http://learn.cemetech.net/index.php?action=history&feed=atom&title=Z80%3AOpcodes%3AADD 2026-05-02T10:46:43Z Revision history for this page on the wiki MediaWiki 1.43.3 http://learn.cemetech.net/index.php?title=Z80:Opcodes:ADD&diff=266&oldid=prev 2016-02-05T22:05:24Z

<p>Initial automated import</p> <p><b>New page</b></p><div>The values of the two operands are added together, and the result is written back to the first one.<br /> <br /> == Syntax ==<br /> <br /> add a,op8 ;8 bits<br /> add op16,op16 ;16 bits<br /> <br /> === Allowed instructions ===<br /> <br /> add a,a<br /> add a,b<br /> add a,c<br /> add a,d<br /> add a,e<br /> add a,h<br /> add a,l<br /> add a,ixh<br /> add a,ixl<br /> add a,iyh<br /> add a,ixl<br /> add a,(hl)<br /> add a,(ix+n)<br /> add a,(iy+n)<br /> add a,n ;8-bit constant<br /> <br /> add hl,bc<br /> add hl,de<br /> add hl,hl<br /> add hl,sp<br /> <br /> add ix,bc<br /> add ix,de<br /> add ix,ix<br /> add ix,sp<br /> <br /> add iy,bc<br /> add iy,de<br /> add iy,iy<br /> add iy,sp<br /> <br /> == Effects ==<br /> <br /> === 8-bit arithmetic ===<br /> <br /> N flag is reset, P/V is interpreted as overflow.<br /> Rest of the flags is modified by definition.<br /> <br /> === 16-bit arithmetic ===<br /> <br /> preserves the S, Z and P/V flags, and H is undefined.<br /> Rest of flags modified by definition.<br /> <br /> == Uses ==<br /> <br /> Obviously used to add two numbers together. However, you can add 16-bit numbers to sp, giving you control of where the stack pointer is pointing to.<br /> <br /> == T-States ==<br /> r denotes 8-bit register.<br /> rr represents a two byte register pair: BC, DE, HL, SP<br /> {| class=&quot;wikitable&quot;<br /> | r || 4 <br /> |-<br /> | X || 7 <br /> |-<br /> | (hl) || 7 <br /> |-<br /> | (ix+X) || 19 <br /> |-<br /> | (iy+X) || 19 <br /> |-<br /> | hl, rr || 11 <br /> |-<br /> | ix, rr || 15 <br /> |-<br /> | iy, rr || 15 <br /> |}<br /> <br /> == See Also ==<br /> <br /> [[Z80:Opcodes:ADC|ADC]],[[Z80:Opcodes:DAA|DAA]],[[Z80:Opcodes:DEC|DEC]],[[Z80:Opcodes:INC|INC]],[[Z80:Opcodes:SBC|SBC]],[[Z80:Opcodes:SUB|SUB]]<br /> <br /> {{lowercase}}<br /> [[Category:Z80 Assembly]]<br /> [[Category:Z80 Heaven]]<br /> [[Category:Z80 Opcodes]]</div>

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