37.1.1 Standard Instruction Set Details
ADDLW | ADD literal to W | |||
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Syntax: | ADDLW k | |||
Operands: | 0 ≤ k ≤ 255 | |||
Operation: | (W) + k → W | |||
Status Affected: | N, OV, C, DC, Z | |||
Encoding: |
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Description: | The contents of W are added to the 8-bit literal ‘k’ and the result is placed in W. | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘k’ | Process Data | Write to W |
Example: |
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Before Instruction W = 10h After Instruction W = 25h |
ADDWF | ADD W to f | |||
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Syntax: | ADDWF f {,d {,a}} | |||
Operands: | 0 ≤ f ≤ 255 d ∈ [0,1] a ∈ [0,1] | |||
Operation: | (W) + (f) → dest | |||
Status Affected: | N, OV, C, DC, Z | |||
Encoding: | 0010 | 01da | ffff | ffff |
Description: | Add W to register ‘f’. If ‘d’ is ‘0 ’, the result is stored in
W. If ‘d’ is ‘1 ’, the result is stored back in register ‘f’
(default).If ‘a’ is ‘ If ‘a’ is
‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write to destination |
Example: |
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Before Instruction W = 17h REG = 0C2h After Instruction W = 0D9h REG = 0C2h |
ADDWFC | ADD W and CARRY bit to f | |||
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Syntax: | ADDWFC f {,d {,a}} | |||
Operands: | 0 ≤ f ≤ 255 d ∈ [0,1] a ∈ [0,1] | |||
Operation: | (W) + (f) + (C) → dest | |||
Status Affected: | N,OV, C, DC, Z | |||
Encoding: |
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Description: | Add W, the CARRY flag and data memory location ‘f’. If ‘d’ is
‘0 ’, the result is placed in W. If ‘d’ is
‘1 ’, the result is placed in data memory location ‘f’.If ‘a’ is ‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write to destination |
Example: |
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Before
Instruction CARRY bit = REG = 02h W = 4Dh After Instruction CARRY
bit = REG = 02h W = 50h |
ANDLW | AND literal with W | |||
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Syntax: | ANDLW k | |||
Operands: | 0 ≤ k ≤ 255 | |||
Operation: | (W) .AND. k → W | |||
Status Affected: | N, Z | |||
Encoding: | 0000 | 1011 | kkkk | kkkk |
Description: | The contents of W are AND’ed with the 8-bit literal ‘k’. The result is placed in W. | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘k’ | Process Data | Write to W |
Example: |
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Before Instruction W = A3h After Instruction W = 03h |
ANDWF | AND W with f | |||
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Syntax: | ANDWF f {,d {,a}} | |||
Operands: | 0 ≤ f ≤ 255 d ∈ [0,1] a ∈ [0,1] | |||
Operation: | (W) .AND. (f) → dest | |||
Status Affected: | N, Z | |||
Encoding: | 0001 | 01da | ffff | ffff |
Description: | The contents of W are AND’ed with register ‘f’. If ‘d’ is
‘0 ’, the result is stored in W. If ‘d’ is
‘1 ’, the result is stored back in register ‘f’ (default).If ‘a’ is ‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write to destination |
Example: |
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Before Instruction W = 17h REG = C2h After Instruction W = 02h REG = C2h |
BC | Branch if Carry | |||
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Syntax: | BC n | |||
Operands: | -128 ≤ n ≤ 127 | |||
Operation: | if CARRY bit is ‘1 ’(PC) + 2 + 2n → PC | |||
Status Affected: | None | |||
Encoding: | 1110 | 0010 | nnnn | nnnn |
Description: | If the CARRY bit is ‘1 ’, then the program will branch.The two’s complement number ‘2n’ is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC + 2 + 2n. This instruction is then a two-cycle instruction. | |||
Words: | 1 | |||
Cycles: | 1(2) |
Q Cycle Activity: If Jump: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘n’ | Process Data | Write to PC | |
No operation | No operation | No operation | No operation | |
If No Jump: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘n’ | Process Data | No operation |
Example: |
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Before
Instruction PC = address (HERE) After Instruction If
CARRY = If CARRY = |
BCF | Bit Clear f | |||
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Syntax: | BCF f, b {,a} | |||
Operands: | 0 ≤ f ≤ 255 0 ≤ b ≤ 7 a ∈ [0,1] | |||
Operation: | 0 → f<b> | |||
Status Affected: | None | |||
Encoding: | 1001 | bbba | ffff | ffff |
Description: | Bit ‘b’ in register ‘f’ is cleared. If ‘a’ is
‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write register ‘f’ |
Example: |
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Before Instruction FLAG_REG = C7h After Instruction FLAG_REG = 47h |
BN | Branch if Negative | |||
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Syntax: | BN n | |||
Operands: | -128 ≤ n ≤ 127 | |||
Operation: | if NEGATIVE bit is ‘1 ’(PC) + 2 + 2n → PC | |||
Status Affected: | None | |||
Encoding: | 1110 | 0110 | nnnn | nnnn |
Description: | If the NEGATIVE bit is ‘1 ’, then the program will branch.The two’s complement number ‘2n’ is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC + 2 + 2n. This instruction is then a two-cycle instruction. | |||
Words: | 1 | |||
Cycles: | 1(2) |
Q Cycle Activity: If Jump: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘n’ | Process Data | Write to PC | |
No operation | No operation | No operation | No operation | |
If No Jump: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘n’ | Process Data | No operation |
Example: |
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Before
Instruction PC = address (HERE) After Instruction If
NEGATIVE = If NEGATIVE = |
BNC | Branch if Not Carry | |||
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Syntax: | BNC n | |||
Operands: | -128 ≤ n ≤ 127 | |||
Operation: | if CARRY bit is ‘0 ’(PC) + 2 + 2n → PC | |||
Status Affected: | None | |||
Encoding: | 1110 | 0011 | nnnn | nnnn |
Description: | If the CARRY bit is ‘0 ’, then the program will branch.The two’s complement number ‘2n’ is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC + 2 + 2n. This instruction is then a two-cycle instruction. | |||
Words: | 1 | |||
Cycles: | 1(2) |
Q Cycle Activity: If Jump: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘n’ | Process Data | Write to PC | |
No operation | No operation | No operation | No operation | |
If No Jump: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘n’ | Process Data | No operation |
Example: |
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Before
Instruction PC = address (HERE) After Instruction If
CARRY = If CARRY = |
BNN | Branch if Not Negative | |||
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Syntax: | BNN n | |||
Operands: | -128 ≤ n ≤ 127 | |||
Operation: | if NEGATIVE bit is ‘0 ’(PC) + 2 + 2n → PC | |||
Status Affected: | None | |||
Encoding: | 1110 | 0111 | nnnn | nnnn |
Description: | If the NEGATIVE bit is ‘0 ’, then the program will branch.The two’s complement number ‘2n’ is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC + 2 + 2n. This instruction is then a two-cycle instruction. | |||
Words: | 1 | |||
Cycles: | 1(2) |
Q Cycle Activity: If Jump: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘n’ | Process Data | Write to PC | |
No operation | No operation | No operation | No operation | |
If No Jump: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘n’ | Process Data | No operation |
Example: |
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Before
Instruction PC = address (HERE) After Instruction If
NEGATIVE = If NEGATIVE = |
BNOV | Branch if Not Overflow | |||
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Syntax: | BNOV n | |||
Operands: | -128 ≤ n ≤ 127 | |||
Operation: | if OVERFLOW bit is ‘0 ’(PC) + 2 + 2n → PC | |||
Status Affected: | None | |||
Encoding: | 1110 | 0101 | nnnn | nnnn |
