Zilog Z8F0130 - Manual (Page 250)

eZ8
™
CPU Core
User Manual
UM012820-0810 SUBX Instruction
235
SUBX
Definition
Subtract using Extended Addressing.
Syntax
SUBX dst, src
Operation
dst
 dst - src
Description
This new eZ8 extended addressing instruction subtracts the source oper-
and from the destination operand. The destination operand stores the
result. The source operand contents are unaffected. The eZ8 CPU per-
forms subtraction by adding the two’s complement of the source operand
to the destination operand.
Flags
C Set if a borrow is required by bit 7; reset otherwise
Z Set if the result is zero; reset otherwise
S Set if the result is negative; reset otherwise
V Set if an arithmetic overflow occurs; reset otherwise
D Set to 1
H Set if a borrow is required by bit 3; reset otherwise