BC_Div_DE (Size+Speed Optimized).

;===============================================================
BC_Div_DE:
;===============================================================
;Performs BC/DE
;Speed:   1130+6b cycles
;Size:    27 bytes
;Inputs:
;     BC is the numerator
;     DE is the denominator
;Outputs:
;     BC is the quotient
;     HL is the remainder
;     DE is not changed
;     A is 0
;     z flag is set
;     c flag is reset
;===============================================================
    ld a,b
    ld hl,0
    ld b,16
loop:
    rl c
    rla
    adc hl,hl
    sbc hl,de
    jr nc,$+3
    add hl,de
    djnz loop
    rl c
    rla
    cpl
    ld b,a
    ld a,c
    cpl
    ld c,a
    ret