Description: | If the OVERFLOW bit is ‘0 ’, then the program will branch.The two’s complement number ‘2n’ is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC + 2 + 2n. This instruction is then a two-cycle instruction. | |||
Words: | 1 | |||
Cycles: | 1(2) |
Q Cycle Activity: If Jump: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘n’ | Process Data | Write to PC | |
No operation | No operation | No operation | No operation | |
If No Jump: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘n’ | Process Data | No operation |
Example: |
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Before
Instruction PC = address (HERE) After Instruction If
OVERFLOW = If OVERFLOW = |
BNZ | Branch if Not Zero | |||
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Syntax: | BNZ n | |||
Operands: | -128 ≤ n ≤ 127 | |||
Operation: | if ZERO bit is ‘0 ’(PC) + 2 + 2n → PC | |||
Status Affected: | None | |||
Encoding: | 1110 | 0001 | nnnn | nnnn |
Description: | If the ZERO bit is ‘0 ’, then the program will branch.The two’s complement number ‘2n’ is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC + 2 + 2n. This instruction is then a two-cycle instruction. | |||
Words: | 1 | |||
Cycles: | 1(2) |
Q Cycle Activity: If Jump: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘n’ | Process Data | Write to PC | |
No operation | No operation | No operation | No operation | |
If No Jump: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘n’ | Process Data | No operation |
Example: |
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Before
Instruction PC = address (HERE) After Instruction If
ZERO = If ZERO = |
BRA | Unconditional Branch | |||
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Syntax: | BRA n | |||
Operands: | -1024 ≤ n ≤ 1023 | |||
Operation: | (PC) + 2 + 2n → PC | |||
Status Affected: | None | |||
Encoding: | 1101 | 0nnn | nnnn | nnnn |
Description: | Add the two’s complement number ‘2n’ to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC + 2 + 2n. This instruction is a two-cycle instruction. | |||
Words: | 1 | |||
Cycles: | 2 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘n’ | Process Data | Write to PC | |
No operation | No operation | No operation | No operation |
Example: |
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Before Instruction PC = address (HERE) After Instruction PC = address (Jump) |
BSF | Bit Set f | |||
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Syntax: | BSF f, b {,a} | |||
Operands: | 0 ≤ f ≤ 255 0 ≤ b ≤ 7 a ∈ [0,1] | |||
Operation: | 1 → f<b> | |||
Status Affected: | None | |||
Encoding: | 1000 | bbba | ffff | ffff |
Description: | Bit ‘b’ in register ‘f’ is set. If ‘a’ is
‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write register ‘f’ |
Example: |
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Before Instruction FLAG_REG = 0Ah After Instruction FLAG_REG = 8Ah |
BTFSC | Bit Test File, Skip if Clear | |||
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Syntax: | BTFSC f, b {,a} | |||
Operands: | 0 ≤ f ≤ 255 0 ≤ b ≤ 7 a ∈ [0,1] | |||
Operation: | skip if (f<b>) = 0 | |||
Status Affected: | None | |||
Encoding: | 1011 | bbba | ffff | ffff |
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.If ‘a’ is ‘ If ‘a’ is
‘ | |||
Words: | 1 | |||
Cycles: | 1(2) Note: Three cycles if skip and followed by a two-word instruction. |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | No operation |
If skip: | ||||
Q1 | Q2 | Q3 | Q4 | |
No operation | No operation | No operation | No operation | |
If skip and followed by two-word instruction: | ||||
Q1 | Q2 | Q3 | Q4 | |
No operation | No operation | No operation | No operation | |
No operation | No operation | No operation | No operation | |
Example: |
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Before
Instruction PC = address (HERE) After Instruction If
FLAG<1> = If FLAG<1> = |
BTFSS | Bit Test File, Skip if Set | |||
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Syntax: | BTFSS f, b {,a} | |||
Operands: | 0 ≤ f ≤ 255 0 ≤ b < 7 a ∈ [0,1] | |||
Operation: | skip if (f<b>) = 1 | |||
Status Affected: | None | |||
Encoding: | 1010 | bbba | ffff | ffff |
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.If ‘a’ is ‘ If ‘a’ is
‘ | |||
Words: | 1 | |||
Cycles: | 1(2) Note: Three cycles if skip and followed by a two-word instruction. |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | No operation |
If skip: | ||||
Q1 | Q2 | Q3 | Q4 | |
No operation | No operation | No operation | No operation | |
If skip and followed by two-word instruction: | ||||
Q1 | Q2 | Q3 | Q4 | |
No operation | No operation | No operation | No operation | |
No operation | No operation | No operation | No operation |
Example: |
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Before
Instruction PC = address (HERE) After Instruction If
FLAG<1> = PC = address (FALSE) If FLAG<1> =
PC = address (TRUE) |
BTG | Bit Toggle f | |||
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Syntax: | BTG f, b {,a} | |||
Operands: | 0 ≤ f ≤ 255 0 ≤ b < 7 a ∈ [0,1] | |||
Operation: | (f<b>) → f<b> | |||
Status Affected: | None | |||
Encoding: | 0111 | bbba | ffff | ffff |
Description: | Bit ‘b’ in data memory location ‘f’ is inverted. If
‘a’ is ‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write register ‘f’ |
Example: |
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Before Instruction: PORTC = 0111 0101 [75h] After Instruction: PORTC = 0110 0101 [65h] |
BOV | Branch if Overflow | |||
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Syntax: | BOV n | |||
Operands: | -128 ≤ n ≤ 127 | |||
Operation: | if OVERFLOW bit is ‘1 ’(PC) + 2 + 2n → PC | |||
Status Affected: | None | |||
Encoding: | 1110 | 0100 | nnnn | nnnn |
Description: | If the OVERFLOW bit is ‘1 ’, then the program will branch.The two’s complement number ‘2n’ is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC + 2 + 2n. This instruction is then a two-cycle instruction. | |||
Words: | 1 | |||
Cycles: | 1(2) |
Q Cycle Activity: If Jump: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘n’ | Process Data | Write to PC | |
No operation | No operation | No operation | No operation | |
If No Jump: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘n’ | Process Data | No operation |
Example: |
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Before
Instruction PC = address (HERE) After Instruction If
OVERFLOW = If OVERFLOW = |
BZ | Branch if Zero | |||
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Syntax: | BZ n | |||
Operands: | -128 ≤ n ≤ 127 | |||
Operation: | if ZERO bit is ‘1 ’(PC) + 2 + 2n → PC | |||
Status Affected: | None | |||
Encoding: | 1110 | 0000 | nnnn | nnnn |
Description: | If the ZERO bit is ‘1 ’, then the program will branch.The two’s complement number ‘2n’ is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC + 2 + 2n. This instruction is then a two-cycle instruction. | |||
Words: | 1 | |||
Cycles: | 1(2) |
Q Cycle Activity: If Jump: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘n’ | Process Data | Write to PC | |
No operation | No operation | No operation | No operation | |
If No Jump: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘n’ | Process Data | No operation |
Example: |
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Before
Instruction PC = address (HERE) After Instruction If
ZERO = If ZERO = |
CALL | Subroutine Call | |||
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Syntax: | CALL k {,s} | |||
Operands: | 0 ≤ k ≤ 1048575 s ∈ [0,1] | |||
Operation: | (PC) + 4 → TOS, k → PC<20:1>, if s = 1 (W) → WS, (Status) → STATUSS, (BSR) → BSRS | |||
Status Affected: | None | |||
Encoding: 1st word (k<7:0>) 2nd word(k<19:8>) | 1110 1111 | 110s k19kkk | k7kkk kkkk | kkkk0 kkkk8 |
Description: | Subroutine call of entire 2-Mbyte memory range. First, return address (PC + 4)
is pushed onto the return stack. If ‘s’ = 1 , the W, Status and
BSR registers are also pushed into their respective shadow registers, WS,
STATUSS and BSRS. If ‘s’ = 0 , no update occurs (default).
