit literal ‘k’.
The result is placed in the
W register.
skip if result = 0
GOTO k
© 2007 Microchip Technology Inc.
Preliminary
Increment f
INCF f,d
INCFSZ f,d
IORLW k
DS41236C-page 59
PIC12F508/509/16F505
IORWF
Inclusive OR W with f
MOVWF
Syntax:
[ label ]
Syntax:
[ label ]
Operands:
0 ≤ f ≤ 31
d ∈ [0,1]
Operands:
0 ≤ f ≤ 31
Operation:
(W).OR. (f) → (dest)
(W) → (f)
Operation:
Status Affected:
None
Status Affected:
Z
Description:
Description:
Inclusive OR the W register with
register ‘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’.
Move data from the W register to
register ‘f’.
MOVF
Move f
NOP
No Operation
Syntax:
[ label ]
Syntax:
[ label ]
Operands:
0 ≤ f ≤ 31
d ∈ [0,1]
Operands:
None
Operation:
No operation
IORWF
f,d
MOVF f,d
Move W to f
MOVWF
f
NOP
Operation:
(f) → (dest)
Status Affected:
None
Status Affected:
Z
Description:
No operation.
Description:
The contents of register ‘f’ are
moved to destination ‘d’. If ‘d’ is ‘0’,
destination is the W register. If ‘d’
is ‘1’, the destination is file
register ‘f’. ‘d’ = 1 is useful as a
test of a file register, since status
flag Z is affected.
MOVLW
Move Literal to W
OPTION
Load OPTION Register
Syntax:
[ label ]
Syntax:
[ label ]
Operands:
0 ≤ k ≤ 255
Operands:
None
Operation:
k → (W)
Operation:
(W) → OPTION
Status Affected:
None
Status Affected:
None
Description:
The content of the W register is
loaded into the OPTION register.
Description:
DS41236C-page 60
MOVLW k
The eight-bit literal ‘k’ is loaded
into the W register. The “don’t
cares” will assembled as ‘0’s.
Preliminary
OPTION
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
RETLW
Return with Literal in W
SLEEP
Enter SLEEP Mode
Syntax:
[ label ]
Syntax:
[label ]
Operands:
0 ≤ k ≤ 255
Operands:
None
Operation:
k → (W);
TOS → PC
Operation:
00h → WDT;
0 → WDT prescaler;
1 → TO;
0 → PD
Status Affected:
TO, PD, RBWUF
Description:
Time-out Status bit (TO) is set. The
Power-down Status bit (PD) is
cleared.
RBWUF is unaffected.
The WDT and its prescaler are
cleared.
The processor is put into Sleep
mode with the oscillator stopped.
See Section 7.9 “Power-down
Mode (Sleep)” on Sleep for more
details.
SUBWF
Subtract W from f
RETLW k
Status Affected:
None
Description:
The W register is loaded with the
eight-bit literal ‘k’. The program
counter is loaded from the top of
the stack (the return address). This
is a two-cycle instruction.
RLF
Rotate Left f through Carry
Syntax:
[ label ]
Operands:
0 ≤ f ≤ 31
d ∈ [0,1]
RLF
f,d
SLEEP
Syntax:
[label ]
Operands:
0 ≤ f ≤ 31
d ∈ [0,1]
SUBWF f,d
Operation:
See description below
Status Affected:
C
Operation:
(f) – (W) → (dest)
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’.
Status Affected:
C, DC, Z
Description:
Subtract (2’s complement method)
the W register from register ‘f’. If ‘d’
is ‘0’, the result is stored in the W
register. If ‘d’ is ‘1’, the result is
stored back in register ‘f’.
SWAPF
Swap Nibbles in f
Syntax:
[ label ] SWAPF f,d
Operands:
0 ≤ f ≤ 31
d ∈ [0,1]
Operation:
(f<3:0>) → (dest<7:4>);
(f<7:4>) → (dest<3:0>)
Status Affected:
None
Description:
The upper and lower nibbles of
register ‘f’ are exchanged. If ‘d’ is
‘0’, the result is placed in W
register. If ‘d’ is ‘1’, the result is
placed in register ‘f’.
Description:
register ‘f’
C
RRF
Rotate Right f through Carry
Syntax:
[ label ]
Operands:
0 ≤ f ≤ 31
d ∈ [0,1]
Operation:
See description below
Status Affected:
C
Description:
The contents of register ‘f’ are
rotated one bit to the right through
the Carry flag. If ‘d’ is ‘0’, the result
is placed in the W register. If ‘d’ is
‘1’, the result is placed back in
register ‘f’.
RRF f,d
C
© 2007 Microchip Technology Inc.
register ‘f’
Preliminary
DS41236C-page 61
PIC12F508/509/16F505
TRIS
Load TRIS Register
XORWF
Syntax:
[ label ] TRIS
Syntax:
[ label ] XORWF
Operands:
f=6
Operands:
Operation:
(W) → TRIS register f
0 ≤ f ≤ 31
d ∈ [0,1]
f
Exclusive OR W with f
f,d
Status Affected:
None
Operation:
(W) .XOR. (f) → (dest)
Description:
TRIS register ‘f’ (f = 6 or 7) is
loaded with the contents of the W
register
Status Affected:
Z
Description:
Exclusive OR the contents of the
W register with register ‘f’. If ‘d’ is
‘0’, the result is stored in the W
register. If ‘d’ is ‘1’, the result is
stored back in register ‘f’.
XORLW
Exclusive OR literal with W
Syntax:
[label ]
Operands:
0 ≤ k ≤ 255
Operation:
(W) .XOR. k → (W)
Status Affected:
Z
Description:
The contents of the W register are
XOR’ed with the eight-bit literal ‘k’.
The result is placed in the W
register.
DS41236C-page 62
XORLW k
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
9.0
DEVELOPMENT SUPPORT
9.1
The PIC® microcontrollers are supported with a full
range of hardware and software development tools:
• Integrated Development Environment
- MPLAB® IDE Software
• Assemblers/Compilers/Linkers
- MPASMTM Assembler
- MPLAB C18 and MPLAB C30 C Compilers
- MPLINKTM Object Linker/
MPLIBTM Object Librarian
- MPLAB ASM30 Assembler/Linker/Library
• Simulators
- MPLAB SIM Software Simulator
• Emulators
- MPLAB ICE 2000 In-Circuit Emulator
- MPLAB REAL ICE™ In-Circuit Emulator
• In-Circuit Debugger
- MPLAB ICD 2
• Device Programmers
- PICSTART® Plus Development Programmer
- MPLAB PM3 Device Programmer
- PICkit™ 2 Development Programmer
• Low-Cost Demonstration and Development
Boards and Evaluation Kits
MPLAB Integrated Development
Environment Software
The MPLAB IDE software brings an ease of software
development previously unseen in the 8/16-bit microcontroller market. The MPLAB IDE is a Windows®
operating system-based application that contains:
• A single graphical interface to all debugging tools
- Simulator
- Programmer (sold separately)
- Emulator (sold separately)
- In-Circuit Debugger (sold separately)
• A full-featured editor with color-coded context
• A multiple project manager
• Customizable data windows with direct edit of
contents
• High-level source code debugging
• Visual device initializer for easy register
initialization
• Mouse over variable inspection
• Drag and drop variables from source to watch
windows
• Extensive on-line help
• Integration of select third party tools, such as
HI-TECH Software C Compilers and IAR
C Compilers
The MPLAB IDE allows you to:
• Edit your source files (either assembly or C)
• One touch assemble (or compile) and download
to PIC MCU emulator and simulator tools
(automatically updates all project information)
• Debug using:
- Source files (assembly or C)
- Mixed assembly and C
- Machine code
MPLAB IDE supports multiple debugging tools in a
single development paradigm, from the cost-effective
simulators, through low-cost in-circuit debuggers, to
full-featured emulators. This eliminates the learning
curve when upgrading to tools with increased flexibility
and power.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 63
PIC12F508/509/16F505
9.2
MPASM Assembler
9.5
The MPASM Assembler is a full-featured, universal
macro assembler for all PIC MCUs.
