mirror of
https://github.com/deater/dos33fsprogs.git
synced 2024-12-26 11:30:12 +00:00
dya: more work on playing two tracks at once
This commit is contained in:
Vince Weaver
parent
6146f3a229
commit
f5c91a3097
@ -22,9 +22,8 @@ CHIPTUNE_PLAYER: chiptune_player.o
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ld65 -o CHIPTUNE_PLAYER chiptune_player.o -C ../linker_scripts/apple2_800.inc
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chiptune_player.o: chiptune_player.s \
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../asm_routines/mockingboard.s \
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../asm_routines/dos33_routines.s \
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../asm_routines/lz4_decode.s \
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mockingboard_a.s \
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lz4_decode.s \
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../asm_routines/keypress_minimal.s \
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rasterbars.s volume_bars.s interrupt_handler.s qkumba_rts.s \
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chip_title_uncompressed.inc zp.inc
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@ -2,10 +2,10 @@
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.include "zp.inc"
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; program is ~4k, so from 0xc00 to 0x1C00
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LZ4_BUFFER EQU $1C00 ; $1C00 - $5C00, 16k for now
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DISK_BUFFER EQU $5D00 ; for disk loading
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UNPACK_BUFFER EQU $6000 ; $6000 - $9800, 14k, $3800
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LZ4_BUFFER EQU $1C00 ; $1C00 - $4400, 10k = $2800
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DISK_BUFFER EQU $4400 ; for disk loading
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UNPACK_BUFFER1 EQU $5000 ; $5000 - $8800, 14k, $3800
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UNPACK_BUFFER2 EQU $8800 ; $8800 - $C000, 14k, $3800
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; by using qkumba's RTS code
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; no need for DOS, so we actually
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; are free the whole way to $C000
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@ -13,7 +13,7 @@ UNPACK_BUFFER EQU $6000 ; $6000 - $9800, 14k, $3800
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; $6000 - $C000 = 24k
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NUM_FILES EQU 15
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NUM_FILES EQU 2
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jmp chiptune_setup
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@ -126,32 +126,6 @@ mockingboard_found:
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; 4fe7 / 1e6 = .020s, 50Hz
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;============================
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; Draw title screen
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;============================
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; jsr set_gr_page0 ; set page 0
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; lda #$4 ; draw page 1
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; sta DRAW_PAGE
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; jsr clear_screens ; clear both screens
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; lda #<chip_title ; point to title data
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; sta GBASL
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; lda #>chip_title
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; sta GBASH
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; bit PAGE1
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; Load image ; load the image
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; lda #<$800
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; sta BASL
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; lda #>$800
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; sta BASH
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; jsr load_rle_gr
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;==================
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; load first song
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;==================
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@ -213,14 +187,6 @@ check_decompress:
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lda #0
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sta DECOMPRESS_TIME
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;============================
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; visualization
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;============================
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; jsr clear_top
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; jsr draw_rasters
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; jsr volume_bars
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; jsr page_flip
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check_done:
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lda #$ff
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bit DONE_PLAYING
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@ -397,10 +363,6 @@ done_name_loop:
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sta $777
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sta $B77
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; Point LZ4 src at proper place
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ldy #0
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@ -417,9 +379,9 @@ done_name_loop:
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adc #0
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sta LZ4_SRC+1
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lda #<UNPACK_BUFFER ; set input pointer
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lda #<UNPACK_BUFFER1 ; set input pointer
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sta INL
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lda #>UNPACK_BUFFER
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lda #>UNPACK_BUFFER1
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sta INH
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; Decompress first chunks
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@ -433,6 +395,14 @@ done_name_loop:
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sta DECODER_STATE
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sta COPY_TIME
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lda LZ4_SRC
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sta LZ4_SRC1
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sta LZ4_SRC2
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lda LZ4_SRC+1
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sta LZ4_SRC1+1
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sta LZ4_SRC2+1
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jsr setup_next_subsong
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rts
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@ -442,8 +412,16 @@ done_name_loop:
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;=================
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setup_next_subsong:
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;==============
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; Left side
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ldy #0
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lda LZ4_SRC1
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sta LZ4_SRC
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lda LZ4_SRC1+1
