TENX TECHNOLOGY TM57PA20, User Manual

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Advance Information UM-TM57PA20&40_E
8 Bit Microcontroller
32
tenx technology, inc.
Preliminary
Rev 1.3, 2009/10/19
COMF Complement “f”
Syntax COMF f [,d]
Operands f : 00h ~ 7Fh, d : 0, 1
Operation
(destination) ← (f
_
)
Status Affected Z
OP-Code 00 1001 dfff 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’.
Cycle 1
Example COMF
REG1,0 B : REG1 = 0x13
A : REG1 = 0x13, W = 0xEC
DECF Decrement “f”
Syntax DECF f [,d]
Operands f : 00h ~ 7Fh, d : 0, 1
Operation (destination) ← (f) - 1
Status Affected Z
OP-Code 00 0011 dfff ffff
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’.
Cycle 1
Example DECF
CNT, 1 B : CNT = 0x01, Z = 0
A : CNT = 0x00, Z = 1
DECFSZ Decrement “f”, Skip if 0
Syntax DECFSZ f [,d]
Operands f : 00h ~ 7Fh, d : 0, 1
Operation (destination) ← (f) - 1, skip next instruction if result is 0
Status Affected -
OP-Code 00 1011 dfff ffff
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 1, the next instruction is executed. If the result is 0, then a NOP is
executed instead, making it a 2 cycle instruction.
Cycle 1 or 2
Example LABEL1 DECFSZ CNT, 1
GOTO LOOP
CONTINUE
B : PC = LABEL1
A : CNT = CNT – 1
if CNT=0, PC = CONTINUE
if CNT
≠ 0, PC = 1
GOTO Unconditional Branch
Syntax GOTO k
Operands k : 00h ~ 7FFh
Operation PC.11~0 ← k
Status Affected -
OP-Code 11 kkkk kkkk kkkk
Description GOTO is an unconditional branch. The 12-bit immediate value is loaded
into PC bits <11:0>. GOTO is a two-cycle instruction.
Cycle 2
Example
LABEL1 GOTO SUB1
B : PC = LABEL1
A : PC = SUB1