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Hex Code in:
Binary Mode = [Encoding]
Source Mode = [Encoding]
Operation:
CLR
(CY) ← 0
CLR bit
Binary Mode
Bytes:
States:
†If this instruction addresses a port (P x , x = 0–3), add 2 states.
[Encoding]
1 0 1 0
1 0 0 1
Hex Code in:
Binary Mode = [A5][Encoding]
Source Mode = [Encoding]
Operation:
CLR
(bit) ← 0
CMP <dest>,<src>
Function:
Compare
Description:
Subtracts the source operand from the destination operand. The result is not stored in the
destination operand. If a borrow is needed for bit 7, the CY (borrow) flag is set; otherwise it is
clear.
When subtracting signed integers, the OV flag indicates a negative result when a negative
value is subtracted from a positive value, or a positive result when a positive value is
subtracted from a negative value.
Bit 7 in this description refers to the most significant byte of the operand (8, 16, or 32 bit)
The source operand allows four addressing modes: register, direct, immediate and indirect.
Flags:
CY
Example:
Register 1 contains 0C9H (11001001B) and register 0 contains 54H (01010100B). The
instruction
CMP R1,R0
clears the CY and AC flags and sets the OV flag.
Variations
CMP Rmd,Rms
Binary Mode
Bytes:
States:
Source Mode
4
4
4†
3†
1 1 0 0
AC
Source Mode
3
2
2
1
INSTRUCTION SET REFERENCE
0
y y y
OV
N
dir addr
Z
A-45
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