Then, the 20-bit value ‘k’ is loaded into PC<20:1>. CALL is a two-cycle
instruction. | |||
Words: | 2 | |||
Cycles: | 2 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘k’<7:0>, | PUSH PC to stack | Read literal ‘k’<19:8>, Write to PC | |
No operation | No operation | No operation | No operation |
Example: |
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Before Instruction PC = address (HERE) After Instruction PC = address (THERE) TOS = address (HERE + 4) WS = W BSRS = BSR STATUSS = Status |
CLRF | Clear f | |||
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Syntax: | CLRF f {,a} | |||
Operands: | 0 ≤ f ≤ 255 a ∈ [0,1] | |||
Operation: | 000h → f 1 → Z | |||
Status Affected: | Z | |||
Encoding: | 0110 | 101a | ffff | ffff |
Description: | Clears the contents of the specified register. If ‘a’
is ‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write register ‘f’ |
Example: |
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Before Instruction FLAG_REG = 5Ah After Instruction FLAG_REG = 00h |
CLRWDT | Clear Watchdog Timer | |||
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Syntax: | CLRWDT | |||
Operands: | None | |||
Operation: | 000h → WDT, 000h → WDT postscaler, 1 → TO, 1 → PD | |||
Status Affected: | TO, PD | |||
Encoding: | 0000 | 0000 | 0000 | 0100 |
Description: | CLRWDT instruction resets the Watchdog Timer. It also resets the postscaler of the WDT. Status bits, TO and PD, are set. | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | No operation | Process Data | No operation |
Example: |
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Before
Instruction WDT Counter = ? After Instruction WDT Counter = 00h WDT Postscaler =
TO = PD =
|
COMF | Complement f | |||
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Syntax: | COMF f {,d {,a}} | |||
Operands: | 0 ≤ f ≤ 255 d ∈ [0,1] a ∈ [0,1] | |||
Operation: | (f) → dest | |||
Status Affected: | N, Z | |||
Encoding: | 0001 | 11da | ffff | ffff |
Description: | The contents of register ‘f’ are complemented. If ‘d’ is ‘0 ’,
the result is stored in W. If ‘d’ is ‘1 ’, the result is stored
back in register ‘f’ (default).If ‘a’ is
‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write to destination | |
Example: |
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Before Instruction REG = 13h After Instruction REG = 13h W = ECh |
CPFSEQ | Compare f with W, skip if f = W | |||
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Syntax: | CPFSEQ f {,a} | |||
Operands: | 0 ≤ f ≤ 255 a ∈ [0,1] | |||
Operation: | (f) – (W), skip if (f) = (W) (unsigned comparison) | |||
Status Affected: | None | |||
Encoding: | 0110 | 001a | ffff | ffff |
Description: | Compares the contents of data memory location ‘f’ to the contents of W by
performing an unsigned subtraction. If ‘f’ = W, then
the fetched instruction is discarded and a If ‘a’ is ‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1(2) Note: Three cycles if skip and followed by a two-word instruction. |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | No operation |
If skip: | ||||
Q1 | Q2 | Q3 | Q4 | |
No operation | No operation | No operation | No operation | |
If skip and followed by two-word instruction: | ||||
Q1 | Q2 | Q3 | Q4 | |
No operation | No operation | No operation | No operation | |
No operation | No operation | No operation | No operation |
Example: |
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Before Instruction PC Address = HERE W = ? REG = ? After Instruction If REG = W; PC = Address (EQUAL) If REG ≠ ; PC = Address (NEQUAL) |
CPFSGT | Compare f with W, skip if f > W | |||
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Syntax: | CPFSGT f {,a} | |||
Operands: | 0 ≤ f ≤ 255 a ∈ [0,1] | |||
Operation: | (f) – (), skip if (f) > (W) (unsigned comparison) | |||
Status Affected: | None | |||
Encoding: | 0110 | 010a | ffff | ffff |
Description: | Compares the contents of data memory location ‘f’ to the contents of the W by
performing an unsigned subtraction. If the contents of
‘f’ are greater than the contents of WREG, then the fetched instruction is
discarded and a If ‘a’ is
‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1(2) Note: Three cycles if skip and followed by a two-word instruction. |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | No operation |
If skip: | ||||
Q1 | Q2 | Q3 | Q4 | |
No operation | No operation | No operation | No operation | |
If skip and followed by two-word instruction: | ||||
Q1 | Q2 | Q3 | Q4 | |
No operation | No operation | No operation | No operation | |
No operation | No operation | No operation | No operation |
Example: |
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Before Instruction PC = Address (HERE) W = ? After Instruction If REG > W; PC = Address (GREATER) If REG ≤ W; PC = Address (NGREATER) |
CPFSLT | Compare f with W, skip if f < W | |||
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Syntax: | CPFSLT f {,a} | |||
Operands: | 0 ≤ f ≤ 255 a ∈ [0,1] | |||
Operation: | (f) – (), skip if (f) < (W) (unsigned comparison) | |||
Status Affected: | None | |||
Encoding: | 0110 | 000a | ffff | ffff |
Description: | Compares the contents of data memory location ‘f’ to the contents of W by
performing an unsigned subtraction. If the contents of
‘f’ are less than the contents of W, then the fetched instruction is
discarded and a If ‘a’ is
‘ | |||
Words: | 1 | |||
Cycles: | 1(2) Note: Three cycles if skip and followed by a two-word instruction. |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | No operation |
If skip: | ||||
Q1 | Q2 | Q3 | Q4 | |
No operation | No operation | No operation | No operation | |
If skip and followed by two-word instruction: | ||||
Q1 | Q2 | Q3 | Q4 | |
No operation | No operation | No operation | No operation | |
No operation | No operation | No operation | No operation |
Example: |
| |||
Before Instruction PC = Address (HERE) W = ? After Instruction If REG < W; PC = Address (LESS) If REG ≥ W; PC = Address (NLESS) |
DAW | Decimal Adjust W Register | |||
---|---|---|---|---|
Syntax: | DAW | |||
Operands: | None | |||
Operation: | If [W<3:0> > 9] or [DC = 1] then (W<3:0>) + 6 → W<3:0>; else (W<3:0>) → W<3:0>; If [W<7:4> + DC > 9] or [C = 1] then (W<7:4>) + 6 + DC → W<7:4> ; else (W<7:4>) + DC → W<7:4> | |||
Status Affected: | C | |||
Encoding: | 0000 | 0000 | 0000 | 0111 |
Description: | DAW adjusts the 8-bit value in W, resulting from the earlier addition of two variables (each in packed BCD format) and produces a correct packed BCD result. | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register W | Process Data | Write W |
Example1: |
| |||
