Re: A86: Super fast GridPutSprite


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Re: A86: Super fast GridPutSprite




In a message dated 11/3/98 5:17:40 PM Eastern Standard Time, electrum@tfs.net
writes:

> loaddata:
>   ld hl,mapvar-1    ; point to var name (first byte is irrelevant)
>   rst 20h     ; load name into OP1
>   rst 10h     ; call _FINDSYM
>   ret c       ; if it doesn't exist, return
>   ld a,b      ; copy high byte
>   ex de,hl     ; swap low bytes


>   inc hl      ; skip length word
>   inc hl      ; it is a word, not a byte...


instead of two inc hl's, use this instead:
 call $4c3f				;ahl += 2

that way, if there's a carry, it's accounted for in this one call.
if hl=$fffe or $ffff, there will be major problems when it wraps around using
your way.