D-61
API
Mnemonic
Operands
Function
21 SUB
P
S
1
, S
2
,
D Subtraction
Type
OP
Bit Devices
Word devices
Program Steps
X
Y
M K
H KnX KnY KnM T C D SUB, SUBP: 7 steps
DSUB, DSUBP: 13 steps
S
1
*
*
*
*
*
*
*
*
S
2
*
*
*
*
*
*
*
*
D
*
*
*
*
*
Operands:
S1: Minuend S2: Subtrahend D: Remainder
Explanations:
1.
This instruction subtracts S1 and S2 in BIN format and stores the result in D.
2.
The highest bit is symbolic bit 0 (+) and 1 (-), which is suitable for algebraic subtraction.
3.
Flag changes in binary subtraction
In 16-bit instruction:
A. If the operation result
＝
0, zero flag M1020 = On.
B. If the operation result
＜
-32,768, borrow flag M1021 = On.
C. If the operation result
＞
32,767, carry flag M1022 = On.
Program Example:
In 16-bit BIN subtraction:
When X0 = On, the content in D0 will minus the content in D10 and the remainder will be stored in
D20.
X0
SUB
D0
D10
D20
