SBC
Sum of second operand and carry flag is subtracted from the first operand. Results are written into the first operand.
Syntax
sbc a,op8 ;8 bits
sbc hl,op16 ;16 bits
Allowed Instructions
sbc a,a
sbc a,b
sbc a,c
sbc a,d
sbc a,e
sbc a,h
sbc a,l
sbc a,ixh
sbc a,ixl
sbc a,iyh
sbc a,iyl
sbc a,(hl)
sbc a,(ix+n)
sbc a,(iy+n)
sbc a,n ;8 bits
sbc hl,bc
sbc hl,de
sbc hl,hl
sbc hl,sp
Effects
N flag is set, P/V detects overflow, rest modified by definition.
In the case of 16-bit registers, h flag is undefined.
Uses
Multiple precision subtraction
T-States
r denotes 8-bit register.
rr represents a two byte register pair: BC, DE, HL, SP
r | 4 |
X | 7 |
(hl) | 7 |
(ix+X) | 19 |
(iy+X) | 19 |
hl, rr | 15 |
See Also
page revision: 7, last edited: 31 Oct 2014 13:31