Difference between revisions of "TRACKERS MB SRC EN SNGDECR"
From MSX MUSIC WIKI
(Created page with ";--- MoonBlaster song decruncher --- ; ; Storage of song data: Only zeros crunched. ; All values above 242 = 1 or more zeros, so max. 13 sngdecrc: ld a,sngpag ; SNGPAG = ma...") |
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| − | ;--- MoonBlaster song decruncher --- | + | ;--- MoonBlaster song decruncher --- |
| − | ; | + | ; |
| − | ; Storage of song data: Only zeros crunched. | + | ; Storage of song data: Only zeros crunched. |
| − | ; All values above 242 = 1 or more zeros, so max. 13 | + | ; All values above 242 = 1 or more zeros, so max. 13 |
| − | + | ||
| − | + | ||
| − | sngdecrc: ld a,sngpag ; SNGPAG = mapperbank with ONGECRUNCHTE | + | sngdecrc: ld a,sngpag ; SNGPAG = mapperbank with ONGECRUNCHTE |
| − | + | out (0feh),a ; songdata | |
| − | + | ||
| − | + | ld hl,08000h ; move the settings | |
| − | + | ld de,08000h+200 | |
| − | + | ld bc,376 ; number of bytes v. div. settings | |
| − | sngdecrl1: call copybyte | + | sngdecrl1: call copybyte |
| − | + | inc hl | |
| − | + | inc de | |
| − | + | dec bc | |
| − | + | ld a,b | |
| − | + | or c | |
| − | + | jr nz,sngdecrl1 | |
| − | + | ||
| − | + | ld a,em1pag ; EM1PAG = mapperbank with GECRUNCHTE | |
| − | + | out (0feh),a ; songdata | |
| − | + | ld a,(08000h) ; last position | |
| − | + | inc a | |
| − | + | ld b,a | |
| − | + | push bc ; move pat/pos data | |
| − | + | ld de,08000h | |
| − | sngdecrl2: call copybyte | + | sngdecrl2: call copybyte |
| − | + | inc hl | |
| − | + | inc de | |
| − | + | djnz sngdecrl2 | |
| − | + | pop bc | |
| − | + | ||
| − | + | push hl | |
| − | + | ld e,1 | |
| − | + | ld hl,08000h | |
| − | sngdecrl3: ld a,(hl) | + | sngdecrl3: ld a,(hl) |
| − | + | cp e | |
| − | + | jr c,sngdecrl4 | |
| − | + | ld e,a | |
| − | sngdecrl4: inc hl | + | sngdecrl4: inc hl |
| − | + | djnz sngdecrl3 | |
| − | + | ||
| − | + | ld d,0 | |
| − | + | pop hl | |
| − | + | add hl,de | |
| − | + | add hl,de ; skip pattern adress | |
| − | + | ||
| − | + | ld a,em1pag | |
| − | + | out (0feh),a | |
| − | + | ||
| − | + | ld de,08240h ; real decreases of song data | |
| − | + | ld bc,03dc0h ; !maximale! number of bytes | |
| − | sngdecrl6: ld a,(hl) | + | sngdecrl6: ld a,(hl) |
| − | + | or a | |
| − | + | jr z,sngdecrend ; found an end marker? gone earlier! | |
| − | + | cp 243 | |
| − | + | jr nc,sngdecrl7 ; crunched data? then decrease! | |
| − | + | call wrtbyte | |
| − | sngdecrl9: inc hl | + | sngdecrl9: inc hl |
| − | + | dec bc | |
| − | + | ld a,b | |
| − | + | or c | |
| − | + | jr nz,sngdecrl6 | |
| − | sngdecrend: ld a,sngpag ; end of decrunch | + | sngdecrend: ld a,sngpag ; end of decrunch |
| − | + | out (0feh),a | |
| − | + | ret | |
| − | + | ||
| − | sngdecrl7: push bc ; decreasing series zeros | + | sngdecrl7: push bc ; decreasing series zeros |