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sta LZ4_SRC+1
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lda (LZ4_SRC),Y ; get next size value
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sta LZ4_END
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iny
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@ -458,8 +436,57 @@ setup_next_subsong:
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adc #0
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sta LZ4_SRC+1
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lda #>UNPACK_BUFFER1 ; original unpacked data offset
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sta LZ4_DST+1
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lda #<UNPACK_BUFFER1
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sta LZ4_DST
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jsr lz4_decode ; decode
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lda LZ4_SRC
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sta LZ4_SRC1
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lda LZ4_SRC+1
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sta LZ4_SRC1+1
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;==================
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; right side
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ldy #0
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lda LZ4_SRC2
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sta LZ4_SRC
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lda LZ4_SRC2+1
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sta LZ4_SRC+1
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lda (LZ4_SRC),Y ; get next size value
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sta LZ4_END
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iny
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lda (LZ4_SRC),Y
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sta LZ4_END+1
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lda #2 ; increment pointer
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clc
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adc LZ4_SRC
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sta LZ4_SRC
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lda LZ4_SRC+1
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adc #0
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sta LZ4_SRC+1
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lda #>UNPACK_BUFFER1 ; original unpacked data offset
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sta LZ4_DST+1
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lda #<UNPACK_BUFFER1
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sta LZ4_DST
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jsr lz4_decode ; decode
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lda LZ4_SRC
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sta LZ4_SRC2
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lda LZ4_SRC+1
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sta LZ4_SRC2+1
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; tail-call?
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rts
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@ -513,13 +540,13 @@ bloop22:
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; DST: chunk_buffer+$2A00+(COPY_OFFSET*256)
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page_copy:
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clc ; 2
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lda #>(UNPACK_BUFFER+512) ; 3
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lda #>(UNPACK_BUFFER1+512) ; 3
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adc COPY_OFFSET ; 3
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adc COPY_OFFSET ; 3
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adc COPY_OFFSET ; 3
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sta page_copy_loop+2 ; self modify ; 5
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lda #>(UNPACK_BUFFER+$2A00) ; 2
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lda #>(UNPACK_BUFFER1+$2A00) ; 2
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adc COPY_OFFSET ; 3
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sta page_copy_loop+5 ; self modify ; 5
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@ -613,14 +640,14 @@ krw_file:
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;=========
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.include "../asm_routines/gr_offsets.s"
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.include "text_print.s"
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.include "../asm_routines/mockingboard_a.s"
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.include "mockingboard_a.s"
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.include "../asm_routines/gr_fast_clear.s"
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.include "../asm_routines/pageflip.s"
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;.include "../asm_routines/gr_unrle.s"
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.include "../asm_routines/gr_setpage.s"
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.include "qkumba_rts.s"
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.include "../asm_routines/gr_hlin.s"
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.include "../asm_routines/lz4_decode.s"
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.include "lz4_decode.s"
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.include "../asm_routines/keypress_minimal.s"
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.include "rasterbars.s"
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.include "volume_bars.s"
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@ -1,5 +1,5 @@
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5 PRINT
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5 GR
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10 PRINT "LOADING VMW CHIPTUNE PLAYER"
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20 PRINT "DYA SPECIAL EDITION V1.0"
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50 PRINT
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50 PRINT: X=PEEK(49237)
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100 PRINT CHR$ (4)"BRUN CHIPTUNE_PLAYER"
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@ -225,12 +225,12 @@ back_to_first_reg_b:
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back_to_first_reg_a:
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clc ; 2
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adc #>UNPACK_BUFFER ; in proper chunk 1 or 2 ; 2
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adc #>UNPACK_BUFFER1 ; in proper chunk 1 or 2 ; 2
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jmp update_r0_pointer ; 3
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back_to_first_reg_c:
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lda #>(UNPACK_BUFFER+$2A00) ; in linear C area ; 2
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lda #>(UNPACK_BUFFER1+$2A00) ; in linear C area ; 2
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update_r0_pointer:
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sta INH ; update r0 pointer ; 3
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207
dya/lz4_decode.s
Normal file
207
dya/lz4_decode.s
Normal file
@ -0,0 +1,207 @@
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; LZ4 data decompressor for Apple II
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; Code by Peter Ferrie (qkumba) (peter.ferrie@gmail.com)
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; "LZ4 unpacker in 143 bytes (6502 version) (2013)"
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; http://pferrie.host22.com/misc/appleii.htm
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; This is that code, but with comments and labels added for clarity.
