The document provides a comprehensive overview of the instruction set for a RISC microcontroller, detailing 35 specific instructions categorized into data processing operations, arithmetic and logic operations, bit operations, and program control operations. Each instruction is described with its syntax, function, operand range, operation, number of words, number of cycles, and relevant flags. The document also includes examples and explanations of addressing modes and other relevant microcontroller functionalities.

1. Instruction Sets – PIC
Done by,
Priyanga KR,
Assistant Professor,
Department of ECE,
Avinashilingam Institute.

2. • Complete set: 35 instructions.
• MC Architecture: RISC microcontroller.
Instruction Types:
1. Data Processing Operations:
– Copy data between registers.
– Manipulate data in a single register.
2. Arithmetic and Logic operations:
3. Bit Operation:
4. Program Sequence Control Operations:
– Unconditional Jump.
– Conditional Jump.
– Call.
– Control.

3. Status Register

4. Addressing modes
• The way by which the address of the operand
are specified in the instruction.
• Types
• Direct Addressing Modes
• Indirect Addressing Modes
• Immediate Addressing Modes

5. Direct Addressing Modes

7. Immediate Addressing modes
MOVLW 43h
Goto loop

8. Word list
• f - any memory location in a microcontroller
• W - work register
• b - bit position in 'f' register
• d - destination bit
• label group of eight characters which marks the
beginning of a part of the program
• TOS - top of stack
• [ ] - option
• < > - bit position inside register

9. Data Processing Operations
• To move or change the value (bits) from one
location to another

10. 1. MOVLW
Syntax: Label MOVLW k
Description: 8 bit constant
is written in W reg.
Operation: k to (W)
Operand: 0 < k < 255
No. of words: 1
No. cycles: 1
Flags: Nil
2. MOVWF
Syntax: Label MOVWF f
Description: Content of W
is copied into f register
(flag register).
Operation: W to (f) (W
register to Flag register)
Operand: 0 < f < 127
No. of words: 1
No. cycles: 1
Flags: Nil

11. 3. MOVF
•Syntax: Label MOVF f, d
•Description: Content of f
is copied into destination.
If d = 0, the destination is
W register
If d = 1, the destination is f
register
•Operation: F to (D)
•Operand: 0 < k < 127
•No. of words: 1
•No. cycles: 1
•Flags: Z
4. CLRW
•Syntax: Label CLRW
•Description: Zero is
copied into W register
Z flag in status register is
set to one
•Operation: 0 to (W)
•Operand: nil
•No. of words: 1
•No. cycles: 1
•Flags: Z

12. 5. SWAPF
•Syntax: Label SWAPF f, d
•Description: Upper,
Lower nibbles are
exchanged
If d = 0, the destination is
W register & If d = 1, the
destination is f register
•Operation: f (0:3) to
d(4:7) and f(4:7) to d(0:3)
•Operand: 0 < f < 127
•No. of words: 1
•No. cycles: 1
•Flags: —
6. CLRF f
Syntax: Label CLRF f
Description: Zero is copied
into f register
Z flag in status register is
set to one
Operation: 0 to (f)
Operand: nil
No. of words: 1
No. cycles: 1
Flags: Z

13. Arithmetic and Logic operations
• The arithmetic operations are addition (ADD),
subtraction (SUB), multiplication (MUL),
division (DIV) and logical operations are AND,
OR, NOT, XOR, and so on.

14. 1. ADDLW
Syntax: Label ADDLW k
Description: Given
constant is added with W
reg.
Operation: (w) + k to w
Operand: 0 < k < 255
No. of words: 1
No. cycles: 1
Flags: C, DC, Z
2) ADDWF
Syntax: Label ADDWF f, d
Description: Add W reg.
content with f register
Operation:
(w) + (f) to w if d = 0 and
(w) + (f) to f if d = 1
Operand: 0 < f < 127
No. of words: 1
No. cycles: 1
Flags: C, DC, Z