The MPASM Assembler generates relocatable object
files for the MPLINK Object Linker, Intel® standard HEX
files, MAP files to detail memory usage and symbol
reference, absolute LST files that contain source lines
and generated machine code and COFF files for
debugging.
The MPASM Assembler features include:
MPLAB ASM30 Assembler produces relocatable
machine code from symbolic assembly language for
dsPIC30F devices. MPLAB C30 C Compiler uses the
assembler to produce its object file. The assembler
generates relocatable object files that can then be
archived or linked with other relocatable object files and
archives to create an executable file. Notable features
of the assembler include:
•
•
•
•
•
•
• Integration into MPLAB IDE projects
• User-defined macros to streamline
assembly code
• Conditional assembly for multi-purpose
source files
• Directives that allow complete control over the
assembly process
Support for the entire dsPIC30F instruction set
Support for fixed-point and floating-point data
Command line interface
Rich directive set
Flexible macro language
MPLAB IDE compatibility
9.6
9.3
MPLAB C18 and MPLAB C30
C Compilers
The MPLAB C18 and MPLAB C30 Code Development
Systems are complete ANSI C compilers for
Microchip’s PIC18 and PIC24 families of microcontrollers and the dsPIC30 and dsPIC33 family of digital signal controllers. These compilers provide powerful
integration capabilities, superior code optimization and
ease of use not found with other compilers.
For easy source level debugging, the compilers provide
symbol information that is optimized to the MPLAB IDE
debugger.
9.4
MPLINK Object Linker/
MPLIB Object Librarian
The MPLINK Object Linker combines relocatable
objects created by the MPASM Assembler and the
MPLAB C18 C Compiler. It can link relocatable objects
from precompiled libraries, using directives from a
linker script.
MPLAB ASM30 Assembler, Linker
and Librarian
MPLAB SIM Software Simulator
The MPLAB SIM Software Simulator allows code
development in a PC-hosted environment by simulating the PIC MCUs and dsPIC® DSCs on an instruction
level. On any given instruction, the data areas can be
examined or modified and stimuli can be applied from
a comprehensive stimulus controller. Registers can be
logged to files for further run-time analysis. The trace
buffer and logic analyzer display extend the power of
the simulator to record and track program execution,
actions on I/O, most peripherals and internal registers.
The MPLAB SIM Software Simulator fully supports
symbolic debugging using the MPLAB C18 and
MPLAB C30 C Compilers, and the MPASM and
MPLAB ASM30 Assemblers. The software simulator
offers the flexibility to develop and debug code outside
of the hardware laboratory environment, making it an
excellent, economical software development tool.
The MPLIB Object Librarian manages the creation and
modification of library files of precompiled code. When
a routine from a library is called from a source file, only
the modules that contain that routine will be linked in
with the application. This allows large libraries to be
used efficiently in many different applications.
The object linker/library features include:
• Efficient linking of single libraries instead of many
smaller files
• Enhanced code maintainability by grouping
related modules together
• Flexible creation of libraries with easy module
listing, replacement, deletion and extraction
DS41236C-page 64
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
9.7
MPLAB ICE 2000
High-Performance
In-Circuit Emulator
9.9
The MPLAB ICE 2000 In-Circuit Emulator is intended
to provide the product development engineer with a
complete microcontroller design tool set for PIC
microcontrollers. Software control of the MPLAB ICE
2000 In-Circuit Emulator is advanced by the MPLAB
Integrated Development Environment, which allows
editing, building, downloading and source debugging
from a single environment.
The MPLAB ICE 2000 is a full-featured emulator
system with enhanced trace, trigger and data monitoring features. Interchangeable processor modules allow
the system to be easily reconfigured for emulation of
different processors. The architecture of the MPLAB
ICE 2000 In-Circuit Emulator allows expansion to
support new PIC microcontrollers.
The MPLAB ICE 2000 In-Circuit Emulator system has
been designed as a real-time emulation system with
advanced features that are typically found on more
expensive development tools. The PC platform and
Microsoft® Windows® 32-bit operating system were
chosen to best make these features available in a
simple, unified application.
9.8
MPLAB REAL ICE In-Circuit
Emulator System
MPLAB REAL ICE In-Circuit Emulator System is
Microchip’s next generation high-speed emulator for
Microchip Flash DSC® and MCU devices. It debugs and
programs PIC® and dsPIC® Flash microcontrollers with
the easy-to-use, powerful graphical user interface of the
MPLAB Integrated Development Environment (IDE),
included with each kit.
The MPLAB REAL ICE probe is connected to the design
engineer’s PC using a high-speed USB 2.0 interface and
is connected to the target with either a connector
compatible with the popular MPLAB ICD 2 system
(RJ11) or with the new high speed, noise tolerant, lowvoltage differential signal (LVDS) interconnection
(CAT5).
MPLAB ICD 2 In-Circuit Debugger
Microchip’s In-Circuit Debugger, MPLAB ICD 2, is a
powerful, low-cost, run-time development tool,
connecting to the host PC via an RS-232 or high-speed
USB interface. This tool is based on the Flash PIC
MCUs and can be used to develop for these and other
PIC MCUs and dsPIC DSCs. The MPLAB ICD 2 utilizes
the in-circuit debugging capability built into the Flash
devices. This feature, along with Microchip’s In-Circuit
Serial ProgrammingTM (ICSPTM) protocol, offers costeffective, in-circuit Flash debugging from the graphical
user interface of the MPLAB Integrated Development
Environment. This enables a designer to develop and
debug source code by setting breakpoints, single stepping and watching variables, and CPU status and
peripheral registers. Running at full speed enables
testing hardware and applications in real time. MPLAB
ICD 2 also serves as a development programmer for
selected PIC devices.
9.10
MPLAB PM3 Device Programmer
The MPLAB PM3 Device Programmer is a universal,
CE compliant device programmer with programmable
voltage verification at VDDMIN and VDDMAX for
maximum reliability. It features a large LCD display
(128 x 64) for menus and error messages and a modular, detachable socket assembly to support various
package types. The ICSP™ cable assembly is included
as a standard item. In Stand-Alone mode, the MPLAB
PM3 Device Programmer can read, verify and program
PIC devices without a PC connection. It can also set
code protection in this mode. The MPLAB PM3
connects to the host PC via an RS-232 or USB cable.
The MPLAB PM3 has high-speed communications and
optimized algorithms for quick programming of large
memory devices and incorporates an SD/MMC card for
file storage and secure data applications.
MPLAB REAL ICE is field upgradeable through future
firmware downloads in MPLAB IDE. In upcoming
releases of MPLAB IDE, new devices will be supported,
and new features will be added, such as software breakpoints and assembly code trace. MPLAB REAL ICE
offers significant advantages over competitive emulators
including low-cost, full-speed emulation, real-time
variable watches, trace analysis, complex breakpoints, a
ruggedized probe interface and long (up to three meters)
interconnection cables.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 65
PIC12F508/509/16F505
9.11
PICSTART Plus Development
Programmer
9.13
The PICSTART Plus Development Programmer is an
easy-to-use, low-cost, prototype programmer. It
connects to the PC via a COM (RS-232) port. MPLAB
Integrated Development Environment software makes
using the programmer simple and efficient. The
PICSTART Plus Development Programmer supports
most PIC devices in DIP packages up to 40 pins.
Larger pin count devices, such as the PIC16C92X and
PIC17C76X, may be supported with an adapter socket.
The PICSTART Plus Development Programmer is CE
compliant.
9.12
PICkit 2 Development Programmer
The PICkit™ 2 Development Programmer is a low-cost
programmer and selected Flash device debugger with
an easy-to-use interface for programming many of
Microchip’s baseline, mid-range and PIC18F families of
Flash memory microcontrollers. The PICkit 2 Starter Kit
includes a prototyping development board, twelve
sequential lessons, software and HI-TECH’s PICC™
Lite C compiler, and is designed to help get up to speed
quickly using PIC® microcontrollers. The kit provides
everything needed to program, evaluate and develop
applications using Microchip’s powerful, mid-range
Flash memory family of microcontrollers.