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; I also found a bug when decoding with runs of multiples of 256
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; which has since been fixed upstream.
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; For LZ4 reference see
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; https://github.com/lz4/lz4/wiki/lz4_Frame_format.md
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; LZ4 summary:
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;
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; HEADER:
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; Should: check for magic number 04 22 4d 18
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; FLG: 64 in our case (01=version, block.index=1, block.checksum=0
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; size=0, checksum=1, reserved
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; MAX Blocksize: 40 (64kB)
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; HEADER CHECKSUM: a7
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; BLOCK HEADER: 4 bytes (le) If highest bit set, uncompressed!
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; BLOCKS:
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; Token byte. High 4-bits literal length, low 4-bits copy length
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; + If literal length==15, then following byte gets added to length
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; If that byte was 255, then keep adding bytes until not 255
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; + The literal bytes follow. There may be zero of them
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; + Next is block copy info. little-endian 2-byte offset to
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; be subtracted from current read position indicating source
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; + The low 4-bits of the token are the copy length, which needs
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; 4 added to it. As with the literal length, if it is 15 then
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; you read a byte and add (and if that byte is 255, keep adding)
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;LZ4_SRC EQU $00
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;LZ4_DST EQU $02
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;LZ4_END EQU $04
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;COUNT EQU $06
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;DELTA EQU $08
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;UNPACK_BUFFER EQU $5E00 ; offset of first unpacked byte
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;======================
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; LZ4 decode
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;======================
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; input buffer in LZ4_SRC
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; output buffer hardcoded still
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; size in ENDH:ENDL
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lz4_decode:
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lda LZ4_SRC ; packed data offset
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clc
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adc LZ4_END
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sta LZ4_END
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lda LZ4_SRC+1
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adc LZ4_END+1
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sta LZ4_END+1
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; lda #>UNPACK_BUFFER ; original unpacked data offset
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; sta LZ4_DST+1
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; lda #<UNPACK_BUFFER
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; sta LZ4_DST
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unpmain:
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ldy #0 ; used to index, always zero
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parsetoken:
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jsr getsrc ; get next token
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pha ; save for later (need bottom 4 bits)
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lsr ; number of literals in top 4 bits
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lsr ; so shift into place
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lsr
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lsr
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beq copymatches ; if zero, then no literals
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; jump ahead and copy
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jsr buildcount ; add up all the literal sizes
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; result is in ram[count+1]-1:A
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tax ; now in ram[count+1]-1:X
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jsr docopy ; copy the literals
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lda LZ4_SRC ; 16-bit compare
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cmp LZ4_END ; to see if we have reached the end
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lda LZ4_SRC+1
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sbc LZ4_END+1
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bcs done
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copymatches:
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jsr getsrc ; get 16-bit delta value
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sta DELTA
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jsr getsrc
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sta DELTA+1
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pla ; restore token
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and #$0f ; get bottom 4 bits
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; match count. 0 means 4
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; 15 means 19+, must be calculated
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jsr buildcount ; add up count bits, in ram[count+1]-:A
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clc
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adc #4 ; adjust count by 4 (minmatch)
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tax ; now in ramp[count+1]-1:X
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beq copy_no_adjust ; BUGFIX, don't increment if
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; exactly a multiple of 0x100
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bcc copy_no_adjust
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inc COUNT+1 ; increment if we overflowed
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copy_no_adjust:
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lda LZ4_SRC+1 ; save src on stack
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pha
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lda LZ4_SRC
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pha
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sec ; subtract delta
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lda LZ4_DST ; from destination, make new src
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sbc DELTA
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sta LZ4_SRC
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lda LZ4_DST+1
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sbc DELTA+1
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sta LZ4_SRC+1
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jsr docopy ; do the copy
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pla ; restore the src
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sta LZ4_SRC
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pla
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sta LZ4_SRC+1
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jmp parsetoken ; back to parsing tokens
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done:
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pla
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rts
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;=========
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; getsrc
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;=========
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; gets byte from src into A, increments pointer
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getsrc:
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lda (LZ4_SRC), Y ; get a byte from src
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inc LZ4_SRC ; increment pointer
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bne done_getsrc ; update 16-bit pointer
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inc LZ4_SRC+1 ; on 8-bit overflow
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done_getsrc:
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rts
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;============
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; buildcount
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;============
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buildcount:
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ldx #1 ; high count starts at 1
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stx COUNT+1 ; (loops at zero?)
