< %27
7UGT U /CPWCN
80
(OHYHQ E\WHV DUH UHTXLUHG IRU WKLV RSHUDWLRQ
)LJXUH
6KLIWLQJ RI %&' 'LJLWV%\WHV
([DPSOH )RXU
2QH QXPEHU LV WR EH VXEWUDFWHG IURP DQRWKHU QXPEHU ERWK RI ZKLFK DUH LQ
SDFNHG %&' IRUPDW DQG DUH RI HTXDO EXW YDU\LQJ OHQJWK 7KH UHVXOW LV VWRUHG
LQ WKH ORFDWLRQ RI WKH PLQXHQG 7KH RSHUDWLRQ LV SURJUDPPHG DV IROORZV
LD
HL, ARG1
LD
DE, ARG2
LD
B, LENGTH ;LENGTH OF TWO ARGUMENTS
AND
A
SUBDEC:LD
A, (DE)
SBC
A, (HL)
;B IS NOT ZERO, OTHERWISE FALL
;THROUGH.
0
;ADDRESS OF MINUEND
;ADDRESS OF SUBTRAHEND
;CLEAR CARRY FLAG
;SUBTRAHEND TO ACC
;SUBTRACT (HL) FROM ACC
+DUGZDUH DQG 6RIWZDUH ,PSOHPHQWDWLRQ ([DPSOHV
Need help?
Do you have a question about the Z80 and is the answer not in the manual?
Questions and answers