DS41236C-page 66
Demonstration, Development and
Evaluation Boards
A wide variety of demonstration, development and
evaluation boards for various PIC MCUs and dsPIC
DSCs allows quick application development on fully functional systems. Most boards include prototyping areas for
adding custom circuitry and provide application firmware
and source code for examination and modification.
The boards support a variety of features, including LEDs,
temperature sensors, switches, speakers, RS-232
interfaces, LCD displays, potentiometers and additional
EEPROM memory.
The demonstration and development boards can be
used in teaching environments, for prototyping custom
circuits and for learning about various microcontroller
applications.
In addition to the PICDEM™ and dsPICDEM™ demonstration/development board series of circuits, Microchip
has a line of evaluation kits and demonstration software
for analog filter design, KEELOQ® security ICs, CAN,
IrDA®, PowerSmart® battery management, SEEVAL®
evaluation system, Sigma-Delta ADC, flow rate
sensing, plus many more.
Check the Microchip web page (www.microchip.com)
and the latest “Product Selector Guide” (DS00148) for
the complete list of demonstration, development and
evaluation kits.
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
10.0
ELECTRICAL CHARACTERISTICS
Absolute Maximum Ratings(†)
Ambient temperature under bias.......................................................................................................... -40°C to +125°C
Storage temperature ............................................................................................................................ -65°C to +150°C
Voltage on VDD with respect to VSS ............................................................................................................... 0 to +6.5V
Voltage on MCLR with respect to VSS..........................................................................................................0 to +13.5V
Voltage on all other pins with respect to VSS ............................................................................... -0.3V to (VDD + 0.3V)
Total power dissipation(1) .................................................................................................................................. 800 mW
Max. current out of VSS pin ................................................................................................................................ 200 mA
Max. current into VDD pin ................................................................................................................................... 150 mA
Input clamp current, IIK (VI < 0 or VI > VDD)...................................................................................................................±20 mA
Output clamp current, IOK (VO < 0 or VO > VDD) ...........................................................................................................±20 mA
Max. output current sunk by any I/O pin .............................................................................................................. 25 mA
Max. output current sourced by any I/O pin ......................................................................................................... 25 mA
Max. output current sourced by I/O port .............................................................................................................. 75 mA
Max. output current sunk by I/O port ................................................................................................................... 75 mA
Note 1: Power dissipation is calculated as follows: PDIS = VDD x {IDD – ∑ IOH} + ∑ {(VDD – VOH) x IOH} + ∑(VOL x IOL)
†NOTICE:
Stresses above those listed under “Absolute 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.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 67
PIC12F508/509/16F505
PIC12F508/509/16F505 VOLTAGE-FREQUENCY GRAPH, -40°C ≤ TA ≤ +125°C
FIGURE 10-1:
6.0
5.5
5.0
VDD
(Volts)
4.5
4.0
3.5
3.0
2.5
2.0
0
4
10
20
25
Frequency (MHz)
FIGURE 10-2:
MAXIMUM OSCILLATOR FREQUENCY TABLE
Oscillator Mode
LP
XT
INTOSC
XTRC
EC
HS
0
200 kHz
4 MHz
20 MHz
Frequency (MHz)
DS41236C-page 68
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
10.1
DC Characteristics: PIC12F508/509/16F505 (Industrial)
DC CHARACTERISTICS
Standard Operating Conditions (unless otherwise specified)
Operating Temperature -40°C ≤ TA ≤ +85°C (industrial)
Param
No.
Min
Sym
Characteristic
Typ(1)
Max
Units
Conditions
D001
VDD
Supply Voltage
2.0
5.5
V
See Figure 10-1
D002
VDR
RAM Data Retention Voltage(2)
—
1.5*
—
V
Device in Sleep mode
D003
VPOR VDD Start Voltage to ensure
Power-on Reset
—
VSS
—
V
See Section 7.4 "DC Characteristics" for details
D004
SVDD
VDD Rise Rate to ensure
Power-on Reset
0.05
*
—
—
V/ms
See Section 7.4 "DC Characteristics" for details
D010
IDD
Supply Current(3)
—
—
—
—
170
0.4
1.7
15
TBD
TBD
TBD
TBD
μA
mA
mA
μA
FOSC = 4 MHz, VDD = 2.0V(4)
FOSC = 10 MHz, VDD = 3.0V
FOSC = 20 MHz, VDD = 5.0V
FOSC = 32 kHz, VDD = 2.0V, WDT
disabled
D020
IPD
Power-down Current(5)
—
0.1
TBD
μA
VDD = 2.0V
D022
ΔIWDT WDT Current(5)
—
1.0
TBD
μA
VDD = 2.0V
Legend: TBD = To Be Determined.
* 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
guidance only and is not tested.
2: This is the limit to which VDD 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 IDD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VSS, 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 (in EXTRC mode only). The current through the resistor can be
estimated by the formula:
I = VDD/2REXT (mA) with REXT in kΩ.
5: The Power-down current in Sleep mode does not depend on the oscillator type. Power-down current is
measured with the part in Sleep mode, with all I/O pins in high-impedance state and tied to VDD or VSS.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 69
PIC12F508/509/16F505
10.2
DC Characteristics: PIC12F508/509/16F505 (Extended)
DC CHARACTERISTICS
Param
No.
Sym
Characteristic
Standard Operating Conditions (unless otherwise specified)
Operating Temperature -40°C ≤ TA ≤ +125°C (Extended)
Min
Typ(1)
Max
Units
Conditions
D001
VDD
Supply Voltage
2.0
5.5
V
See Figure 10-1
D002
VDR
RAM Data Retention Voltage(2)
—
1.5*
—
V
Device in Sleep mode
D003
VPOR
VDD Start Voltage to ensure
Power-on Reset
—
VSS
—
V
See Section 7.4 "DC Characteristics" for details
D004
SVDD
VDD Rise Rate to ensure
Power-on Reset
0.05*
—
—
V/ms
See Section 7.4 "DC Characteristics" for details
D010
IDD
Supply Current(3)
—
—
—
—
170
0.4
1.7
15
TBD
TBD
TBD
TBD
μA
mA
mA
μA
FOSC = 4 MHz, VDD = 2.0V(4)
FOSC = 10 MHz, VDD = 3.0V
FOSC = 20 MHz, VDD = 5.0V
FOSC = 32 kHz, VDD = 2.0V, WDT
disabled
D020
IPD
Power-down Current(5)
—
0.1
TBD
μA
VDD = 2.0V
D022
ΔIWDT WDT Current(5)
—
1.0
TBD
μA
VDD = 2.0V
Legend: TBD = To Be Determined.
* 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
guidance only and is not tested.
2: This is the limit to which VDD 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 IDD measurements in active operation mode are:
OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VSS, T0CKI = VDD,
MCLR = VDD;
WDT enabled/disabled as specified.
a) For standby current measurements, the conditions are the same, except that the device is in Sleep
mode.
4: Does not include current through REXT (in EXTRC mode only). The current through the resistor can be
estimated by the formula:
I = VDD/2REXT (mA) with REXT in kΩ.
5: The Power-down current in Sleep mode does not depend on the oscillator type. Power-down current is
measured with the part in Sleep mode, with all I/O pins in high-impedance state and tied to VDD or VSS.
DS41236C-page 70
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
DC CHARACTERISTICS: PIC12F508/509/16F505 (Industrial, Extended)
TABLE 10-1:
Standard Operating Conditions (unless otherwise specified)
Operating temperature -40°C ≤ TA ≤ +85°C (industrial)
-40°C ≤ TA ≤ +125°C (extended)
Operating voltage VDD range as described in DC specification
DC CHARACTERISTICS
Param
Sym
No.
