;---------------------------------------------------------------------
; Routine:      BCDToNumber
; Arguments:    a - a number in BCD (e.g. hex $19 = dec 19)
; Returns:      a - converted number
; Alters:       af
;---------------------------------------------------------------------
BCDToNumber:
        push    bc
        push    hl

        ;convert back to normal with:
        ;  a = a[7:4] * 10 + a[3:0]
        ld      b,a                     ;save A
        swap    a
        and     %00001111
        ld      hl,.lookupTimes10
        add     l
        ld      l,a
        ld      a,0
        adc     h
        ld      h,a
        ld      a,[hl]                  ;Upper nibble times 10
        ld      c,a
        ld      a,b
        and     %00001111
        add     c

        pop     hl
        pop     bc
        ret

.lookupTimes10
        DB  0,10,20,30,40,50,60,70,80,90