Before Instruction W = A5h C = 0 DC = 0 After Instruction W = 05h C = 1 DC = 0 Example 2: Before Instruction W = CEh C = 0 DC = 0 After Instruction W = 34h C = 1 DC = 0 |
DECF | Decrement f | |||
---|---|---|---|---|
Syntax: | DECF f {,d {,a}} | |||
Operands: | 0 ≤ f ≤ 255 d ∈ [0,1] a ∈ [0,1] | |||
Operation: | (f) – 1 → dest | |||
Status Affected: | C, DC, N, OV, Z | |||
Encoding: | 0000 | 01da | ffff | ffff |
Description: | Decrement register ‘f’. If ‘d’ is ‘0 ’, the result is stored
in W. If ‘d’ is ‘1 ’, the result is stored back in register ‘f’
(default).If ‘a’ is ‘ If ‘a’ is
‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write to destination |
Example: |
|
| ||
Before Instruction CNT = 01h Z = 0 After Instruction CNT = 00h Z = 1 |
DECFSZ | Decrement f, skip if 0 | |||
---|---|---|---|---|
Syntax: | DECFSZ f {,d {,a}} | |||
Operands: | 0 ≤ f ≤ 255 d ∈ [0,1] a ∈ [0,1] | |||
Operation: | (f) – 1 → dest, skip if result = 0 | |||
Status Affected: | None | |||
Encoding: | 0010 | 11da | ffff | ffff |
Description: | The contents of register ‘f’ are decremented. If ‘d’ is ‘0 ’,
the result is placed in W. If ‘d’ is ‘1 ’, the result is placed
back in register ‘f’ (default).If the result is
‘ If ‘a’ is
‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1(2) Note: Three cycles if skip and followed by a two-word instruction. |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write to destination |
If skip: | ||||
Q1 | Q2 | Q3 | Q4 | |
No operation | No operation | No operation | No operation | |
If skip and followed by two-word instruction: | ||||
Q1 | Q2 | Q3 | Q4 | |
No operation | No operation | No operation | No operation | |
No operation | No operation | No operation | No operation |
Example: |
| |||
Before Instruction PC = Address (HERE) After Instruction CNT = CNT - 1 If CNT = 0; PC = Address (CONTINUE) If CNT ≠ 0; PC = Address (HERE + 2) |
DCFSNZ | Decrement f, skip if not 0 | |||
---|---|---|---|---|
Syntax: | DCFSNZ f {,d {,a}} | |||
Operands: | 0 ≤ f ≤ 255 d ∈ [0,1] a ∈ [0,1] | |||
Operation: | (f) – 1 → dest, skip if result ≠ 0 | |||
Status Affected: | None | |||
Encoding: | 0100 | 11da | ffff | ffff |
Description: | The contents of register ‘f’ are decremented. If ‘d’ is ‘0 ’,
the result is placed in W. If ‘d’ is ‘1 ’, the result is placed
back in register ‘f’ (default).If the result is not
‘ If ‘a’ is
‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1(2) Note: Three cycles if skip and followed by a two-word instruction. |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write to destination |
If skip: | ||||
Q1 | Q2 | Q3 | Q4 | |
No operation | No operation | No operation | No operation | |
If skip and followed by two-word instruction: | ||||
Q1 | Q2 | Q3 | Q4 | |
No operation | No operation | No operation | No operation | |
No operation | No operation | No operation | No operation |
Example: |
| |||
Before Instruction TEMP = ? After Instruction TEMP = TEMP – 1, If TEMP = 0; PC = Address (ZERO) If TEMP ≠ 0; PC = Address (NZERO) |
GOTO | Unconditional Branch | |||
---|---|---|---|---|
Syntax: | GOTO k | |||
Operands: | 0 ≤ k ≤ 1048575 | |||
Operation: | k → PC<20:1> | |||
Status Affected: | None | |||
Encoding: 1st word (k<7:0>) 2nd word(k<19:8>) | 1110 1111 | 1111 k19kkk | k7kkk kkkk | kkkk0 kkkk8 |
Description: | GOTO allows an unconditional branch anywhere within entire
2-Mbyte memory range. The 20-bit value ‘k’ is loaded into PC<20:1>.
GOTO is always a two-cycle instruction. | |||
Words: | 2 | |||
Cycles: | 2 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘k’<7:0>, | No operation | Read literal ‘k’<19:8>, Write to PC | |
No operation | No operation | No operation | No operation |
Example: |
| |||
After Instruction PC = Address (THERE) |
INCF | Increment f | |||
---|---|---|---|---|
Syntax: | INCF f {,d {,a}} | |||
Operands: | 0 ≤ f ≤ 255 d ∈ [0,1] a ∈ [0,1] | |||
Operation: | (f) + 1 → dest | |||
Status Affected: | C, DC, N, OV, Z | |||
Encoding: | 0010 | 10da | ffff | ffff |
Description: | The contents of register ‘f’ are incremented. If ‘d’ is ‘0 ’,
the result is placed in W. If ‘d’ is ‘1 ’, the result is placed
back in register ‘f’ (default).If ‘a’ is
‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write to destination |
Example: |
|
|
| |
Before Instruction CNT = FFh Z = 0 C = ? DC = ? After Instruction CNT = 00h Z = 1 C = 1 DC = 1 |
INCFSZ | Increment f, skip if 0 | |||
---|---|---|---|---|
Syntax: | INCFSZ f {,d {,a}} | |||
Operands: | 0 ≤ f ≤ 255 d ∈ [0,1] a ∈ [0,1] | |||
Operation: | (f) + 1 → dest, skip if result = 0 | |||
Status Affected: | None | |||
Encoding: | 0011 | 11da | ffff | ffff |
Description: | The contents of register ‘f’ are incremented. If ‘d’ is ‘0 ’,
the result is placed in W. If ‘d’ is ‘1 ’, the result is placed
back in register ‘f’ (default).If the result is
‘ If ‘a’ is
‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1(2) Note: Three cycles if skip and followed by a two-word instruction. |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write to destination |
If skip: | ||||
Q1 | Q2 | Q3 | Q4 | |
No operation | No operation | No operation | No operation | |
If skip and followed by two-word instruction: | ||||
Q1 | Q2 | Q3 | Q4 | |
No operation | No operation | No operation | No operation | |
No operation | No operation | No operation | No operation |
Example: |
| |||
Before Instruction PC = Address (HERE) After Instruction CNT = CNT + 1 If CNT = 0; PC = Address (ZERO) If CNT ≠ 0; PC = Address (NZERO) |
INFSNZ | Increment f, skip if not 0 | |||
---|---|---|---|---|
Syntax: | INFSNZ f {,d {,a}} | |||
Operands: | 0 ≤ f ≤ 255 d ∈ [0,1] a ∈ [0,1] | |||
Operation: | (f) + 1 → dest, skip if result ≠ 0 | |||
Status Affected: | None | |||
Encoding: | 0100 | 10da | ffff | ffff |
Description: | The contents of register ‘f’ are incremented. If ‘d’ is ‘0 ’,
the result is placed in W. If ‘d’ is ‘1 ’, the result is placed
back in register ‘f’ (default).If the result is not
‘ If ‘a’ is
‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1(2) Note: Three cycles if skip and followed by a two-word instruction. |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write to destination |
If skip: | ||||
Q1 | Q2 | Q3 | Q4 | |
No operation | No operation | No operation | No operation | |
If skip and followed by two-word instruction: | ||||
Q1 | Q2 | Q3 | Q4 | |
No operation | No operation | No operation | No operation | |
No operation | No operation | No operation | No operation |
Example: |
| |||
Before Instruction PC = Address (HERE) After Instruction REG = REG + 1 If REG ≠ 0; PC = Address (NZERO) If REG = 0; PC = Address (ZERO) |
IORLW | Inclusive OR literal with W | |||
---|---|---|---|---|
