up:     djnz    r7,up1
        djnz    r6,up1
        ret
up1:    movx    a,@dptr          ;We move the data in up direction
        inc     dptr
        mov     store,r4         ;Swap r4,dph
        mov     r4,dph
        mov     dph,store
        mov     store,r5         ;Meant to swap r5,dpl I guess
        mov     r4,dpl
        mov     dpl,r5
        movx    @dptr,a
        inc     dptr
        sjmp    up