8052 Instruction Set

CPL

Complement Register

 

 

 

Syntax

CPL operand

 

 

 

 

 

 

 

 

 

 

 

Instructions

OpCode

Bytes

Cycles

Flags

 

 

 

 

 

 

 

CPL A

0xF4

1

1

None

 

 

 

 

 

 

 

CPL C

0xB3

1

1

C

 

 

 

 

 

 

 

CPL bitAddr

0xB2

2

1

None

 

 

 

 

 

 

CPL complements operand, leaving the result in operand. If operand is a single bit, the state of the bit is reversed. If operand is the accumulator, all the bits in the accumulator are reversed. This can be thought of as accumulator logical exclusive OR 255, or as 255-accumulator. If operand refers to a bit of an output port, the value complemented is based on the last value written to that bit, not the last value read from it.

See also: CLR, SETB

DA

Decimal Adjust Accumulator

 

 

 

Syntax

DA A

 

 

 

 

 

 

 

 

 

 

 

Instructions

OpCode

Bytes

Cycles

Flags

 

 

 

 

 

 

 

DA A

0xD4

1

1

C

 

 

 

 

 

 

DA adjusts the contents of the accumulator to correspond to a BCD (binary coded decimal) number after two BCD numbers have been added by the ADD or ADDC instruction.

If the carry bit is set or if the value of bits 0−3 exceed 9, 0x06 is added to the accumulator. If the carry bit was set when the instruction began, or if 0x06 was added to the accumulator in the first step, 0x60 is added to the accumulator.

The carry (C) bit is set if the resulting value is greater than 0x99. Otherwise, it is cleared.

See also: ADD, ADDC

E-8

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Texas Instruments MSC1210 manual Cpl, Complement Register, Decimal Adjust Accumulator, CPL operand, 0xD4