Syntax: | IORLW k | |||
Operands: | 0 ≤ k ≤ 255 | |||
Operation: | (W) .OR. k → W | |||
Status Affected: | N, Z | |||
Encoding: | 0000 | 1001 | kkkk | kkkk |
Description: | The contents of W are ORed with the 8-bit literal ‘k’. The result is placed in W. | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘k’ | Process Data | Write to W |
Example: |
|
| ||
Before Instruction W = 9Ah After Instruction W = BFh |
IORWF | Inclusive OR W with f | |||
---|---|---|---|---|
Syntax: | IORWF f {,d {,a}} | |||
Operands: | 0 ≤ f ≤ 255 d ∈ [0,1] a ∈ [0,1] | |||
Operation: | (W) .OR. (f) → dest | |||
Status Affected: | N, Z | |||
Encoding: | 0001 | 00da | ffff | ffff |
Description: | Inclusive OR W with register ‘f’. If ‘d’ is ‘0 ’, the result
is placed in W. If ‘d’ is ‘1 ’, the result is placed back in
register ‘f’ (default).If ‘a’ is
‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write to destination |
Example: |
| |||
Before Instruction RESULT = 13h W = 91h After Instruction RESULT = 13h W = 93h |
LFSR | Load FSR | |||
---|---|---|---|---|
Syntax: | LFSR f, k | |||
Operands: | 0 ≤ f ≤ 2 0 ≤ k ≤ 4095 | |||
Operation: | k → FSRf | |||
Status Affected: | None | |||
Encoding: | 1110 1111 | 1110 0000 | 00ff k7kkk | k11kkk kkkk |
Description: | The 12-bit literal ‘k’ is loaded into the File Select Register pointed to by ‘f’. | |||
Words: | 2 | |||
Cycles: | 2 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘k’ MSB | Process Data | Write literal ‘k’ MSB to FSRfH | |
Decode | Read literal ‘k’ LSB | Process Data | Write literal ‘k’ to FSRfL |
Example: |
| |||
After Instruction FSR2H = 03h FSR2L = ABh |
MOVF | Move f | |||
---|---|---|---|---|
Syntax: | MOVF f {,d {,a}} | |||
Operands: | 0 ≤ f ≤ 255 d ∈ [0,1] a ∈ [0,1] | |||
Operation: | f → dest | |||
Status Affected: | N, Z | |||
Encoding: | 0101 | 00da | ffff | ffff |
Description: | The contents of register ‘f’ are moved to a destination dependent upon the
status of ‘d’. If ‘d’ is ‘0 ’, the result is placed in W. If
‘d’ is ‘1 ’, the result is placed back in register ‘f’
(default). Location ‘f’ can be anywhere in the 256-byte bank.If ‘a’ is ‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write W |
Example: |
| |||
Before Instruction REG = 22h W = FFh After Instruction REG = 22h W = 22h |
MOVFF | Move f to f | |||
---|---|---|---|---|
Syntax: | MOVFF fs,fd | |||
Operands: | 0 ≤ fs ≤ 4095 0 ≤ fd ≤ 4095 | |||
Operation: | (fs) → fd | |||
Status Affected: | None | |||
Encoding: 1st word (source) 2nd word (destin.) | 1100 1111 | ffff ffff | ffff ffff | ffffs ffffd |
Description: | The contents of source register ‘fs’ are
moved to destination register ‘fd’. The
location of source ‘fs’ can be anywhere in
the 4096-byte data space (000h to FFFh) and location of destination ‘fd’ can also be anywhere from 000h to FFFh. Either source or destination can be W (a useful special situation). MOVFF is particularly useful for transferring a data memory location to a peripheral register (such as the transmit buffer or an I/O port). The MOVFF instruction cannot use the PCL, TOSU, TOSH or TOSL as the destination register. | |||
Words: | 2 | |||
Cycles: | 2 (3) |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ (src) | Process Data | No operation | |
Decode | No operation No dummy read | No operation | Write register ‘f’ (dest) |
Example: |
| |||
Before Instruction REG1 = 33h REG2 = 11h After Instruction REG1 = 33h REG2 = 33h |
MOVLB | Move literal to low nibble in BSR | |||
---|---|---|---|---|
Syntax: | MOVLW k | |||
Operands: | 0 ≤ k ≤ 255 | |||
Operation: | k → BSR | |||
Status Affected: | None | |||
Encoding: | 0000 | 0001 | kkkk | kkkk |
Description: | The 8-bit literal ‘k’ is loaded into the Bank Select Register (BSR). The value of BSR<7:4> always remains ‘0’, regardless of the value of k7:k4. | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘k’ | Process Data | Write literal ‘k’ to BSR |
Example: |
|
| ||
Before Instruction BSR Register = 02h After Instruction BSR Register = 05h |
MOVLW | Move literal to W | |||
---|---|---|---|---|
Syntax: | MOVLW k | |||
Operands: | 0 ≤ k ≤ 255 | |||
Operation: | k → W | |||
Status Affected: | None | |||
Encoding: | 0000 | 1110 | kkkk | kkkk |
Description: | The 8-bit literal ‘k’ is loaded into W. | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘k’ | Process Data | Write to W |
Example: |
|
| ||
After Instruction W = 5Ah |
MOVWF | Move W to f | |||
---|---|---|---|---|
Syntax: | MOVWF f {,a} | |||
Operands: | 0 ≤ f ≤ 255 a ∈ [0,1] | |||
Operation: | (W) → f | |||
Status Affected: | None | |||
Encoding: | 0110 | 111a | ffff | ffff |
Description: | Move data from W to register ‘f’. The location ‘f’ can be anywhere in the
256-byte bank. If ‘a’ is ‘ If ‘a’ is
‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write register ‘f’ |
Example: |
|
| ||
Before Instruction W = 4Fh REG = FFh After Instruction W = 4Fh REG = 4Fh |
MULLW | Multiply literal with W | |||
---|---|---|---|---|
Syntax: | MULLW k | |||
Operands: | 0 ≤ k ≤ 255 | |||
Operation: | (W) x k → PRODH:PRODL | |||
Status Affected: | None | |||
Encoding: | 0000 | 1101 | kkkk | kkkk |
Description: | An unsigned multiplication is carried out between the contents of W and the 8-bit literal ‘k’. The 16-bit result is placed in the PRODH:PRODL register pair. PRODH contains the high byte. W is unchanged. None of the Status flags are affected. Note that neither overflow nor carry is possible in this operation. A zero result is possible but not detected. | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘k’ | Process Data | Write registers PRODH:PRODL |
Example: |
| |||
Before Instruction W = E2h PRODH = ? PRODL = ? After Instruction W = E2h PRODH = ADh PRODL = 08h |
MULWF | Multiply W with f | |||
---|---|---|---|---|
Syntax: | MULWF f {,a} | |||
Operands: | 0 ≤ f ≤ 255 a ∈ [0,1] | |||
Operation: | (W) x (f) → PRODH:PRODL | |||
Status Affected: | None | |||
Encoding: | 0000 | 001a | ffff | ffff |
Description: | An unsigned multiplication is carried out between the contents of W and the
register file location ‘f’. The 16-bit result is stored in the PRODH:PRODL
register pair. PRODH contains the high byte. Both W and ‘f’ are unchanged. None of the Status flags are affected. Note that neither overflow nor carry is possible in this operation. A zero result is possible but not detected. If ‘a’ is ‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write registers PRODH:PRODL |
Example: |
| |||
Before Instruction W = C4h REG = B5h PRODH = ? PRODL = ? After Instruction W = C4h REG = B5h PRODH = 8Ah PRODL = 94h |
NEGF | Negate f | |||
---|---|---|---|---|
Syntax: | NEGF f {,a} | |||
