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- inloc = tempword1
- incnt = tempword2
- zlz_decomp:
- ;Input:
- ; HL points to the zlz compressed data
- ; DE points to the output stream
- ; BC is the size of the data
- ;Notes:
- ; While the format that this accepts uses arbitrary numbers of bits for
- ; sizes and offsets, this Z80 algorithm only works on 13-bit or 14-bit
- ; values (context dependent)
- ;
- ld a,(hl)
- inc hl
- add a,a
- ld (incnt),bc
- jr c,cpindex
- ;from here, read the size in, then copy the data
- add a,a
- ld b,0
- ld c,a
- jr nc,+_
- ld a,(hl)
- inc hl
- add a,a
- ret c
- rrca
- ld b,a
- call deccnt
- _:
- srl b
- rr c
- srl b
- rr c
- push hl
- ld hl,(incnt)
- sbc hl,bc
- ld (incnt),hl
- pop hl
- ldir
- dec hl
- ld bc,(incnt)
- cpi
- jp pe,zlz_decomp
- ret
- cpindex:
- add a,a
- ld b,0
- ld c,a
- jr nc,+_
- ld a,(hl)
- inc hl
- add a,a
- ret c
- rrca
- ld b,a
- call deccnt
- _:
- srl b
- rr c
- srl b
- rr c
- ;BC is the new size
- ;Now we need to grab the index
- push bc
- ld a,(hl)
- add a,a
- ld b,0
- ld c,a
- jr nc,+_
- inc hl
- ld a,(hl)
- add a,a
- jp c,pop_exit
- rrca
- ld b,a
- call deccnt
- _:
- srl b
- rr c
- ld (inloc),hl
- ld h,d
- ld l,e
- or a
- sbc hl,bc
- pop bc
- ldir
- ld hl,(inloc)
- ld bc,(incnt)
- dec bc
- cpi
- jp pe,zlz_decomp
- ret
- deccnt:
- push hl
- ld hl,(incnt)
- dec hl
- ld (incnt),hl
- pop_exit:
- pop hl
- ret
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