z00m's speccy knowledge base

downhl	inc h
        ld a,h
        and 7
        ret nz
        ld a,l
        add a,#20
        ld l,a
        ret c
        ld a,h
        sub 8
        ld h,a
        ret

Slower alternative:

downhl    inc  h                 
          ld   a,h               
          and  7                 
          ret  nz                
          ld   a,l               
          add  a,32              
          ld   l,a               
          ld   a,h               
          jr   c,downhl2         
          sub  8                 
          ld   h,a               
downhl2   cp   88                
          ret  c                 
          ld   h,64              
          ret

Navigation: general . math . graphic . sound . system . other . back to start