Operands: | 0 ≤ f ≤ 255 a ∈ [0,1] | |||
Operation: | ( f ) + 1 → f | |||
Status Affected: | N, OV, C, DC, Z | |||
Encoding: | 0110 | 110a | ffff | ffff |
Description: | Location ‘f’ is negated using two’s complement. The result is placed in the
data memory location ‘f’. If ‘a’ is
‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write register ‘f’ |
Example: |
| |||
Before Instruction REG = 0011 1010 [3Ah] After Instruction REG = 1100 0110 [C6h] |
NOP | No Operation | |||
---|---|---|---|---|
Syntax: | NOP | |||
Operands: | None | |||
Operation: | No operation | |||
Status Affected: | None | |||
Encoding: | 0000 1111 | 0000 xxxx | 0000 xxxx | 0000 xxxx |
Description: | No operation. | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | No operation | No operation | No operation |
Example: | ||||
None. |
POP | Pop Top of Return Stack | |||
---|---|---|---|---|
Syntax: | POP | |||
Operands: | None | |||
Operation: | (TOS) → bit bucket | |||
Status Affected: | None | |||
Encoding: | 0000 | 0000 | 0000 | 0110 |
Description: | The TOS value is pulled off the return stack and is discarded. The TOS value then becomes the previous value that was pushed onto the return stack. This instruction is provided to enable the user to properly manage the return stack to incorporate a software stack. | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | No operation | POP TOS value | No operation |
Example: |
|
| ||
Before Instruction TOS = 0031A2h Stack (1 level down) = 014332h After Instruction TOS = 014332h PC = NEW |
PUSH | Push Top of Return Stack | |||
---|---|---|---|---|
Syntax: | PUSH | |||
Operands: | None | |||
Operation: | (PC + 2) → TOS | |||
Status Affected: | None | |||
Encoding: | 0000 | 0000 | 0000 | 0101 |
Description: | The PC + 2 is pushed onto the top of the return stack. The previous TOS value is pushed down on the stack. This instruction allows implementing a software stack by modifying TOS and then pushing it onto the return stack. | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | PUSH PC + 2 onto return stack | No operation | No operation |
Example: |
| |||
Before Instruction TOS = 345Ah PC = 0124h After Instruction PC = 0126h TOS = 0126h Stack (1 level down) = 345Ah |
RCALL | Relative Call | |||
---|---|---|---|---|
Syntax: | RCALL n | |||
Operands: | -1024 ≤ n ≤ 1023 | |||
Operation: | (PC) + 2 → TOS, (PC) + 2 + 2n → PC | |||
Status Affected: | None | |||
Encoding: | 1101 | 1nnn | nnnn | nnnn |
Description: | Subroutine call with a jump up to 1K from the current location. First, return address (PC + 2) is pushed onto the stack. Then, add the two’s complement number ‘2n’ to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC + 2 + 2n. This instruction is a two-cycle instruction. | |||
Words: | 1 | |||
Cycles: | 2 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘n’ PUSH PC to stack | Process Data | Write to PC | |
No operation | No operation | No operation | No operation |
Example: |
|
| Jump | |
Before Instruction PC = Address (HERE) After Instruction PC = Address (Jump) TOS = Address (HERE + 2) |
RESET | Reset | |||
---|---|---|---|---|
Syntax: | RESET | |||
Operands: | None | |||
Operation: | Reset all registers and flags that are affected by a MCLR Reset. | |||
Status Affected: | All | |||
Encoding: | 0000 | 0000 | 1111 | 1111 |
Description: | This instruction provides a way to execute a MCLR Reset by software. | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Start Reset | No operation | No operation |
Example: |
| |||
After Instruction Registers = Reset Value Flags* = Reset Value |
RETFIE | Return from Interrupt | |||
---|---|---|---|---|
Syntax: | RETFIE {s} | |||
Operands: | s ∈ [0,1] | |||
Operation: | (TOS) → PC, 1 → GIE/GIEH or PEIE/GIEL, if s = 1 (WS) → W, (STATUSS) → Status, (BSRS) → BSR, PCLATU, PCLATH are unchanged. | |||
Status Affected: | GIE/GIEH, PEIE/GIEL. | |||
Encoding: | 0000 | 0000 | 0001 | 000s |
Description: | Return from interrupt. Stack is popped and Top-of-Stack (TOS) is loaded into
the PC. Interrupts are enabled by setting either the high- or low-priority
Global Interrupt Enable bit. If ‘s’ = 1 , the contents of the
shadow registers, WS, STATUSS and BSRS, are loaded into their corresponding
registers, W, Status and BSR. If ‘s’ = 0 , no update of these
registers occurs (default). | |||
Words: | 1 | |||
Cycles: | 2 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | No operation | No operation | POP PC from stack Set GIEH or GIEL | |
No operation | No operation | No operation | No operation |
Example: |
| |||
After Interrupt PC = TOS W = WS BSR = BSRS Status = STATUSS GIE/GIEH, PEIE/GIEL = 1 |
RETLW | Return literal to W | |||
---|---|---|---|---|
Syntax: | RETLW k | |||
Operands: | 0 ≤ k ≤ 255 | |||
Operation: | k → W, (TOS) → PC, PCLATU, PCLATH are unchanged | |||
Status Affected: | None | |||
Encoding: | 0000 | 1100 | kkkk | kkkk |
Description: | W is loaded with the 8-bit literal ‘k’. The Program Counter is loaded from the top of the stack (the return address). The high address latch (PCLATH) remains unchanged. | |||
Words: | 1 | |||
Cycles: | 2 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘k’ | Process Data | POP PC from stack, Write to W | |
No operation | No operation | No operation | No operation |
Example:
| ||||
Before Instruction W = 07h After Instruction W = value of kn |
RETURN | Return from Subroutine | |||
---|---|---|---|---|
Syntax: | RETURN {s} | |||
Operands: | s ∈ [0,1] | |||
Operation: | (TOS) → PC, if s = 1 (WS) → W, (STATUSS) → Status, (BSRS) → BSR, PCLATU, PCLATH are unchanged | |||
Status Affected: | None | |||
Encoding: | 0000 | 0000 | 0001 | 001s |
Description: | Return from subroutine. The stack is popped and the top of the stack (TOS) is
loaded into the Program Counter. If ‘s’= 1 , the contents of
the shadow registers, WS, STATUSS and BSRS, are loaded into their corresponding
registers, W, Status and BSR. If ‘s’ = 0 , no update of these
registers occurs (default). | |||
Words: | 1 | |||
Cycles: | 2 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | No operation | Process Data | POP PC from stack | |
No operation | No operation | No operation | No operation | |
Example: |
| |||
After Instruction: PC = TOS |
RLCF | Rotate Left f through Carry | |||
---|---|---|---|---|
Syntax: | RLCF f {,d {,a}} | |||
Operands: | 0 ≤ f ≤ 255 d ∈ [0,1] a ∈ [0,1] | |||
Operation: | (f<n>) → dest<n + 1>, (f<7>) → C, (C) → dest<0> | |||
Status Affected: | C, N, Z | |||
Encoding: | 0011 | 01da | ffff | ffff |
Description: | 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 W. If ‘d’ is
