STMicroelectronics ST10 Series Programming Manual page 120

ST10 FAMILY PROGRAMMING MANUAL
SUBC
Syntax
Operation
Data Types
Description
Performs a 2's complement binary subtraction of the source operand specified by op2 and the previously
generated carry bit from the destination operand specified by op1. The result is then stored in op1. This
instruction can be used to perform multiple precision arithmetic.
Flags
E
*
E Set if the value of op2 represents the lowest possible negative number. Cleared otherwise.
Used to signal the end of a table.
Z Set if result equals zero and the previous Z flag was set. Cleared otherwise.
V Set if an arithmetic underflow occurred, i.e. the result cannot be represented in the specified
data type. Cleared otherwise.
C Set if a borrow is generated. Cleared otherwise.
N Set if the most significant bit of the result is set. Cleared otherwise.
Addressing Modes
Mnemonic
SUBC
SUBC
SUBC
SUBC
SUBC
SUBC
SUBC
118/172
Integer Subtraction with Carry
SUBC
(op1)
WORD
Z
S
Rw
, Rw
n m
Rw , [Rw ]
n i
Rw , [Rw +]
n i
Rw , #data
n 3
reg, #data
16
reg, mem
mem, reg
op1, op2
<-- (op1) - (op2) - (C)
V
*
Format
30 nm
38 n:10ii
38 n:11ii
38 n:0###
36 RR ## ##
32 RR MM MM
34 RR MM MM
C N
S *
Bytes
2
2
2
2
4
4
4