15. 3) SUBLW
•Syntax: Label SUBLW k
•Description: W reg.
content is subtracted from
k
•Operation: k – (w) to w
•Operand: 0 < k < 255
•No. of words: 1
•No. cycles: 1
•Flags: C, DC, Z
4) SUBWF
•Syntax: Label SUBWF f
•Description: W reg.
content is subtracted from
f
•Operation:
f – (w) to w if d = 0 and
f – (w) to f if d = 1
•Operand: 0 < f < 127
•No. of words: 1
•No. cycles: 1
•Flags: C, DC, Z

16. 5) ANDLW
•Syntax: Label ANDLW k
•Description: Given
constant is .and. with W
reg.
•Operation: (w) .and. k to
w
•Operand: 0 < k < 255
•No. of words: 1
•No. cycles: 1
•Flags: Z
6) IORLW
•Syntax: Label IORLW k
•Description: Given
constant is .or. with W
reg.
•Operation: (w) .or. k to w
•Operand: 0 < k < 255
•No. of words: 1
•No. cycles: 1
•Flags: Z

17. 7) IORWF
Logic OR the W reg. with f
•Syntax: Label IORWF f, d
•Description: W reg. is .or.
with f reg.
•Operation:
(w) .and. f to w, if d = 0
(w) .and. f to f, if d = 1
•Operand: 0 < f < 127
•No. of words: 1
•No. cycles: 1
•Flags: Z
8 ) XORLW
•Syntax: Label XORLW k
•Description: Given
constant is .XOR. with W
reg.
•Operation: (w) .xor. k to
w
•Operand: 0 < k < 255
•No. of words: 1
•No. cycles: 1
•Flags: Z

18. 9) XORWF
•Syntax: Label XORWF f, d
•Description: W reg. is
.xor. with f reg.
•Operation:
(w) .and. f to w, if d = 0
(w) .and. f to f, if d = 1
•Operand: 0 < f < 127
•No. of words: 1
•No. cycles: 1
•Flags: Z
10) INCF
•Syntax: Label INCF f, d
•Description: Increment
the content of f register
•Operation:
(f) + 1 to w, if d = 0 and
(f) + 1 to f, if d = 1
•Operand: 0 < f < 127
•No. of words: 1
•No. cycles: 1
•Flags: Z

19. 11) DECF
•Syntax: Label DECF f, d
•Description: Decrement
the content of f register
•Operation:
(f) – 1 to w, if d = 0 and
(f) – 1 to f, if d = 1
•Operand: 0 < f < 127
•No. of words: 1
•No. cycles: 1
•Flags: Z
12) RLF
•Syntax: Label RLF f, d
•Description: Rotate f
content left through Carry
•Operation:
Result to w, if d = 0 and
Result to f, if d = 1
•Operand: 0 < f < 127
•No. of words: 1
•No. cycles: 1
•Flags: C

20. 13) RRF
•Syntax: Label RRF f, d
•Description: Rotate f
content right through
Carry
•Operation:
Result to w, if d = 0 and
Result to f, if d = 1
•Operand: 0 < f < 127
•No. of words: 1
•No. cycles: 1
•Flags: C
14) COMF
•Syntax: Label COMF f, d
•Description: Complement
the register content
•Operation:
Result to w, if d = 0 and
Result to f, if d = 1
•Operand: 0 < f < 127
•No. of words: 1
•No. cycles: 1
•Flags: Z

21. Bit Operation
1)BCF
Bit clearing flag or bit
clearing command
•Syntax: Label BCF f, b
•Description: Reset the
specified bit of register f
•Operation: Result to f
•Operand: 0 < f < 127 and
0 < b < 7
•No. of words: 1
•No. cycles: 1
•Flags: nil
2 ) BSF
Inversing operation of
BCF.
•Syntax: Label BSF f, b
•Description: Set the
specified bit of register f
•Operation: Result to f
•Operand: 0 < f < 127 and
0 < b < 7
•No. of words: 1
•No. cycles: 1
•Flags: nil