‘1 ’, the result is stored back in register ‘f’ (default).If ‘a’ is ‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write to destination |
Example: |
|
| ||
Before Instruction REG = 1110 0110 C = 0 After Instruction REG = 1110 0110 W = 1100 1100 C = 1 |
RLNCF | Rotate Left f (No Carry) | |||
---|---|---|---|---|
Syntax: | RLNCF f {,d {,a}} | |||
Operands: | 0 ≤ f ≤ 255 d ∈ [0,1] a ∈ [0,1] | |||
Operation: | (f<n>) → dest<n + 1>, (f<7>) → dest<0> | |||
Status Affected: | N, Z | |||
Encoding: | 0100 | 01da | ffff | ffff |
Description: | The contents of register ‘f’ are rotated one bit to the left. If ‘d’ is
‘0 ’, the result is placed in W. If ‘d’ is
‘1 ’, the result is stored back in register ‘f’ (default).If ‘a’ is ‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write to destination |
Example: |
|
| ||
Before Instruction REG = 1010 1011 After Instruction REG = 0101 0111 |
RRCF | Rotate Right f through Carry | |||
---|---|---|---|---|
Syntax: | RRCF f {,d {,a}} | |||
Operands: | 0 ≤ f ≤ 255 d ∈ [0,1] a ∈ [0,1] | |||
Operation: | (f<n>) → dest<n – 1>, (f<0>) → C, (C) → dest<7> | |||
Status Affected: | C, N, Z | |||
Encoding: | 0011 | 00da | ffff | ffff |
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 W. If ‘d’
is ‘1 ’, the result is placed back in register ‘f’ (default).If ‘a’ is ‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write to destination |
Example: |
|
| ||
Before Instruction REG = 1110 0110 C = 0 After Instruction REG = 1110 0110 W = 0111 0011 C = 0 |
RRNCF | Rotate Right f (No Carry) | |||
---|---|---|---|---|
Syntax: | RRNCF f {,d {,a}} | |||
Operands: | 0 ≤ f ≤ 255 d ∈ [0,1] a ∈ [0,1] | |||
Operation: | (f<n>) → dest<n – 1>, (f<0>) → dest<7> | |||
Status Affected: | N, Z | |||
Encoding: | 0100 | 00da | ffff | ffff |
Description: | The contents of register ‘f’ are rotated one bit to the right. If ‘d’ is
‘0 ’, the result is placed in W. If ‘d’ is
‘1 ’, the result is placed back in register ‘f’ (default).If ‘a’ is ‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write to destination |
Example 1: |
| |||
Before Instruction REG = 1101 0111 After Instruction REG = 1110 1011 | ||||
Example 2: |
| |||
Before Instruction W = ? REG = 1101 0111 After Instruction W = 1110 1011 REG = 1101 0111 |
SETF | Set f | |||
---|---|---|---|---|
Syntax: | SETF f {,a} | |||
Operands: | 0 ≤ f ≤ 255 a ∈ [0,1] | |||
Operation: | FFh → f | |||
Status Affected: | None | |||
Encoding: | 0110 | 100a | ffff | ffff |
Description: | The contents of the specified register are set to FFh. If ‘a’ is ‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write register ‘f’ |
Example: |
|
| ||
Before Instruction REG = 5Ah After Instruction REG = FFh |
SLEEP | Enter Sleep mode | |||
---|---|---|---|---|
Syntax: | SLEEP | |||
Operands: | None | |||
Operation: | 00h → WDT, 0 → WDT postscaler, 1 → TO, 0 → PD | |||
Status Affected: | TO, PD | |||
Encoding: | 0000 | 0000 | 0000 | 0011 |
Description: | The Power-Down (PD) Status bit
is cleared. The Time-out (TO)
Status bit is set. Watchdog Timer and its postscaler are cleared. The processor is put into Sleep mode with the oscillator stopped. | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | No operation | Process Data | Go to Sleep |
Example: |
| |||
Before Instruction TO = ? PD = ? After Instruction TO = 1 † PD = 0 † If WDT causes wake-up, this bit is cleared. |
SUBFWB | Subtract f from W with borrow (Continued) | |||
---|---|---|---|---|
Syntax: | SUBFWB f {,d {,a}} | |||
Operands: | 0 ≤ f ≤ 255 d ∈ [0,1] a ∈ [0,1] | |||
Operation: | (W) – (f) – (C) → dest | |||
Status Affected: | N, OV, C, DC, Z | |||
Encoding: | 0101 | 01da | ffff | ffff |
Description: | Subtract register ‘f’ and CARRY flag (borrow) from W (two’s complement
method). If ‘d’ is ‘0 ’, the result is stored in W. If ‘d’ is
‘1 ’, the result is stored in register ‘f’ (default).If ‘a’ is ‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write to destination |
Example 1: |
| |||
Before Instruction REG = 3 W = 2 C = 1 After Instruction REG = FF W = 2 C = 0 Z = 0 N = 1 ; result is negative | ||||
Example 2: |
| |||
Before Instruction REG = 2 W = 5 C = 1 After Instruction REG = 2 W = 3 C = 1 Z = 0 N = 0 ; result is positive | ||||
Example 3: |
| |||
Before Instruction REG = 1 W = 2 C = 0 After Instruction REG = 0 W = 2 C = 1 Z = 1 ; result is zero N = 0 |
SUBLW | Subtract W from literal | |||
---|---|---|---|---|
Syntax: | SUBLW k | |||
Operands: | 0 ≤ k ≤ 255 | |||
Operation: | k – (W) → | |||
Status Affected: | N, OV, C, DC, Z | |||
Encoding: | 0000 | 1000 | kkkk | kkkk |
Description | W is subtracted from the 8-bit literal ‘k’. The result is placed in W. | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘k’ | Process Data | Write to W |
Example 1: |
|
| ||
Before Instruction W = 01h C = ? After Instruction W = 01h C = 1 ; result is positive Z = 0 N = 0 | ||||
Example 2: |
|
| ||
Before Instruction W = 02h C = ? After Instruction W = 00h C = 1 ; result is zero Z = 1 N = 0 | ||||
Example 3: |
|
| ||
Before
Instruction W = 03h C = ? After Instruction W = FFh ; (two’s complement) C = 0 ; result is negative Z = 0 N = 1 |
SUBWF | Subtract W from f | |||
---|---|---|---|---|
Syntax: | SUBWF f {,d {,a}} | |||
Operands: | 0 ≤ f ≤ 255 d ∈ [0,1] a ∈ [0,1] | |||
Operation: | (f) – (W) → dest | |||
Status Affected: | N, OV, C, DC, Z | |||
Encoding: | 0101 | 11da | ffff | ffff |
Description: | Subtract W from register ‘f’ (two’s complement method). If ‘d’ is
‘0 ’, the result is stored in W. If ‘d’ is
‘1 ’, the result is stored back in register ‘f’ (default).If ‘a’ is ‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write to destination |
Example 1: |
| |||
Before Instruction REG = 3 W = 2 C = ? After Instruction REG = 1 W = 2 C = 1 ; result is positive Z = 0 N = 0 | ||||
Example 2: |
| |||
Before Instruction REG = 2 W = 2 C = ? After Instruction REG = 2 W = 0 C = 1 ; result is zero Z = 1 N = 0 | ||||
Example 3: |
| |||
Before
Instruction REG = 1 W = 2 C = ? After Instruction REG = FFh ; (two’s complement) W = 2 C = 0 ; result is negative Z = 0 N = 1 |
SUBWFB | Subtract W from f with Borrow | |||
---|---|---|---|---|
Syntax: | SUBWFB f {,d {,a}} | |||
Operands: | 0 ≤ f ≤ 255 d ∈ [0,1] a ∈ [0,1] | |||
Operation: | (f) – (W) – (C) → dest | |||
Status Affected: | N, OV, C, DC, Z | |||
Encoding: | 0101 | 10da | ffff | ffff |
Description: | Subtract W and the CARRY flag (borrow) from register ‘f’ (two’s complement
method). If ‘d’ is ‘0 ’, the result is stored in W. If ‘d’ is
‘1 ’, the result is stored back in register ‘f’ (default).If ‘a’ is ‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write to destination |
Example 1: |
| |||