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cmp #$0f ; if LITERAL_COUNT < 15, we are done
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bne done_buildcount
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buildcount_loop:
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sta COUNT ; save LITERAL_COUNT (15)
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jsr getsrc ; get the next byte
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tax ; put in X
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clc
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adc COUNT ; add new byte to old value
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bcc bc_8bit_oflow ; if overflow, increment high byte
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inc COUNT+1
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bc_8bit_oflow:
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inx ; check if read value was 255
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beq buildcount_loop ; if it was, keep looping and adding
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done_buildcount:
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rts
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;============
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; getput
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;============
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; gets a byte, then puts the byte
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getput:
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jsr getsrc
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; fallthrough to putdst
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;=============
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; putdst
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;=============
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; store A into destination
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putdst:
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sta (LZ4_DST), Y ; store A into destination
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inc LZ4_DST ; increment 16-bit pointer
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bne putdst_end ; if overflow, increment top byte
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inc LZ4_DST+1
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putdst_end:
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rts
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;=============================
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; docopy
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;=============================
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; copies ram[count+1]-1:X bytes
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; from src to dst
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docopy:
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docopy_loop:
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jsr getput ; get/put byte
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dex ; decrement count
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bne docopy_loop ; if not zero, loop
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dec COUNT+1 ; if zero, decrement high byte
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bne docopy_loop ; if not zero, loop
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rts
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206
dya/mockingboard_a.s
Normal file
206
dya/mockingboard_a.s
Normal file
@ -0,0 +1,206 @@
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; Mockingboad programming:
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; + Has two 6522 I/O chips connected to two AY-3-8910 chips
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; + Optionally has some speech chips controlled via the outport on the AY
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; + Often in slot 4
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; TODO: how to auto-detect?
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; References used:
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; http://macgui.com/usenet/?group=2&id=8366
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; 6522 Data Sheet
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; AY-3-8910 Data Sheet
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;========================
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; Mockingboard card
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; Essentially two 6522s hooked to the Apple II bus
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; Connected to AY-3-8910 chips
