MSM80C154S/83C154S/85C154HVS
360
100. SUBB A, data address (Substract memory from accumulator with borrow)
10010100
70
Instruction code
Data address
Operation
Number of bytes
Number of cycles
Flags
(PSW)
Description
Example SUBB A, DPH
Instruction code
: Byte 1
a7 a6 a5 a4 a3 a2 a1 a0
70
Byte 2
(A)←(A)–((C)+(data address)):
C AC F0 RS1 RS0 OV F1 P
•• • •
:
:
:
The carry flag contents and the specified data address contents
are substracted from the accumulator contents. The result is
placed in the accumulator, and the flags are updated.
:
10010101
70
Byte 1
DPH
10101010
70
2
1
10000011
70
Byte 2
Before execution
DPH
10101010
70
After execution
:
0
Carry flag
1
Carry flag
0
Auxiliary carry flag
1
Auxiliary carry flag
0
Overflow flag
0
Overflow flag
Accumulator
01010101
70
Accumulator
10101011
70
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