PIC16F628-20P Datasheet, PDF (109/170 Pages) Microchip Technology – FLASH-Based 8-Bit CMOS Microcontroller

PIC16F62X
15.0 INSTRUCTION SET SUMMARY
Each PIC16F62X 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 PIC16F62X instruction
set summary in Table 15-2 lists byte-oriented, bit-
oriented, and literal and control operations. Table 15-1
shows the opcode field descriptions.
For byte-oriented instructions, 'f' represents a file
register designator and 'd' represents a destination
designator. The file register designator 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 number of the bit affected
by the operation, while 'f' represents the number of the
file in which the bit is located.
For literal and control operations, 'k' represents an
eight or eleven bit constant or literal value.
TABLE 15-1: OPCODE FIELD
DESCRIPTIONS
Field
Description
f
W
b
k
x
d
label
TOS
PC
PCLA
TH
GIE
WDT
TO
PD
dest
[]
()
→
<>
∈
italics
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 W,
d = 1: store result in file register f.
Default is d = 1
Label name
Top of Stack
Program Counter
Program Counter High Latch
Global Interrupt Enable bit
Watchdog Timer/Counter
Timeout bit
Power-down bit
Destination either the W register or the specified regis-
ter file location
Options
Contents
Assigned to
Register bit field
In the set of
User defined term (font is courier)
The instruction set is highly orthogonal and is grouped
into three basic categories:
• Byte-oriented operations
• Bit-oriented operations
• Literal and control operations
All instructions are executed within one 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 with the second cycle executed as a
NOP. 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.
Table 15-2 lists the instructions recognized by the
MPASM™ assembler.
Figure 15-1 shows the three general formats that the
instructions can have.
Note 1: Any unused opcode is reserved. Use of
any reserved opcode may cause unex-
pected operation.
2: To maintain upward compatibility with
future PICmicro^® products, do not use the
OPTION and TRIS instructions.
All examples use the following format to represent a
hexadecimal number:
0xhh
where h signifies a hexadecimal digit.
FIGURE 15-1:
GENERAL FORMAT FOR
INSTRUCTIONS
Byte-oriented file register operations
13
8 76
0
OPCODE
d
f (FILE #)
d = 0 for destination W
d = 1 for destination f
f = 7-bit file register address
Bit-oriented file register operations
13
10 9
76
OPCODE
b (BIT #)
0
f (FILE #)
b = 3-bit bit address
f = 7-bit file register address
Literal and control operations
General
13
87
OPCODE
k = 8-bit immediate value
0
k (literal)
CALL and GOTO instructions only
13
11 10
0
OPCODE
k (literal)
k = 11-bit immediate value
 2003 Microchip Technology Inc.
Preliminary
DS40300C-page 107