Before Instruction REG = 19h (0001 1001) W = 0Dh (0000 1101) C = 1 After Instruction REG = 0Ch (0000 1100) W = 0Dh (0000 1101) C = 1 Z = 0 N = 0 ; result is positive | ||||
Example 2: |
| |||
Before Instruction REG = 1Bh (0001 1011) W = 1Ah (0001 1010) C = 0 After Instruction REG = 1Bh (0001 1011) W = 00h C = 1 Z = 1 ; result is zero N = 0 | ||||
Example 3: |
| |||
Before
Instruction REG = 03h (0000 0011) W = 0Eh (0000 1110) C = 1 After Instruction REG = F5h (1111 0101) ; [two’s complement] W = 0Eh (0000 1110) C = 0 Z = 0 N = 1 ; result is negative |
SWAPF | Swap f | |||
---|---|---|---|---|
Syntax: | SWAPF f {,d {,a}} | |||
Operands: | 0 ≤ f ≤ 255 d ∈ [0,1] a ∈ [0,1] | |||
Operation: | (f<3:0>) → dest<7:4>, (f<7:4>) → dest<3:0> | |||
Status Affected: | None | |||
Encoding: | 0011 | 10da | ffff | ffff |
Description: | The upper and lower nibbles of register ‘f’ are exchanged. If ‘d’ is
‘0 ’, the result is placed in W. If ‘d’ is
‘1 ’, the result is placed in register ‘f’ (default).If ‘a’ is ‘ If ‘a’ is ‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write to destination |
Example: |
|
| ||
Before Instruction REG = 53h After Instruction REG = 35h |
TBLRD | Table Read | |||
---|---|---|---|---|
Syntax: | TBLRD ( *; *+; *-; +*) | |||
Operands: | None | |||
Operation: | if TBLRD *, (Prog Mem (TBLPTR)) → TABLAT; TBLPTR – No Change; if TBLRD *+, (Prog Mem (TBLPTR)) → TABLAT; (TBLPTR) + 1 → TBLPTR; if TBLRD *-, (Prog Mem (TBLPTR)) → TABLAT; (TBLPTR) – 1 → TBLPTR; if TBLRD +*, (TBLPTR) + 1 → TBLPTR; (Prog Mem (TBLPTR)) → TABLAT; | |||
Status Affected: | None | |||
Encoding: | 0000 | 0000 | 0000 | 10nn nn=0 * =1 *+ =2 *- =3 +* |
Description: | This instruction is used to read the contents of Program Memory
(P.M.). To address the program memory, a pointer called Table Pointer (TBLPTR)
is used. The TBLPTR (a 21-bit pointer) points to each byte in the program memory. TBLPTR has a 2-Mbyte address range. TBLPTR[0] = TBLPTR[0] =
The TBLRD instruction can modify the value of TBLPTR as follows:
| |||
Words: | 1 | |||
Cycles: | 2 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | No operation | No operation | No operation | |
No operation | No operation (Read Program Memory) | No operation | No operation (Write TABLAT) |
TBLRD | Table Read (Continued) | |||
Example1: |
| |||
Before Instruction TABLAT = 55h TBLPTR = 00A356h MEMORY (00A356h) = 34h After Instruction TABLAT = 34h TBLPTR = 00A357h | ||||
Example2: |
| |||
Before Instruction TABLAT = AAh TBLPTR = 01A357h MEMORY (01A357h) = 12h MEMORY (01A358h) = 34h After Instruction TABLAT = 34h TBLPTR = 01A358h |
TBLWT (Continued) | Table Write | |||
---|---|---|---|---|
Syntax: | TBLWT ( *; *+; *-; +*) | |||
Operands: | None | |||
Operation: | if TBLWT*, (TABLAT) → Holding Register; TBLPTR – No Change; if TBLWT*+, (TABLAT) → Holding Register; (TBLPTR) + 1 → TBLPTR; if TBLWT*-, (TABLAT) → Holding Register; (TBLPTR) – 1 → TBLPTR; if TBLWT+*, (TBLPTR) + 1 → TBLPTR; (TABLAT) → Holding Register; | |||
Status Affected: | None | |||
Encoding: | 0000 | 0000 | 0000 | 11nn nn=0 * =1 *+ =2 *- =3 +* |
Description: | This instruction uses the LSBs of TBLPTR to determine which of the
holding registers the TABLAT is written to. The holding registers are used to
program the contents of Program Memory (P.M.). Refer to the “Program Flash
Memory” section for additional details on programming Flash memory. The TBLPTR (a 21-bit pointer) points to each byte in the program memory. TBLPTR has a 2-MByte address range. The LSb of the TBLPTR selects which byte of the program memory location to access. TBLPTR[0] = TBLPTR[0] =
The TBLWT instruction can modify the value of TBLPTR as follows:
| |||
Words: | 1 | |||
Cycles: | 2 | |||
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | No operation | No operation | No operation | |
No operation | No operation (Read TABLAT) | No operation | No operation (Write to Holding Register ) |
TBLWT | Table Write (Continued) | |||
Example1: | TBLWT *+; | |||
Before Instruction TABLAT = 55h TBLPTR = 00A356h HOLDING REGISTER (00A356h) = FFh After Instructions (table write completion) TABLAT = 55h TBLPTR = 00A357h HOLDING REGISTER (00A356h) = 55h | ||||
Example 2: | TBLWT +*; | |||
Before Instruction TABLAT = 34h TBLPTR = 01389Ah HOLDING REGISTER (01389Ah) = FFh HOLDING REGISTER (01389Bh) = FFh After Instruction (table write completion) TABLAT = 34h TBLPTR = 01389Bh HOLDING REGISTER (01389Ah) = FFh HOLDING REGISTER (01389Bh) = 34h | ||||
TSTFSZ | Test f, skip if 0 | |||
---|---|---|---|---|
Syntax: | TSTFSZ f {,a} | |||
Operands: | 0 ≤ f ≤ 255 a ∈ [0,1] | |||
Operation: | skip if f = 0 | |||
Status Affected: | None | |||
Encoding: | 0110 | 011a | ffff | ffff |
Description: | If ‘f’ = 0, the next instruction fetched during the current instruction
execution is discarded and a NOP is executed, making this a
two-cycle instruction.If ‘a’ is ‘ If ‘a’ is
‘ | |||
Words: | 1 | |||
Cycles: | 1(2) Note: Three cycles if skip and followed by a two-word instruction. |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | No operation |
If skip: | ||||
Q1 | Q2 | Q3 | Q4 | |
No operation | No operation | No operation | No operation | |
If skip and followed by two-word instruction: | ||||
Q1 | Q2 | Q3 | Q4 | |
No operation | No operation | No operation | No operation | |
No operation | No operation | No operation | No operation |
Example: |
| |||
Before Instruction PC = Address (HERE) After Instruction If CNT = 00h, PC = Address (ZERO) If CNT ≠ 00h, PC = Address (NZERO) |
XORLW | Exclusive OR literal with W | |||
---|---|---|---|---|
Syntax: | XORLW k | |||
Operands: | 0 ≤ k ≤ 255 | |||
Operation: | (W) .XOR. k → | |||
Status Affected: | N, Z | |||
Encoding: | 0000 | 1010 | kkkk | kkkk |
Description: | The contents of W are XORed with the 8-bit literal ‘k’. The result is placed in W. | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read literal ‘k’ | Process Data | Write to W |
Example: | XORLW | 0AFh | ||
Before Instruction W = B5h After Instruction W = 1Ah |
XORWF | Exclusive OR W with f | |||
---|---|---|---|---|
Syntax: | XORWF f {,d {,a}} | |||
Operands: | 0 ≤ f ≤ 255 d ∈ [0,1] a ∈ [0,1] | |||
Operation: | (W) .XOR. (f) → dest | |||
Status Affected: | N, Z | |||
Encoding: | 0001 | 10da | ffff | ffff |
Description: | Exclusive OR the contents of W with register ‘f’. If ‘d’ is
‘0 ’, the result is stored in W. If ‘d’ is
‘1 ’, the result is stored back in the register ‘f’
(default).If ‘a’ is ‘ If ‘a’ is
‘ | |||
Words: | 1 | |||
Cycles: | 1 |
Q Cycle Activity: | ||||
Q1 | Q2 | Q3 | Q4 | |
Decode | Read register ‘f’ | Process Data | Write to destination |
Example: |
| |||
Before Instruction REG = AFh W = B5h After Instruction REG = 1Ah W = B5h |