Programming:Integer Division
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8bit division
Input: HL=Value1, C=Value2
Output: L=Value1/Value2, H=Value1 MOD Value2
Destroyed: AF,BC
LD B,8
Div_Next:
ADD HL,HL
LD A,H
SUB C
JR C,Div_NXTB
LD H,A
INC L
Div_NXTB:
DJNZ Div_Next
RET
16bit division
Input: BC=Value1, DE=Value2
Output: HL=Value1/Value2, DE=Value1 MOD Value2
Destroyed: AF,BC
clcd16 ld a,e
or d
ld hl,0
ret z
ld a,b
ld b,16
clcd161 rl c
rla
adc hl,hl
sbc hl,de
jr nc,clcd162
add hl,de
clcd162 ccf
djnz clcd161
ex de,hl
rl c
rla
ld h,a
ld l,c
ret
24bit division
Input: A,BC=Value1, DE=Value2
Output: HL=Value1/Value2, DE=Value1 MOD Value2
Destroyed: AF,BC,IX,IYL
clcdiv db #dd:ld l,e
db #dd:ld h,d ;IX=Value2
ld e,a ;E,BC=Value1(Counter)
ld hl,0
db #dd:ld a,l
db #dd:or h
ret z
ld d,l ;D,HL=CalcVar
db #fd:ld l,24 ;IYL=Counter
clcdiv1 rl c
rl b
rl e
rl l
rl h
rl d
ld a,l
db #dd:sub l
ld l,a
ld a,h
db #dd:sbc h
ld h,a
ld a,d
sbc 0
ld d,a ;D,HL=D,HL-IX
jr nc,clcdiv2
ld a,l
db #dd:add l
ld l,a
ld a,h
db #dd:adc h
ld h,a
ld a,d
adc 0
ld d,a
scf
clcdiv2 ccf
db #fd:dec l
jr nz,clcdiv1
ex de,hl ;DE=Value1 MOD Value2
rl c
rl b
ld l,c
ld h,b ;HL=Value1 DIV Value2
ret
32bit division
Input: IY,BC=Value1, IX=Value2
Output: IY,BC=Value1/Value2, HL=Value1 MOD Value2
Destroyed: AF,DE,IY
clcd32c db 0
clcd32 ld hl,0
db #dd:ld a,l
db #dd:or h
ret z ;IY,BC=Value1(Counter)
ld de,0 ;DE,HL=CalcVar
ld a,32 ;Set Counter to 32
clcd321 ld (clcd32c),a
rl c
rl b
db #fd:ld a,l:rla:db #fd:ld l,a
db #fd:ld a,h:rla:db #fd:ld h,a
rl l
rl h
rl e
rl d
ld a,l
db #dd:sub l
ld l,a
ld a,h
db #dd:sbc h
ld h,a
ld a,e
sbc 0
ld e,a
ld a,d
sbc 0
ld d,a
jr nc,clcd322
ld a,l
db #dd:add l
ld l,a
ld a,h
db #dd:adc h
ld h,a
ld a,e
adc 0
ld e,a
ld a,d
adc 0
ld d,a
scf
clcd322 ccf
ld a,(clcd32c)
dec a
jr nz,clcd321 ;HL=Value1 MOD Value2
rl c
rl b
db #fd:ld a,l:rla:db #fd:ld l,a
db #fd:ld a,h:rla:db #fd:ld h,a
ret ;IY,BC=Value1 DIV Value2