VIL
Characteristic
Min
Typ†
Max
Units
Conditions
Input Low Voltage
I/O ports:
D030
with TTL buffer
D030A
D031
with Schmitt Trigger buffer
Vss
—
0.8V
V
For all 4.5 ≤ VDD ≤ 5.5V
Vss
—
0.15 VDD
V
Otherwise
Vss
—
0.15 VDD
V
D032
MCLR, T0CKI
Vss
—
0.15 VDD
V
D033
OSC1 (in EXTRC)
Vss
—
0.15 VDD
V
(Note1)
D033
OSC1 (in HS)
Vss
—
0.3 VDD
V
(Note1)
D033
OSC1 (in XT and LP)
Vss
—
0.3
V
(Note1)
VIH
Input High Voltage
I/O ports:
D040
with TTL buffer
D040A
D041
with Schmitt Trigger buffer
—
2.0
—
VDD
V
4.5 ≤ VDD ≤ 5.5V
0.25 VDD
+ 0.8 VDD
—
VDD
V
Otherwise
For entire VDD range
0.85 VDD
—
VDD
V
MCLR, T0CKI
0.85 VDD
—
VDD
V
D043
OSC1 (in EXTRC)
0.85 VDD
—
VDD
V
(Note1)
D043
OSC1 (in HS)
0.7 VDD
—
VDD
V
(Note1)
D043
OSC1 (in XT and LP)
1.6
—
VDD
V
TBD
250
TBD
μA
D042
IPUR GPIO weak pull-up current(4)
D070
IIL
VDD = 5V, VPIN = VSS
Input Leakage Current(2), (3)
D060
I/O ports
—
—
±1
μA
Vss ≤ VPIN ≤ VDD, Pin at high-impedance
D061
GP3/RB3/MCLRI(5)
—
—
± 30
μA
Vss ≤ VPIN ≤ VDD
D061A
GP3/RB3/MCLRI(6)
—
—
±5
μA
Vss ≤ VPIN ≤ VDD
D063
OSC1
—
—
±5
μA
Vss ≤ VPIN ≤ VDD, XT, HS and LP oscillator
configuration
D080
I/O ports/CLKOUT
—
—
0.6
V
IOL = 8.5 mA, VDD = 4.5V, -40°C to +85°C
—
—
0.6
V
IOL = 7.0 mA, VDD = 4.5V, -40°C to +125°C
—
—
0.6
V
IOL = 1.6 mA, VDD = 4.5V, -40°C to +85°C
—
—
0.6
V
IOL = 1.2 mA, VDD = 4.5V, -40°C to +125°C
VDD – 0.7
—
—
V
IOH = -3.0 mA, VDD = 4.5V, -40°C to +85°C
VDD – 0.7
—
—
V
IOH = -2.5 mA, VDD = 4.5V, -40°C to +125°C
VDD – 0.7
—
—
V
IOH = -1.3 mA, VDD = 4.5V, -40°C to +85°C
VDD – 0.7
—
—
V
IOH = -1.0 mA, VDD = 4.5V, -40°C to +125°C
OSC2 pin
—
—
15
pF
In XT, HS and LP modes when external clock is
used to drive OSC1.
All I/O pins and OSC2
—
—
50
pF
Output Low Voltage
D080A
D083
OSC2
D083A
Output High Voltage
I/O ports/CLKOUT(3)
D090
D090A
D092
OSC2
D092A
Capacitive Loading Specs on
Output Pins
D100
D101
Legend:
Note
†
1:
2:
3:
4:
5:
6:
TBD = To Be Determined.
Data in “Typ” column is at 5V, 25°C unless otherwise stated. These parameters are for design guidance only and are not tested.
In EXTRC oscillator configuration, the OSC1/CLKIN pin is a Schmitt Trigger input. It is not recommended that the PIC12F508/509/
16F505 be driven with external clock in RC mode.
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.
Negative current is defined as coming out of the pin.
Does not include GP3/RB3. For GP3/RB3 see parameters D061 and D061A.
This specification applies to GP3/RB3/MCLR configured as external MCLR and GP3/RB3/MCLR configured as input with internal pull-up
enabled.
This specification applies when GP3/RB3/MCLR is configured as an input with pull-up disabled. The leakage current of the MCLR circuit
is higher than the standard I/O logic.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 71
PIC12F508/509/16F505
TABLE 10-2:
VDD (Volts)
PULL-UP RESISTOR RANGES – PIC12F508/509/16F505
Temperature (°C)
Min
Typ
Max
Units
RB0/RB1/RB4
2.0
5.5
-40
TBD
TBD
TBD
Ω
25
TBD
TBD
TBD
Ω
85
TBD
TBD
TBD
Ω
125
TBD
TBD
TBD
Ω
-40
TBD
TBD
TBD
Ω
25
TBD
TBD
TBD
Ω
85
TBD
TBD
TBD
Ω
125
TBD
TBD
TBD
Ω
-40
TBD
TBD
TBD
Ω
25
TBD
TBD
TBD
Ω
85
TBD
TBD
TBD
Ω
RB3
2.0
5.5
125
TBD
TBD
TBD
Ω
-40
TBD
TBD
TBD
Ω
25
TBD
TBD
TBD
Ω
85
TBD
TBD
TBD
Ω
125
TBD
TBD
TBD
Ω
Legend: TBD = To Be determined.
* These parameters are characterized but not tested.
DS41236C-page 72
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
10.3
Timing Parameter Symbology and Load Conditions – PIC12F508/509/16F505
The timing parameter symbols have been created following one of the following formats:
1. TppS2ppS
2. TppS
T
F
Frequency
T Time
Lowercase subscripts (pp) and their meanings:
pp
2
to
mc
MCLR
ck
CLKOUT
osc
Oscillator
cy
Cycle time
os
OSC1
drt
Device Reset Timer
t0
T0CKI
io
I/O port
wdt
Watchdog Timer
Uppercase letters and their meanings:
S
F
Fall
P
Period
H
High
R
Rise
I
Invalid (high-impedance)
V
Valid
L
Low
Z
High-impedance
FIGURE 10-3:
LOAD CONDITIONS – PIC12F508/509/16F505
Legend:
CL
pin
CL = 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
VSS
FIGURE 10-4:
EXTERNAL CLOCK TIMING – PIC12F508/509/16F505
Q4
Q1
Q3
Q2
Q4
Q1
OSC1
1
3
3
4
4
2
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 73
PIC12F508/509/16F505
TABLE 10-3:
EXTERNAL CLOCK TIMING REQUIREMENTS – PIC12F508/509/16F505
AC CHARACTERISTICS
Standard Operating Conditions (unless otherwise specified)
Operating Temperature -40°C ≤ TA ≤ +85°C (industrial),
-40°C ≤ TA ≤ +125°C (extended)
Operating Voltage VDD range is described in Section 10.1 "DC
Characteristics"
Param
No.
Characteristic
Min
Typ(1)
External CLKIN Frequency(2)
DC
—
4
MHz XT Oscillator mode
DC
—
20
MHz HS Oscillator mode (PIC16F505
only)
DC
—
200
—
—
4
1A
Sym
FOSC
Oscillator Frequency(2)
1
TOSC
External CLKIN
Period(2)
Oscillator Period(2)
Max
Units
kHz
Conditions
LP Oscillator mode
MHz EXTRC Oscillator mode
0.1
—
4
MHz XT Oscillator mode
4
—
20
MHz HS Oscillator mode (PIC16F505
only)
—
—
200
kHz
LP Oscillator mode
250
—
—
ns
XT Oscillator mode
50
—
—
ns
HS Oscillator mode (PIC16F505
only)
5
—
—
μs
LP Oscillator mode
250
—
—
ns
EXTRC Oscillator mode
250
—
10,000
ns
XT Oscillator mode
50
—
250
ns
HS Oscillator mode (PIC16F505
only)
LP Oscillator mode
5
—
—
μs
2
TCY
Instruction Cycle Time
200
4/FOSC
—
ns
3
TosL,
TosH
Clock in (OSC1) Low or High
Time
50*
—
—
ns
XT Oscillator
2*
—
—
μs
LP Oscillator
10*
—
—
ns
HS Oscillator (PIC16F505 only)
TosR,
TosF
Clock in (OSC1) Rise or Fall
Time
—
—
25*
ns
XT Oscillator
—
—
50*
ns
LP Oscillator
—
—
15*
ns
HS Oscillator (PIC16F505 only)
4
*
Note 1:
2:
These parameters are characterized but not tested.
