DE_Times_BC

DE_Times_BC:
;Inputs:
;     DE and BC are factors
;Outputs:
;     A is 0
;     BC is not changed
;     DEHL is the product
;
       ld hl,0
       ld a,16
Mul_Loop_1:
         add hl,hl
         rl e \ rl d
         jr nc,$+4
           add hl,bc
           inc de
         dec a
         jr nz,Mul_Loop_1
       ret