ORA

 


Opcode

Operand

Description

ORA

R

M

Logical OR register or memory with

accumulator

 

 

—  The contents of the accumulator are logically ORed with the contents of the register or

memory.

 

—  The result is placed in the accumulator.

 

—  If the operand is a memory location, its address is specified by the contents of H-L pair.

 

—  S, Z, P are modified to reflect the result.

 

—  CY and AC are reset.

 

—  Example: ORA B or ORA M.

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