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.
All specified values are based on characterization data for that particular oscillator type under standard
operating 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.
DS41236C-page 74
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
TABLE 10-4:
CALIBRATED INTERNAL RC FREQUENCIES – PIC12F508/509/16F505
AC CHARACTERISTICS
Standard Operating Conditions (unless otherwise specified)
Operating Temperature -40°C ≤ TA ≤ +85°C (industrial),
-40°C ≤ TA ≤ +125°C (extended)
Operating Voltage VDD range is described in
Section 10.1 "DC Characteristics"
Param
No.
Freq
Min
Tolerance
F10
Sym
FOSC
Characteristic
Internal Calibrated
INTOSC Frequency(1)
Typ†
Max
Units
Conditions
± 1%
3.96
4.00
4.04
MHz VDD and Temperature
TBD
± 2%
3.92
4.00
4.08
MHz 2.5V ≤ VDD ≤ 5.5V
0°C ≤ TA ≤ +85°C
± 5%
3.80
4.00
4.20
MHz 2.0V ≤ VDD ≤ 5.5V
-40°C ≤ TA ≤ +85°C (Ind.)
-40°C ≤ TA ≤ +125°C (Ext.)
Legend: TBD = To Be Determined.
* These parameters are characterized but not tested.
† 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.
Note 1: To ensure these oscillator frequency tolerances, VDD and VSS must be capacitively decoupled as close to
the device as possible. 0.1 uF and 0.01 uF values in parallel are recommended.
FIGURE 10-5:
I/O TIMING – PIC12F508/509/16F505
Q1
Q4
Q2
Q3
OSC1
I/O Pin
(input)
17
I/O Pin
(output)
19
18
New Value
Old Value
20, 21
Note:
All tests must be done with specified capacitive loads (see data sheet) 50 pF on I/O pins and CLKOUT.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 75
PIC12F508/509/16F505
TABLE 10-5:
TIMING REQUIREMENTS – PIC12F508/509/16F505
Standard Operating Conditions (unless otherwise specified)
AC
Operating Temperature -40°C ≤ TA ≤ +85°C (industrial)
CHARACTERISTICS
-40°C ≤ TA ≤ +125°C (extended)
Operating Voltage VDD range is described in Section 10.1 "DC Characteristics"
Param
No.
Sym
17
TOSH2IOV
Characteristic
Min
Typ(1)
Max
Units
—
—
100*
ns
OSC1↑ (Q1 cycle) to Port Out Valid(2), (3)
(2)
18
TOSH2IOI
OSC1↑ (Q2 cycle) to Port Input Invalid (I/O in hold time)
TBD
—
—
ns
19
TIOV2OSH
Port Input Valid to OSC1↑ (I/O in setup time)
TBD
—
—
ns
—
10
25**
ns
—
10
25**
ns
TIOR
20
TIOF
21
Legend:
*
**
Note 1:
2:
3:
Port Output Rise Time
Port Output Fall Time
(3)
(3)
TBD = To Be Determined.
These parameters are characterized but not tested.
These parameters are design targets and are not tested.
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.
Measurements are taken in EXTRC mode.
See Figure 10-3 for loading conditions.
FIGURE 10-6:
RESET, WATCHDOG TIMER AND DEVICE RESET TIMER TIMING –
PIC12F508/509/16F505
VDD
MCLR
30
Internal
POR
32
32
32
DRT
Timeout(2)
Internal
Reset
Watchdog
Timer
Reset
31
34
34
I/O pin(1)
Note 1:
2:
I/O pins must be taken out of High-Impedance mode by enabling the output drivers in software.
Runs in MCLR or WDT Reset only in XT, LP and HS (PIC16F505) modes.
DS41236C-page 76
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
TABLE 10-6:
RESET, WATCHDOG TIMER AND DEVICE RESET TIMER – PIC12F508/509/16F505
Standard Operating Conditions (unless otherwise specified)
Operating Temperature -40°C ≤ TA ≤ +85°C (industrial)
-40°C ≤ TA ≤ +125°C (extended)
Operating Voltage VDD range is described in
Section 10.1 "DC Characteristics"
AC CHARACTERISTICS
Param
No.
Max
Units
Conditions
Characteristic
30
TMCL
MCLR Pulse Width (low)
2000*
—
—
ns
VDD = 5.0V
31
TWDT
Watchdog Timer Time-out Period
(no prescaler)
9*
9*
18*
18*
30*
40*
ms
ms
VDD = 5.0V (Industrial)
VDD = 5.0V (Extended)
32
TDRT
Device Reset Timer Period(2)
9*
9*
18*
18*
30*
40*
ms
ms
VDD = 5.0V (Industrial)
VDD = 5.0V (Extended)
34
TIOZ
I/O High-impedance from MCLR
low
—
—
2000*
ns
*
Note 1:
Min
Typ(1)
Sym
These parameters are characterized but not tested.
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.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 77
PIC12F508/509/16F505
FIGURE 10-7:
TIMER0 CLOCK TIMINGS – PIC12F508/509/16F505
T0CKI
40
41
42
TABLE 10-7:
TIMER0 CLOCK REQUIREMENTS – PIC12F508/509/16F505
Standard Operating Conditions (unless otherwise specified)
Operating Temperature -40°C ≤ TA ≤ +85°C (industrial)
-40°C ≤ TA ≤ +125°C (extended)
Operating Voltage VDD range is described in
Section 10.1 "DC Characteristics"
AC CHARACTERISTICS
Param
Sym
No.
40
41
42
*
Note 1:
Tt0H
Tt0L
Tt0P
Characteristic
T0CKI High Pulse
Width
T0CKI Low Pulse
Width
T0CKI Period
Min
No Prescaler
With Prescaler
No Prescaler
With Prescaler
Typ(1) Max Units
0.5 TCY + 20*
—
—
ns
10*
—
—
ns
0.5 TCY + 20*
—
—
ns
10*
—
—
ns
20 or TCY + 40* N
—
—
ns
Conditions
Whichever is greater.
N = Prescale Value
(1, 2, 4,..., 256)
These parameters are characterized but not tested.
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.
DS41236C-page 78
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
11.0
DC AND AC
CHARACTERISTICS GRAPHS
AND CHARTS
Graphs and charts are not available at this time.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 79
PIC12F508/509/16F505
NOTES:
DS41236C-page 80
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
12.0
PACKAGING INFORMATION
12.1
Package Marking Information
8-Lead PDIP
Example
12F508-I
/P e3 017
0410
XXXXXXXX
XXXXXNNN
YYWW
8-Lead SOIC (3.90 mm)
Example
XXXXXXXX
XXXXYYWW
NNN
12F509-I
/SN e3 0410
017
8-Lead MSOP
Example
12F509
0431017
XXXXXX
YWWNNN
8-Lead 2x3 DFN*
Example
XXX
YWW
NN
BE0
610
17
Legend: XX...X
Y
YY
WW
NNN
e3
*
Note:
*
Customer-specific information
Year code (last digit of calendar year)
Year code (last 2 digits of calendar year)
Week code (week of January 1 is week ‘01’)
Alphanumeric traceability code
Pb-free JEDEC designator for Matte Tin (Sn)
This package is Pb-free. The Pb-free JEDEC designator ( e3 )
can be found on the outer packaging for this package.
