Oki MSM85C154HVS - Page 285

MSM80C154S/83C154S/85C154HVS
278
29. DA A (Decimal adjust accumulator)
11010100
70
Instruction code
Operations
Number of bytes
Number of cycles
Flags
(PSW)
Description
: Byte 1
10
1
+6
(C)←1
:
C AC F0 RS1 RS0 OV F1 P
••
:
:
:
The arithmetic operation result located in the accumulator
following an addition between two 2-digit decimal number is
converted to a normal decimal number. When the contents of
accumulator bits 0 thru 3 (10
0
digit) are greater than 9, or when
the auxiliary carry (AC) is 1, 6 is added to accumulator bits 0
thru 3. And if the contents of accumulator bits 4 thru 7 (10
1
digit)
exceed 9, or if the result obtained by adding a carry from the
lower order digits after compensation is greater than 9, or if the
carry flag is 1, 6 is added to the data in accumulator bits 4 thru
7. The flags are also updated.
:
1
1
10
0
+6←(AC)=1 or 10
0
>10
←(C)=1 or 10
1
>10
}