D-62
API
Mnemonic
Operands Function
22 MUL P S
1
, S
2
,
D Multiplication
Type
OP
Bit Devices
Word devices
Program Steps
X
Y
M K
H KnX KnY KnM T C D MUL, DMULP: 7 steps
S
1
*
*
*
*
*
*
*
*
S
2
*
*
*
*
*
*
*
*
D
*
*
*
*
*
Operands:
S1: Multiplicand S2: Multiplicator D: Product
Explanations:
1.
In 16-bit instruction, D occupies 2 consecutive devices.
2.
This instruction multiplies S1 by S2 in BIN format and stores the result in D. Be careful
with the positive/negative signs of S1, S2 and D when doing 16-bit and 32-bit operations.
16-bit command:
S1
D
b15..........b0
X
b15..........b0
S2
=
b31..........b16b15..............b0
D
+1
b15 is a symbol bit
b15 is a symbol bit
b31 is a symbol bit (b15 of D+1)
Symbol bit = 0 refers to a positive value.
Symbol bit = 1 refers to a negative value.
When D serves as a bit device, it can designate K1 ~ K4 and construct a 16-bit result, occupying
consecutive 2 groups of 16-bit data.
Program Example:
The 16-bit D0 is multiplied by the 16-bit D10 and brings forth a 32-bit product. The higher 16 bits are
stored in D21 and the lower 16-bit are stored in D20. On/Off of the most left bit indicates the
positive/negative status of the result value.
X0
D0
D10
D20
MUL
