Intel mcs-48 Contents of the accumulator are cleared to zero, Flag 1 is cleared to zero F1-0

Models: mcs-48

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INSTRUCTION SET

CLR A Clear Accumulator

10010101111

The contents of the accumulator are cleared to zero.

A.-O

CLR C Clear Carry Bit

11001101111

During normal program execution, the carry bit can

be set to one by the ADD, ADDC, RLC, CPL C, RRC, and DAA instructions. This instruction resets the carry bit to zero.

C.-O

CLR F1 Clear Flag 1 (Not in 8021,8022)

11010 101011

Flag 1 is cleared to zero.

(F1)'-0

CLR FO Clear Flag 0 (Not in 8021, 8022)

11 00 0 101011

Flag 0 is cleared to zero.

(FO).- 0

CPL A Complement Accumulator

10011101111

The contents of the accumulator are complemented. This is strictly a one'scomplement. Each one is changed to zero and vice-versa.

(A).- NOT (A)

Example: Assume accumulator contains 01101010.

CPLA: CPL A;ACC CONTENTS ARE COMPLE- ;MENTED TO 10010101

CPL C Complement Carry Bit

11010 101111

The setting of the carry bit is complemented; one is changed to zero, and zero is changed to one.

(C).- NOT (C)

Example: Set C to one; current setting is unknown.

CT01: CLR C;C IS CLEARED TO ZERO

CPL C;C IS SET TO ONE

Mnemonics copyright Intel Corporation 1976.

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Intel mcs-48 manual Contents of the accumulator are cleared to zero, Flag 1 is cleared to zero F1-0