PIC12F635-I/MD Microchip Technology, PIC12F635-I/MD Datasheet - Page 151

• Manufacturer Part Number: PIC12F635-I/MD
• Description: IC PIC MCU FLASH 1KX14 8DFN
• Manufacturer: Microchip Technology
• Series: PIC® 12Fr

Specifications of PIC12F635-I/MD

• Core Size: 8-Bit
• Program Memory Size: 1.75KB (1K x 14)
• Core Processor: PIC
• Speed: 20MHz
• Peripherals: Brown-out Detect/Reset, POR, WDT
• Number Of I /o: 5
• Program Memory Type: FLASH
• Eeprom Size: 128 x 8
• Ram Size: 64 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 8-DFN
• Controller Family/series: PIC12
• No. Of I/o's: 6
• Eeprom Memory Size: 128Byte
• Ram Memory Size: 64Byte
• Cpu Speed: 20MHz
• No. Of Timers: 2
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: AC164326 - MODULA SKT PM3 20QFNXLT08DFN2 - SOCKET TRANSITION ICE 14DIP/8DFNAC162057 - MPLAB ICD 2 HEADER 14DIPXLT08DFN - SOCKET TRANSITION ICE 8DFN
• Data Converters: -
• Connectivity: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

13.0
The PIC12F635/PIC16F636/639 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 14-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 13-1, while the various opcode
fields are summarized in Table 13-1.
Table 13-2 lists the instructions recognized by the
MPASM
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 zero, the result is
placed in the W register. If ‘d’ is one, 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 bit affected by the
operation, while ‘f’ represents the address of the file in
which the bit is located.
For literal and control operations, ‘k’ represents an
8-bit or 11-bit constant, or literal value.
One instruction cycle consists of four oscillator periods;
for an oscillator frequency of 4 MHz, this gives a
nominal instruction execution time of 1 s. 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. When
this occurs, the execution takes two instruction cycles,
with the second cycle executed as a NOP.
All instruction examples use the format ‘0xhh’ to
represent a hexadecimal number, where ‘h’ signifies a
hexadecimal digit.
13.1
Any instruction that specifies a file register as part of
the instruction performs a Read-Modify-Write (R-M-W)
operation. The register is read, the data is modified,
and the result is stored according to either the
instruction, or the destination designator ‘d’. A read
operation is performed on a register even if the
instruction writes to that register.
For example, a CLRF
PORTA, clear all the data bits, then write the result back
to PORTA. This example would have the unintended
consequence of clearing the condition that set the RAIF
flag.
© 2007 Microchip Technology Inc.
TM
INSTRUCTION SET SUMMARY
Read-Modify-Write Operations
assembler.
PORTA instruction will read
PIC12F635/PIC16F636/639
TABLE 13-1:
FIGURE 13-1:
Field
PC
TO
DC
PD
W
C
b
d
Z
k
x
f
Byte-oriented file register operations
Bit-oriented file register operations
Literal and control operations
General
CALL and GOTO instructions only
13
13
13
13
Register file address (0x00 to 0x7F)
Working register (accumulator)
Bit address within an 8-bit file register
Literal field, constant data or label
Don’t care location (= 0 or 1).
The assembler will generate code with x = 0.
It is the recommended form of use for
compatibility with all Microchip software tools.
Destination select; d = 0: store result in
d = 1: store result in file register f.
Default is d = 1.
Program Counter
Time-out bit
Carry bit
Digit carry bit
Zero bit
Power-down bit
OPCODE
d = 0 for destination W
d = 1 for destination f
f = 7-bit file register address
b = 3-bit bit address
f = 7-bit file register address
k = 8-bit immediate value
k = 11-bit immediate value
OPCODE
OPCODE
OPCODE
11
OPCODE FIELD
DESCRIPTIONS
10
10 9
GENERAL FORMAT FOR
INSTRUCTIONS
8
Description
b (BIT #)
7
d
8
6
7
7 6
k (literal)
DS41232D-page 149
f (FILE #)
k (literal)
f (FILE #)
W
0
0
0
0
,