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 PIC® device marking consists of Microchip part number, year code, week code, and traceability
code. For PIC device 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.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 81
PIC12F508/509/16F505
12.1
Package Marking Information (Continued)
14-Lead PDIP (300 mil)
Example
XXXXXXXXXXXXXX
XXXXXXXXXXXXXX
YYWWNNN
PIC16F505
-I/PG e3 0215
0410017
Example
14-Lead SOIC (3.90 mm)
PIC16F505-E
/SLG0125
0431017
XXXXXXXXXXX
XXXXXXXXXXX
YYWWNNN
Example
14-Lead TSSOP (4.4 mm)
16F505-I
0431
017
XXXXXXXX
YYWW
NNN
DS41236C-page 82
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
8-Lead Plastic Dual In-Line (P) – 300 mil Body [PDIP]
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
N
NOTE 1
E1
1
3
2
D
E
A2
A
L
A1
c
e
eB
b1
b
Units
Dimension Limits
Number of Pins
INCHES
MIN
N
NOM
MAX
8
Pitch
e
Top to Seating Plane
A
–
–
.210
Molded Package Thickness
A2
.115
.130
.195
Base to Seating Plane
A1
.015
–
–
Shoulder to Shoulder Width
E
.290
.310
.325
Molded Package Width
E1
.240
.250
.280
Overall Length
D
.348
.365
.400
Tip to Seating Plane
L
.115
.130
.150
Lead Thickness
c
.008
.010
.015
b1
.040
.060
.070
b
.014
.018
.022
eB
–
–
Upper Lead Width
Lower Lead Width
Overall Row Spacing §
.100 BSC
.430
Notes:
1. Pin 1 visual index feature may vary, but must be located with the hatched area.
2. § Significant Characteristic.
3. Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed .010" per side.
4. Dimensioning and tolerancing per ASME Y14.5M.
BSC: Basic Dimension. Theoretically exact value shown without tolerances.
Microchip Technology Drawing C04-018B
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 83
PIC12F508/509/16F505
8-Lead Plastic Small Outline (SN) – Narrow, 3.90 mm Body [SOIC]
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
D
e
N
E
E1
NOTE 1
1
2
3
α
h
b
h
A2
A
c
φ
L
A1
L1
Units
Dimension Limits
Number of Pins
β
MILLIMETERS
MIN
N
NOM
MAX
8
Pitch
e
Overall Height
A
–
1.27 BSC
–
Molded Package Thickness
A2
1.25
–
–
Standoff §
A1
0.10
–
0.25
Overall Width
E
Molded Package Width
E1
3.90 BSC
Overall Length
D
4.90 BSC
1.75
6.00 BSC
Chamfer (optional)
h
0.25
–
0.50
Foot Length
L
0.40
–
1.27
Footprint
L1
1.04 REF
Foot Angle
φ
0°
–
8°
Lead Thickness
c
0.17
–
0.25
Lead Width
b
0.31
–
0.51
Mold Draft Angle Top
α
5°
–
15°
Mold Draft Angle Bottom
β
5°
–
15°
Notes:
1. Pin 1 visual index feature may vary, but must be located within the hatched area.
2. § Significant Characteristic.
3. Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed 0.15 mm per side.
4. Dimensioning and tolerancing per ASME Y14.5M.
BSC: Basic Dimension. Theoretically exact value shown without tolerances.
REF: Reference Dimension, usually without tolerance, for information purposes only.
Microchip Technology Drawing C04-057B
DS41236C-page 84
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
8-Lead Plastic Micro Small Outline Package (MS) [MSOP]
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
D
N
E
E1
NOTE 1
1
2
e
b
A2
A
c
φ
L
L1
A1
Units
Dimension Limits
Number of Pins
MILLIMETERS
MIN
N
NOM
MAX
8
Pitch
e
Overall Height
A
–
0.65 BSC
–
Molded Package Thickness
A2
0.75
0.85
0.95
Standoff
A1
0.00
–
0.15
Overall Width
E
Molded Package Width
E1
3.00 BSC
Overall Length
D
3.00 BSC
Foot Length
L
Footprint
L1
1.10
4.90 BSC
0.40
0.60
0.80
0.95 REF
Foot Angle
φ
0°
–
8°
Lead Thickness
c
0.08
–
0.23
Lead Width
b
0.22
–
0.40
Notes:
1. Pin 1 visual index feature may vary, but must be located within the hatched area.
2. Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed 0.15 mm per side.
3. Dimensioning and tolerancing per ASME Y14.5M.
BSC: Basic Dimension. Theoretically exact value shown without tolerances.
REF: Reference Dimension, usually without tolerance, for information purposes only.
Microchip Technology Drawing C04-111B
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 85
PIC12F508/509/16F505
8-Lead Plastic Dual Flat, No Lead Package (MC) – 2x3x0.9 mm Body [DFN]
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
D
e
b
N
N
L
K
E2
E
EXPOSED PAD
NOTE 1
2
1
NOTE 1
1
2
D2
BOTTOM VIEW
TOP VIEW
A
A3
A1
NOTE 2
Units
Dimension Limits
Number of Pins
MILLIMETERS
MIN
N
NOM
MAX
8
Pitch
e
Overall Height
A
0.80
0.90
1.00
Standoff
A1
0.00
0.02
0.05
Contact Thickness
A3
0.20 REF
Overall Length
D
2.00 BSC
Overall Width
E
Exposed Pad Length
D2
1.30
–
Exposed Pad Width
E2
1.50
–
1.90
b
0.18
0.25
0.30
Contact Length
L
0.30
0.40
0.50
Contact-to-Exposed Pad
K
0.20
–
–
Contact Width
0.50 BSC
3.00 BSC
1.75
Notes:
1. Pin 1 visual index feature may vary, but must be located within the hatched area.
2. Package may have one or more exposed tie bars at ends.
3. Package is saw singulated.
4. Dimensioning and tolerancing per ASME Y14.5M.
BSC: Basic Dimension. Theoretically exact value shown without tolerances.
REF: Reference Dimension, usually without tolerance, for information purposes only.
Microchip Technology Drawing C04-123B
DS41236C-page 86
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
14-Lead Plastic Dual In-Line (P) – 300 mil Body [PDIP]
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
N
NOTE 1
E1
1
3
2
D
E
A2
A
L
A1
c
b1
b
e
eB
Units
Dimension Limits
Number of Pins
INCHES
MIN
N
NOM
MAX
14
Pitch
e
Top to Seating Plane
A
–
–
.210
Molded Package Thickness
A2
.115
.130
.195
Base to Seating Plane
A1
.015
–
–
Shoulder to Shoulder Width
E
.290
.310
.325
Molded Package Width
E1
.240
.250
.280
Overall Length
D
.735
.750
.775
Tip to Seating Plane
L
.115
.130
.150
Lead Thickness
c
.008
.010
.015
b1
.045
.060
.070
b
.014
.018
.022
eB
–
–
Upper Lead Width
Lower Lead Width
Overall Row Spacing §
.100 BSC
.430
Notes:
1. Pin 1 visual index feature may vary, but must be located with the hatched area.
2. § Significant Characteristic.
3. Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed .010" per side.
4. Dimensioning and tolerancing per ASME Y14.5M.
BSC: Basic Dimension. Theoretically exact value shown without tolerances.
Microchip Technology Drawing C04-005B
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 87
PIC12F508/509/16F505
14-Lead Plastic Small Outline (SL) – Narrow, 3.90 mm Body [SOIC]
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
D
N
E
E1
NOTE 1
1
2
3
e
h
b
A
c
φ
A2
L
A1
β
L1
Units
Dimension Limits
Number of Pins
α
h
MILLIMETERS
MIN
N
NOM
MAX
14
Pitch
e
Overall Height
A
–
1.27 BSC
–
Molded Package Thickness
A2
1.25
–
–
Standoff §
A1
0.10
–
0.25
Overall Width
E
Molded Package Width
E1
3.90 BSC
Overall Length
D
8.65 BSC
1.75
6.00 BSC
Chamfer (optional)
h
0.25
–
0.50
Foot Length
L
0.40
–
1.27
Footprint
L1
1.04 REF
Foot Angle
φ
0°
–
8°
Lead Thickness
c
0.17
–
0.25
Lead Width
b
0.31
–
0.51
Mold Draft Angle Top
α
5°
–
15°
Mold Draft Angle Bottom
β
5°
–
15°
Notes:
1. Pin 1 visual index feature may vary, but must be located within the hatched area.
2. § Significant Characteristic.
3. Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed 0.15 mm per side.
4. Dimensioning and tolerancing per ASME Y14.5M.
BSC: Basic Dimension. Theoretically exact value shown without tolerances.
REF: Reference Dimension, usually without tolerance, for information purposes only.
Microchip Technology Drawing C04-065B
DS41236C-page 88
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
14-Lead Plastic Thin Shrink Small Outline (ST) – 4.4 mm Body [TSSOP]
Note:
For the most current package drawings, please see the Microchip Packaging Specification located at
http://www.microchip.com/packaging
D
N
E
E1
NOTE 1
1 2
e
b
A2
A
c
A1
φ
Units
Dimension Limits
Number of Pins
L
L1
MILLIMETERS
MIN
N
NOM
MAX
14
Pitch
e
Overall Height
A
–
0.65 BSC
–
Molded Package Thickness
A2
0.80
1.00
1.05
Standoff
A1
0.05
–
0.15
1.20
Overall Width
E
Molded Package Width
E1
4.30
6.40 BSC
4.40
Molded Package Length
D
4.90
5.00
5.10
Foot Length
L
0.45
0.60
0.75
Footprint
L1
4.50
1.00 REF
Foot Angle
φ
0°
–
8°
Lead Thickness
c
0.09
–
0.20
Lead Width
b
0.19
–
0.30
Notes:
1. Pin 1 visual index feature may vary, but must be located within the hatched area.
2. Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed 0.15 mm per side.
3. Dimensioning and tolerancing per ASME Y14.5M.
BSC: Basic Dimension. Theoretically exact value shown without tolerances.
REF: Reference Dimension, usually without tolerance, for information purposes only.
Microchip Technology Drawing C04-087B
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 89
PIC12F508/509/16F505
APPENDIX A:
REVISION HISTORY
Revision A (April 2004)
Original
devices
data
sheet
for
PIC12F508/509/16F505
Revision B (June 2005)
Update packages
Revision C (03/2007)
Revised Table 3-2 Legend; Revised Table 3-3 RB3 and
Legend; Revised Table 10-4 F10; Replaced Package
Drawings (Rev. AN); Added DFN package; Replaced
Development Support Section; Revised Product ID
System.
DS41236C-page 90
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
NOTES:
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 91
PIC12F508/509/16F505
INDEX
A
ALU ....................................................................................... 9
Assembler
MPASM Assembler ..................................................... 64
B
Block Diagram
On-Chip Reset Circuit ................................................. 47
Timer0 ......................................................................... 33
TMR0/WDT Prescaler ................................................. 37
Watchdog Timer.......................................................... 50
Brown-Out Protection Circuit............................................... 51
C
C Compilers
MPLAB C18 ................................................................ 64
MPLAB C30 ................................................................ 64
Carry ..................................................................................... 9
Clocking Scheme ................................................................ 14
Code Protection ............................................................ 39, 52
Configuration Bits................................................................ 39
Configuration Word ............................................................. 40
Customer Change Notification Service ............................... 93
Customer Notification Service............................................. 93
Customer Support ............................................................... 93
D
DC and AC Characteristics ................................................. 79
Development Support ......................................................... 63
Digit Carry ............................................................................. 9
MPLAB ICE 4000 High-Performance Universal
In-Circuit Emulator ...................................................... 65
MPLAB Integrated Development Environment Software.... 63
MPLAB PM3 Device Programmer ...................................... 65
MPLINK Object Linker/MPLIB Object Librarian .................. 64
O
Option Register................................................................... 22
OSC selection..................................................................... 39
OSCCAL Register............................................................... 24
Oscillator Configurations..................................................... 41
Oscillator Types
HS............................................................................... 41
LP ............................................................................... 41
RC .............................................................................. 41
XT ............................................................................... 41
P
PIC12F508/509/16F505 Device Varieties ............................ 7
PICSTART Plus Development Programmer....................... 66
POR
Device Reset Timer (DRT) ................................... 39, 49
PD............................................................................... 51
Power-on Reset (POR)............................................... 39
TO............................................................................... 51
PORTB ............................................................................... 29
Power-down Mode.............................................................. 52
Prescaler............................................................................. 36
Program Counter ................................................................ 25
Q
E
Q cycles .............................................................................. 14
Errata .................................................................................... 3
R
F
RC Oscillator....................................................................... 42
Reader Response............................................................... 94
Read-Modify-Write.............................................................. 31
Register File Map
PIC12F508 ................................................................. 17
PIC12F509 ................................................................. 17
PIC16F505 ................................................................. 17
Registers
Special Function ......................................................... 18
Reset .................................................................................. 39
Reset on Brown-Out ........................................................... 51
Family of Devices
PIC12F508/509/PIC16F505.......................................... 5
FSR ..................................................................................... 26
I
I/O Interfacing...................................................................... 29
I/O Ports .............................................................................. 29
I/O Programming Considerations........................................ 31
ID Locations .................................................................. 39, 52
INDF.................................................................................... 26
Indirect Data Addressing..................................................... 26
Instruction Cycle.................................................................. 14
Instruction Flow/Pipelining .................................................. 14
Instruction Set Summary..................................................... 56
Internet Address.................................................................. 93
S
Loading of PC ..................................................................... 25
Sleep............................................................................. 39, 52
Software Simulator (MPLAB SIM) ...................................... 64
Special Features of the CPU .............................................. 39
Special Function Registers ................................................. 18
Stack................................................................................... 25
Status Register ............................................................... 9, 20
M
T
Memory Organization.......................................................... 15
Data Memory .............................................................. 16
Program Memory (PIC12F508/509)............................ 15
Program Memory (PIC16F505)................................... 16
Microchip Internet Web Site ................................................ 93
MPLAB ASM30 Assembler, Linker, Librarian ..................... 64
MPLAB ICD 2 In-Circuit Debugger...................................... 65
MPLAB ICE 2000 High-Performance Universal
In-Circuit Emulator ...................................................... 65
Timer0
Timer0 ........................................................................ 33
Timer0 (TMR0) Module............................................... 33
TMR0 with External Clock .......................................... 35
Timing Diagrams and Specifications .................................. 73
Timing Parameter Symbology and Load Conditions .......... 73
TRIS Registers ................................................................... 29
L
DS41236C-page 92
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
W
Wake-up from Sleep ........................................................... 52
Watchdog Timer (WDT) ................................................ 39, 49
Period.......................................................................... 49
Programming Considerations ..................................... 49
WWW Address.................................................................... 93
WWW, On-Line Support ....................................................... 3
Z
Zero bit .................................................................................. 9
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 93
PIC12F508/509/16F505
NOTES:
DS41236C-page 94
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
THE MICROCHIP WEB SITE
CUSTOMER SUPPORT
Microchip provides online support via our WWW site at
www.microchip.com. This web site is used as a means
to make files and information easily available to
customers. Accessible by using your favorite Internet
browser, the web site contains the following
information:
Users of Microchip products can receive assistance
through several channels:
• Product Support – Data sheets and errata,
application notes and sample programs, design
resources, user’s guides and hardware support
documents, latest software releases and archived
software
• General Technical Support – Frequently Asked
Questions (FAQ), technical support requests,
online discussion groups, Microchip consultant
program member listing
• Business of Microchip – Product selector and
ordering guides, latest Microchip press releases,
listing of seminars and events, listings of
Microchip sales offices, distributors and factory
representatives
•
•
•
•
•
Distributor or Representative
Local Sales Office
Field Application Engineer (FAE)
Technical Support
Development Systems Information Line
Customers
should
contact
their
distributor,
representative or field application engineer (FAE) for
support. Local sales offices are also available to help
customers. A listing of sales offices and locations is
included in the back of this document.