| − | + | sub 242 | |
| − | + | ld b,a | |
| − | sngdecrl8: xor a | + | sngdecrl8: xor a |
| − | + | call wrtbyte | |
| − | + | djnz sngdecrl8 | |
| − | + | pop bc | |
| − | + | jr sngdecrl9 | |
| − | + | ||
| − | + | ||
| − | + | ||
| − | ;--- copy data byte from one mapper bank to another --- | + | ;--- copy data byte from one mapper bank to another --- |
| − | + | ||
| − | copybyte: ld a,em1pag | + | copybyte: ld a,em1pag |
| − | + | out (0feh),a | |
| − | + | ld a,(hl) | |
| − | + | ex af,af' | |
| − | + | ld a,sngpag | |
| − | + | out (0feh),a | |
| − | + | ex af,af' | |
| − | + | ld (de),a | |
| − | + | ret | |
| − | + | ||
| − | ;--- write decrunched databyte --- | + | ;--- write decrunched databyte --- |
| − | + | ||
| − | wrtbyte: ex af,af' | + | wrtbyte: ex af,af' |
| − | + | ld a,sngpag | |
| − | + | out (0feh),a | |
| − | + | ex af,af' | |
| − | + | ld (de),a | |
| − | + | ld a,em1pag | |
| − | + | out (0feh),a | |
| − | + | inc de | |
| − | + | ret | |
| − | + | ||
| − | ������������������������������������������������������������������������������������������������������������������ | + | ������������������������������������������������������������������������������������������������������������������ |
Latest revision as of 08:24, 17 July 2019
;--- MoonBlaster song decruncher ---
;
; Storage of song data: Only zeros crunched.
; All values above 242 = 1 or more zeros, so max. 13
sngdecrc: ld a,sngpag ; SNGPAG = mapperbank with ONGECRUNCHTE
out (0feh),a ; songdata
ld hl,08000h ; move the settings
ld de,08000h+200
ld bc,376 ; number of bytes v. div. settings
sngdecrl1: call copybyte
inc hl
inc de
dec bc
ld a,b
or c
jr nz,sngdecrl1
ld a,em1pag ; EM1PAG = mapperbank with GECRUNCHTE
out (0feh),a ; songdata
ld a,(08000h) ; last position
inc a
ld b,a
push bc ; move pat/pos data
ld de,08000h
sngdecrl2: call copybyte
inc hl
inc de
djnz sngdecrl2
pop bc
push hl
ld e,1
ld hl,08000h
sngdecrl3: ld a,(hl)
cp e
jr c,sngdecrl4
ld e,a
sngdecrl4: inc hl
djnz sngdecrl3
ld d,0
pop hl
add hl,de
add hl,de ; skip pattern adress
ld a,em1pag
out (0feh),a
ld de,08240h ; real decreases of song data
ld bc,03dc0h ; !maximale! number of bytes
sngdecrl6: ld a,(hl)
or a
jr z,sngdecrend ; found an end marker? gone earlier!
cp 243
jr nc,sngdecrl7 ; crunched data? then decrease!
call wrtbyte
sngdecrl9: inc hl
dec bc
ld a,b
or c
jr nz,sngdecrl6
sngdecrend: ld a,sngpag ; end of decrunch
out (0feh),a
ret
sngdecrl7: push bc ; decreasing series zeros
sub 242
ld b,a
sngdecrl8: xor a
call wrtbyte
djnz sngdecrl8
pop bc
jr sngdecrl9
;--- copy data byte from one mapper bank to another ---
copybyte: ld a,em1pag
out (0feh),a
ld a,(hl)
ex af,af'
ld a,sngpag
out (0feh),a
ex af,af'
ld (de),a
ret
;--- write decrunched databyte ---
wrtbyte: ex af,af'
ld a,sngpag
out (0feh),a
ex af,af'
ld (de),a
ld a,em1pag
out (0feh),a
inc de
ret
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