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ORL
<dest-byte> <src-byte>
Function:
Logical OR for byte variables
Description:
ORL performs the bitwise logical OR operation between the indicated variables,
storing the results in the destination byte. No flags are affected .
The two operands allow six addressing mode combinations. When the destination
is the accumulator, the source can use register, direct, register-indirect, or
immediate addressing; when the destination is a direct address, the source can be
the accumulator or immediate data.
Note:
When this instruction is used to modify an output port, the value used as the original
port data will be read from the output data latch, not the input pins.
Example:
If the accumulator holds 0C3 H (11000011B) and R0 holds 55 H (01010101B) then
the instruction
ORL
will leave the accumulator holding the value 0D7 H (11010111B).
When the destination is a directly addressed byte, the instruction can set
combinations of bits in any RAM location or hardware register. The pattern of bits
to be set is determined by a mask byte, which may be either a constant data value
in the instruction or a variable computed in the accumulator at run-time. The
instruction
ORL
will set bits 5, 4, and 1 of output port 1.
ORL
A,Rn
Operation:
ORL
(A) ← (A) ∨ (Rn)
Encoding:
0 1 0 0
Bytes:
1
Cycles:
1
Semiconductor Group
A,R0
P1,#00110010B
1 r r r
*
186
Instruction Set
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