Technical support is available through the web site
at: http://support.microchip.com
CUSTOMER CHANGE NOTIFICATION
SERVICE
Microchip’s customer notification service helps keep
customers current on Microchip products. Subscribers
will receive e-mail notification whenever there are
changes, updates, revisions or errata related to a
specified product family or development tool of interest.
To register, access the Microchip web site at
www.microchip.com, click on Customer Change
Notification and follow the registration instructions.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 95
PIC12F508/509/16F505
READER RESPONSE
It is our intention to provide you with the best documentation possible to ensure successful use of your Microchip product. If you wish to provide your comments on organization, clarity, subject matter, and ways in which our documentation
can better serve you, please FAX your comments to the Technical Publications Manager at (480) 792-4150.
Please list the following information, and use this outline to provide us with your comments about this document.
To:
Technical Publications Manager
RE:
Reader Response
Total Pages Sent ________
From: Name
Company
Address
City / State / ZIP / Country
Telephone: (_______) _________ - _________
FAX: (______) _________ - _________
Application (optional):
Would you like a reply?
Y
Device: PIC12F508/509/16F505
N
Literature Number: DS41236C
Questions:
1. What are the best features of this document?
2. How does this document meet your hardware and software development needs?
3. Do you find the organization of this document easy to follow? If not, why?
4. What additions to the document do you think would enhance the structure and subject?
5. What deletions from the document could be made without affecting the overall usefulness?
6. Is there any incorrect or misleading information (what and where)?
7. How would you improve this document?
DS41236C-page 96
Preliminary
© 2007 Microchip Technology Inc.
PIC12F508/509/16F505
PRODUCT IDENTIFICATION SYSTEM
To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.
PART NO.
X
/XX
XXX
Device
Temperature
Range
Package
Pattern
Examples:
a)
b)
Device:
PIC16F505
PIC12F508
PIC12F509
PIC16F505T(1)
PIC12F508T(1, 2)
PIC12F509T(1, 2)
Temperature
Range:
I
E
Package:
MC
MS
P
SL
SN
ST
Pattern:
Note:
=
=
c)
PIC12F508-E/P 301 = Extended Temp., PDIP
package, QTP pattern #301
PIC12F508-I/SN = Industrial Temp., SOIC
package
PIC12F508T-E/P = Extended Temp., PDIP
package, Tape and Reel
-40°C to +85°C (Industrial)
-40°C to +125°C (Extended)
=
=
=
=
=
=
8L DFN 2x3 (DUAL Flatpack No-Leads)(3)
Micro-Small Outline Package (MSOP)(3, 4)
Plastic (PDIP)(4)
14L Small Outline, 3.90 mm (SOIC)(4)
8L Small Outline, 3.90 mm Narrow (SOIC)(4)
Thin Shrink Small Outline (TSSOP)(4)
Note 1:
2:
3:
4:
Special Requirements
T
= in tape and reel SOIC and TSSOP
packages only
T = in tape and reel SOIC and MSOP
packages only.
PIC12F508/PIC12F509 only.
Pb-free.
Tape and Reel available for only the following packages: SOIC, MSOP
and TSSOP.
© 2007 Microchip Technology Inc.
Preliminary
DS41236C-page 97
WORLDWIDE SALES AND SERVICE
AMERICAS
ASIA/PACIFIC
ASIA/PACIFIC
EUROPE
Corporate Office
2355 West Chandler Blvd.
Chandler, AZ 85224-6199
Tel: 480-792-7200
Fax: 480-792-7277
Technical Support:
http://support.microchip.com
Web Address:
www.microchip.com
Asia Pacific Office
Suites 3707-14, 37th Floor
Tower 6, The Gateway
Habour City, Kowloon
Hong Kong
Tel: 852-2401-1200
Fax: 852-2401-3431
India - Bangalore
Tel: 91-80-4182-8400
Fax: 91-80-4182-8422
India - New Delhi
Tel: 91-11-4160-8631
Fax: 91-11-4160-8632
Austria - Wels
Tel: 43-7242-2244-39
Fax: 43-7242-2244-393
Denmark - Copenhagen
Tel: 45-4450-2828
Fax: 45-4485-2829
India - Pune
Tel: 91-20-2566-1512
Fax: 91-20-2566-1513
France - Paris
Tel: 33-1-69-53-63-20
Fax: 33-1-69-30-90-79
Japan - Yokohama
Tel: 81-45-471- 6166
Fax: 81-45-471-6122
Germany - Munich
Tel: 49-89-627-144-0
Fax: 49-89-627-144-44
Atlanta
Duluth, GA
Tel: 678-957-9614
Fax: 678-957-1455
Boston
Westborough, MA
Tel: 774-760-0087
Fax: 774-760-0088
Chicago
Itasca, IL
Tel: 630-285-0071
Fax: 630-285-0075
Dallas
Addison, TX
Tel: 972-818-7423
Fax: 972-818-2924
Detroit
Farmington Hills, MI
Tel: 248-538-2250
Fax: 248-538-2260
Kokomo
Kokomo, IN
Tel: 765-864-8360
Fax: 765-864-8387
Los Angeles
Mission Viejo, CA
Tel: 949-462-9523
Fax: 949-462-9608
Santa Clara
Santa Clara, CA
Tel: 408-961-6444
Fax: 408-961-6445
Toronto
Mississauga, Ontario,
Canada
Tel: 905-673-0699
Fax: 905-673-6509
Australia - Sydney
Tel: 61-2-9868-6733
Fax: 61-2-9868-6755
China - Beijing
Tel: 86-10-8528-2100
Fax: 86-10-8528-2104
Korea - Gumi
Tel: 82-54-473-4301
Fax: 82-54-473-4302
China - Chengdu
Tel: 86-28-8665-5511
Fax: 86-28-8665-7889
China - Fuzhou
Tel: 86-591-8750-3506
Fax: 86-591-8750-3521
Korea - Seoul
Tel: 82-2-554-7200
Fax: 82-2-558-5932 or
82-2-558-5934
China - Hong Kong SAR
Tel: 852-2401-1200
Fax: 852-2401-3431
Malaysia - Penang
Tel: 60-4-646-8870
Fax: 60-4-646-5086
China - Qingdao
Tel: 86-532-8502-7355
Fax: 86-532-8502-7205
Philippines - Manila
Tel: 63-2-634-9065
Fax: 63-2-634-9069
China - Shanghai
Tel: 86-21-5407-5533
Fax: 86-21-5407-5066
Singapore
Tel: 65-6334-8870
Fax: 65-6334-8850
China - Shenyang
Tel: 86-24-2334-2829
Fax: 86-24-2334-2393
Taiwan - Hsin Chu
Tel: 886-3-572-9526
Fax: 886-3-572-6459
China - Shenzhen
Tel: 86-755-8203-2660
Fax: 86-755-8203-1760
Taiwan - Kaohsiung
Tel: 886-7-536-4818
Fax: 886-7-536-4803
China - Shunde
Tel: 86-757-2839-5507
Fax: 86-757-2839-5571
Taiwan - Taipei
Tel: 886-2-2500-6610
Fax: 886-2-2508-0102
China - Wuhan
Tel: 86-27-5980-5300
Fax: 86-27-5980-5118
Thailand - Bangkok
Tel: 66-2-694-1351
Fax: 66-2-694-1350
Italy - Milan
Tel: 39-0331-742611
Fax: 39-0331-466781
Netherlands - Drunen
Tel: 31-416-690399
Fax: 31-416-690340
Spain - Madrid
Tel: 34-91-708-08-90
Fax: 34-91-708-08-91
UK - Wokingham
Tel: 44-118-921-5869
Fax: 44-118-921-5820
China - Xian
Tel: 86-29-8833-7250
Fax: 86-29-8833-7256
12/08/06
DS41236C-page 98
Preliminary
© 2007 Microchip Technology Inc.