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; PA0-PA7 on 6522 connected to DA0-DA7 on AY
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; PB0 on 6522 connected to BC1
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; PB1 on 6522 connected to BDIR
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; PB2 on 6522 connected to RESET
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; left speaker
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MOCK_6522_ORB1 EQU $C400 ; 6522 #1 port b data
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MOCK_6522_ORA1 EQU $C401 ; 6522 #1 port a data
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MOCK_6522_DDRB1 EQU $C402 ; 6522 #1 data direction port B
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MOCK_6522_DDRA1 EQU $C403 ; 6522 #1 data direction port A
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; right speaker
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MOCK_6522_ORB2 EQU $C480 ; 6522 #2 port b data
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MOCK_6522_ORA2 EQU $C481 ; 6522 #2 port a data
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MOCK_6522_DDRB2 EQU $C482 ; 6522 #2 data direction port B
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MOCK_6522_DDRA2 EQU $C483 ; 6522 #2 data direction port A
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||||
; AY-3-8910 commands on port B
|
||||
; RESET BDIR BC1
|
||||
MOCK_AY_RESET EQU $0 ; 0 0 0
|
||||
MOCK_AY_INACTIVE EQU $4 ; 1 0 0
|
||||
MOCK_AY_READ EQU $5 ; 1 0 1
|
||||
MOCK_AY_WRITE EQU $6 ; 1 1 0
|
||||
MOCK_AY_LATCH_ADDR EQU $7 ; 1 1 1
|
||||
|
||||
|
||||
;========================
|
||||
; Mockingboard Init
|
||||
;========================
|
||||
; Initialize the 6522s
|
||||
; set the data direction for all pins of PortA/PortB to be output
|
||||
|
||||
mockingboard_init:
|
||||
lda #$ff ; all output (1)
|
||||
sta MOCK_6522_DDRB1
|
||||
sta MOCK_6522_DDRA1
|
||||
sta MOCK_6522_DDRB2
|
||||
sta MOCK_6522_DDRA2
|
||||
rts
|
||||
|
||||
;======================
|
||||
; Reset Left AY-3-8910
|
||||
;======================
|
||||
reset_ay_both:
|
||||
lda #MOCK_AY_RESET
|
||||
sta MOCK_6522_ORB1
|
||||
lda #MOCK_AY_INACTIVE
|
||||
sta MOCK_6522_ORB1
|
||||
|
||||
;======================
|
||||
; Reset Right AY-3-8910
|
||||
;======================
|
||||
;reset_ay_right:
|
||||
lda #MOCK_AY_RESET
|
||||
sta MOCK_6522_ORB2
|
||||
lda #MOCK_AY_INACTIVE
|
||||
sta MOCK_6522_ORB2
|
||||
rts
|
||||
|
||||
|
||||
; Write sequence
|
||||
; Inactive -> Latch Address -> Inactive -> Write Data -> Inactive
|
||||
|
||||
;=========================================
|
||||
; Write Right/Left to save value AY-3-8910
|
||||
;=========================================
|
||||
; register in X
|
||||
; value in MB_VALUE
|
||||
|
||||
write_ay_both:
|
||||
; address
|
||||
stx MOCK_6522_ORA1 ; put address on PA1 ; 3
|
||||
stx MOCK_6522_ORA2 ; put address on PA2 ; 3
|
||||
lda #MOCK_AY_LATCH_ADDR ; latch_address on PB1 ; 2
|
||||
sta MOCK_6522_ORB1 ; latch_address on PB1 ; 3
|
||||
sta MOCK_6522_ORB2 ; latch_address on PB2 ; 3
|
||||
lda #MOCK_AY_INACTIVE ; go inactive ; 2
|
||||
sta MOCK_6522_ORB1 ; 3
|
||||
sta MOCK_6522_ORB2 ; 3
|
||||
|
||||
; value
|
||||
lda MB_VALUE ; 3
|
||||
sta MOCK_6522_ORA1 ; put value on PA1 ; 3
|
||||
sta MOCK_6522_ORA2 ; put value on PA2 ; 3
|
||||
lda #MOCK_AY_WRITE ; ; 2
|
||||
sta MOCK_6522_ORB1 ; write on PB1 ; 3
|
||||
sta MOCK_6522_ORB2 ; write on PB2 ; 3
|
||||
lda #MOCK_AY_INACTIVE ; go inactive ; 2
|
||||
sta MOCK_6522_ORB1 ; 3
|
||||
sta MOCK_6522_ORB2 ; 3
|
||||
|
||||
rts ; 6
|
||||
;===========
|
||||
; 53
|
||||
;=======================================
|
||||
; clear ay -- clear all 14 AY registers
|
||||
; should silence the card
|
||||
;=======================================
|
||||
clear_ay_both:
|
||||
ldx #14
|
||||
lda #0
|
||||
sta MB_VALUE
|
||||
clear_ay_left_loop:
|
||||
jsr write_ay_both
|
||||
dex
|
||||
bpl clear_ay_left_loop
|
||||
rts
|
||||
|
||||
;=======================================
|
||||
; Detect a Mockingboard card
|
||||
;=======================================
|
||||
; Based on code from the French Touch "Pure Noise" Demo
|
||||
; Attempts to time an instruction sequence with a 6522
|
||||
;
|
||||
; If found, puts in bMB
|
||||
; MB_ADDRL:MB_ADDRH has address of Mockingboard
|
||||
; returns X=0 if not found, X=1 if found
|
||||
|
||||
mockingboard_detect:
|
||||
lda #0
|
||||
sta MB_ADDRL
|
||||
|
||||
mb_detect_loop: ; self-modifying
|
||||
lda #$07 ; we start in slot 7 ($C7) and go down to 0 ($C0)
|
||||
ora #$C0 ; make it start with C
|
||||
sta MB_ADDRH
|
||||
ldy #04 ; $CX04
|
||||
ldx #02 ; 2 tries?