22. Program Sequence Control Operations:
1) BTFSC
•Current program flow.
•Syntax: Label BTFSC f, b
•Description: Test the specified
bit of register f, skip the next
instruction if it is zero
•Operation: Skip the next
instruction if f (b) = 0
•Operand: 0 < f < 127 and 0 < b
< 7
•No. of words: 1
•No. cycles: 1 or 2 depends on
bit value
•Flags: NIL
2) BTFSS
•Program flow control
instruction.
•Syntax: Label BTFSS f, b
•Description: Test the specified
bit of register f, skip the next
instruction if it is one
•Operation: Skip the next
instruction if f (b) = 1
•Operand: 0 < f < 127 and 0 < b
< 7
•No. of words: 1
•No. cycles: 1 or 2 depends on
bit value
•Flags: nil

23. 3) INCFSZ
•INCFSZ is a content increment
command
•Syntax: Label INCFSZ f, d
•Description: Increment the f
content, skip the next
instruction if f is zero
•Operation: Skip the next
instruction if f = zero
•Operand: (f) + 1 = w if d = 0
and (f) + 1 = f if d = 1
•No. of words: 1
•No. cycles: 1 or 2 depends on
bit value
•Flags: nil
4) DECFSZ
•DECFSZ command Decrement
f content
•Syntax: Label DECFSZ f, d
•Description: Decrement the f
content, skip the next
instruction if f is zero
•Operation: Skip the next
instruction if f = zero
•Operand: (f) – 1 = w if d = 0
and (f) – 1 = f if d = 1
•No. of words: 1
•No. cycles: 1 or 2 depends on
bit value
•Flags: nil

24. 5) GOTO
•Syntax: Label GOTO Label
•Description:
Unconditional jump to
specified label
•Operation: k to PC(10:0),
PCLATH(4:3) to PC(12:11)
•Operand: 0 < k < 2048
•No. of words: 1
•No. cycles: 2
•Flags: nil
6) CALL
•Syntax: Label CALL Label
•Description:
Unconditional call the
label
•Operation: (PC) + 1 to Top
of stack, k to PC(10:0),
PCLATH(4:3) to PC(12:11)
•Operand: 0 < k < 2048
•No. of words: 1
•No. cycles: 2
•Flags: nil

25. 7) RETURN
•Syntax: Label RETURN
•Description:
Unconditional return from
subroutine
•Operation: Top of stack
to (PC)
•Operand: nil
•No. of words: 1
•No. cycles: 2
•Flags: nil
8) RETLW
•Syntax: Label RETLW k
•Description:
Unconditional return from
subroutine
•Operation: Top of stack
to (PC) and k loaded in w
register
•Operand: 0 < k < 255
•No. of words: 1
•No. cycles: 2
•Flags: nil

26. 9) RETFIE
•Syntax: Label RETFIE
•Description:
Unconditional return from
subroutine
•Operation: Top of stack
to (PC) and Global
Interrupt bit is enabled
•Operand: nil
•No. of words: 1
•No. cycles: 2
•Flags: nil
Other Instructions in
PIC
1) NOP
•Syntax: Label NOP
•Description: No
operation
•Operation: nil
•Operand: nil
•No. of words: 1
•No. cycles: 1
•Flags: nil

27. 2) CLRWDT
•Initialize watchdog timer
feature .
•Syntax: Label CLRWDT
•Description: Watchdog
timer and pre-scalar is
reset and TO and PD are
set
•Operation: 0 to WDT, 0 to
pre-scalar and Status bits
TO and PD are set
•Operand: TO and PD
•No. of words: 1
•No. cycles: 1
•Flags: nil
3) SLEEP
•Initialize Standby mode.
•Syntax: Label SLEEP
•Description: Goes into
low consumption, OSC is
stopped, Watchdog timer
and pre-scalar is reset and
TO and PD bits are set
•Operation: 0 to WDT, 0 to
pre-scalar and Status bits,
TO is set and PD is reset
•Operand: TO and PD
•No. of words: 1
•No. cycles: 1
•Flags: nil