From cb7b8f5c43e447e50d701c32ba52b2338586001e Mon Sep 17 00:00:00 2001 From: Vince Weaver Date: Sat, 17 Feb 2018 16:01:25 -0500 Subject: [PATCH] asm: add dos33 routines taken from my ll program --- asm_routines/dos33_routines.s | 230 ++++++++++++++++++++++++++++++++++ chiptune_player/TODO | 7 ++ 2 files changed, 237 insertions(+) create mode 100644 asm_routines/dos33_routines.s create mode 100644 chiptune_player/TODO diff --git a/asm_routines/dos33_routines.s b/asm_routines/dos33_routines.s new file mode 100644 index 00000000..701d455b --- /dev/null +++ b/asm_routines/dos33_routines.s @@ -0,0 +1,230 @@ +; File I/O routines based on sample code in +; "Beneath Apple DOS" by Don Worth and Pieter Lechner + +;; For the disk-read code +RWTSH EQU $F1 +RWTSL EQU $F0 +DOSBUFH EQU $EF +DOSBUFL EQU $EE +FILEMH EQU $ED +FILEML EQU $EC + +;; DOS Constants +OPEN EQU $01 +CLOSE EQU $02 +READ EQU $03 +WRITE EQU $04 +DELETE EQU $05 +CATALOG EQU $06 +LOCK EQU $07 +UNLOCK EQU $08 +RENAME EQU $09 +POSITION EQU $0A +INIT EQU $0B +VERIFY EQU $0C + +LOCATE_FILEM_PARAM EQU $3DC +LOCATE_RWTS_PARAM EQU $3E3 +FILEMANAGER EQU $3D6 + + + ;================================ + ; read from disk + ;================================ + + jsr LOCATE_FILEM_PARAM ; load file manager param list + ; Y=low A=high + + sta FILEMH + sty FILEML + + ldy #7 ; file type offset = 7 + lda #0 ; 0 = text + sta (FILEML),y + + iny ; filename ptr offset = 8 + lda #filename + sta (FILEML),y + + ldx #1 ; open existing file + + jsr open ; open file + + jsr read ; read buffer + + jsr close ; close file + + +;================================= +; get_dos_buffer +;================================= +; +; Dos buffer format +; 0x000-0x0ff = data buffer +; 0x100-0x1ff = t/s list buffer +; 0x200-0x22c = file manager workarea (45 bytes) +; 0x22d-0x24a = file name buffer + +; 0x24b-0x24c = address of file manager workarea +; 0x24d-0x24e = address of t/s list buffer +; 0x24f-0x250 = adress of data sector buffer +; 0x251-0x252 = address of file name field for the next buffer + +; In DOS, $3D2 points to 0x22d of first buffer +; add 0x24 to get chain pointer + + +open: + ; allocate one of the DOS buffers so we don't have to set them up + +allocate_dos_buffer: + lda $3D2 ; DOS load point + sta DOSBUFH + ldy #0 + sty DOSBUFL + +buf_loop: + lda (DOSBUFL),Y ; locate next buffer + pha ; push on stack + ; we need this later + ; to test validity + + iny ; increment y + lda (DOSBUFL),Y ; load next byte + sta DOSBUFH ; store to buffer pointerl + + pla ; restore value from stack + + sta DOSBUFL ; store to buffer pointerh + + bne found_buffer ; if not zero, found a buffer + + lda DOSBUFH ; also if not zero, found a buffer + beq error ; no buffer found, exit + +found_buffer: + ldy #0 ; get filename + lda (DOSBUFL),Y ; get first byte + beq good_buffer ; if zero, good buffer + + ; in use + ldy #$24 ; point to next + bne buf_loop ; and loop + +good_buffer: + lda #$78 + sta (DOSBUFL),Y ; mark as in use (can be any !0) + +keep_opening: + ldy #0 + lda #OPEN ; set operation code to OPEN + sta (FILEML),y + + ldy #2 ; point to record length + lda #0 ; set it to zero (16-bits) + sta (FILEML),y + iny + sta (FILEML),y + + iny ; point to volume num (0=any) + sta (FILEML),y + + jsr LOCATE_RWTS_PARAM ; get current RWTS parameters + ; so we can get disk/slot info + + sty RWTSL + sta RWTSH + + ldy #1 + lda (RWTSL),y ; get slot*16 + lsr a + lsr a + lsr a + lsr a ; divide by 16 + + ldy #6 ; address of slot + sta (FILEML),y ; store it + + ldy #2 + lda (RWTSL),y ; get drive + ldy #5 ; address of drive + sta (FILEML),y + +filemanager_interface: + + ldy #$1E +dbuf_loop: + lda (DOSBUFL),y ; get three buffer pointers + pha ; push onto stack + iny ; increment pointer + cpy #$24 ; have we incremented 6 times? + bcc dbuf_loop ; if not, loop + + ldy #$11 ; point to the end of the same struct + ; in file manager +fmgr_loop: + pla ; pop value + sta (FILEML),Y ; store it + dey ; work backwards + cpy #$c ; see if we are done + bcs fmgr_loop ; loop + + jmp FILEMANAGER ; run filemanager + + +;==================== +; close DOS file +;==================== + +close: + ldy #0 ; command offset + lda #CLOSE ; load close + sta (FILEML),y + + jsr filemanager_interface + + ldy #0 ; mark dos buffer as free again + tya + sta (DOSBUFL),y + + rts + +;========================= +; read from dos file +;========================= + +read: + ldy #0 ; command offset + lda #READ + sta (FILEML),y + + iny ; point to sub-opcode + lda #2 ; "range of bytes" + sta (FILEML),y + + ldy #6 ; point to number of bytes to read + lda #$ff + sta (FILEML),y ; we want to read 255 bytes + iny + lda #$00 + sta (FILEML),y + + ldy #8 ; buffer address + lda #disk_buff + sta (FILEML),y + + bne filemanager_interface ; same as JMP + +filename: +; CPUINFO__6502 (padded to be 30 chars long) +.byte $C3,$D0,$D5,$C9,$CE,$C6,$CF,$DF +.byte $DF,$B6,$B5,$B0,$B2,$A0,$A0,$A0 +.byte $A0,$A0,$A0,$A0,$A0,$A0,$A0,$A0 +.byte $A0,$A0,$A0,$A0,$A0,$A0 + diff --git a/chiptune_player/TODO b/chiptune_player/TODO new file mode 100644 index 00000000..749e2854 --- /dev/null +++ b/chiptune_player/TODO @@ -0,0 +1,7 @@ ++ Load from disk ++ Starfield ++ Volume Bars ++ Print Descriptive Text ++ Print time ++ LZ4 decompression ++ Loop support