|
||||
mb_check_cycle_loop:
|
||||
lda (MB_ADDRL),Y ; timer 6522 (Low Order Counter)
|
||||
; count down
|
||||
sta TEMP ; 3 cycles
|
||||
lda (MB_ADDRL),Y ; + 5 cycles = 8 cycles
|
||||
; between the two accesses to the timer
|
||||
sec
|
||||
sbc TEMP ; subtract to see if we had 8 cycles
|
||||
cmp #$f8 ; -8
|
||||
bne mb_not_in_this_slot
|
||||
dex ; decrement, try one more time
|
||||
bne mb_check_cycle_loop ; loop detection
|
||||
inx ; Mockingboard found (X=1)
|
||||
done_mb_detect:
|
||||
;stx bMB ; store result to bMB
|
||||
rts ; return
|
||||
|
||||
mb_not_in_this_slot:
|
||||
dec mb_detect_loop+1 ; decrement the "slot" (self_modify)
|
||||
bne mb_detect_loop ; loop down to one
|
||||
ldx #00
|
||||
beq done_mb_detect
|
||||
|
||||
|
||||
;=======================================
|
||||
; Detect a Mockingboard card in Slot4
|
||||
;=======================================
|
||||
; Based on code from the French Touch "Pure Noise" Demo
|
||||
; Attempts to time an instruction sequence with a 6522
|
||||
;
|
||||
; MB_ADDRL:MB_ADDRH has address of Mockingboard
|
||||
; returns X=0 if not found, X=1 if found
|
||||
|
||||
mockingboard_detect_slot4:
|
||||
lda #0
|
||||
sta MB_ADDRL
|
||||
|
||||
mb4_detect_loop: ; self-modifying
|
||||
lda #$04 ; we're only looking in Slot 4
|
||||
ora #$C0 ; make it start with C
|
||||
sta MB_ADDRH
|
||||
ldy #04 ; $CX04
|
||||
ldx #02 ; 2 tries?
|
||||
mb4_check_cycle_loop:
|
||||
lda (MB_ADDRL),Y ; timer 6522 (Low Order Counter)
|
||||
; count down
|
||||
sta TEMP ; 3 cycles
|
||||
lda (MB_ADDRL),Y ; + 5 cycles = 8 cycles
|
||||
; between the two accesses to the timer
|
||||
sec
|
||||
sbc TEMP ; subtract to see if we had 8 cycles
|
||||
cmp #$f8 ; -8
|
||||
bne mb4_not_in_this_slot
|
||||
dex ; decrement, try one more time
|
||||
bne mb4_check_cycle_loop ; loop detection
|
||||
inx ; Mockingboard found (X=1)
|
||||
done_mb4_detect:
|
||||
rts ; return
|
||||
|
||||
mb4_not_in_this_slot:
|
||||
ldx #00
|
||||
beq done_mb4_detect
|
||||
|
||||
@ -1,2 +1,3 @@
|
||||
.asciiz "DOTD1.KRW"
|
||||
.asciiz "DOTD2.KRW"
|
||||
|
||||
|
||||
@ -5,6 +5,8 @@ LZ4_DST EQU $02
|
||||
LZ4_END EQU $04
|
||||
COUNT EQU $06
|
||||
DELTA EQU $08
|
||||
LZ4_SRC1 EQU $0A
|
||||
LZ4_SRC2 EQU $0C
|
||||
|
||||
;; Zero page monitor routines addresses
|
||||
|
||||
|
||||
Loading…
Reference in New Issue
Block a user