almost works

diff --git a/Makefile b/Makefile
index 26a0553..4da4343 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -1,13 +1,17 @@
 bin = bootcard.img
+com = bootcard.com
 
-QEMU_FLAGS = -soundhw pcspk
+QEMU_FLAGS = -soundhw pcspk -device sb16
 
 $(bin): bootcard.asm
        nasm -f bin -o $@ $<
 
+$(com): bootcard.asm
+       nasm -f bin -o $@ $< -DDOS
+
 .PHONY: clean
 clean:
-       rm -f $(bin)
+       rm -f $(bin) $(com)
 
 .PHONY: run
 run: $(bin)
@@ -28,3 +32,10 @@ qr: bootcard.asm
 .PHONY: install
 install: $(bin)
        dd if=$(bin) of=/dev/sdd bs=512
+
+.PHONY: com
+com: $(com)
+
+.PHONY: rundos
+rundos: $(com)
+       dosbox-x $(com)

diff --git a/bootcard.asm b/bootcard.asm
index dddf846..1f29b88 100644 (file)
--- a/bootcard.asm
+++ b/bootcard.asm
@@ -2,19 +2,40 @@
 ; nasm -f bin -o bootcard.img bootcard.asm
 ; cat bootcard.img >/dev/<usbstick>
 
-       org 7c00h
+%define MIDI
+
        bits 16
+%ifdef DOS
+       org 100h
+       jmp start
+%else
+       org 7c00h
+%endif
 
 barh   equ 4
 nbars  equ 11
 barstart equ 200 - (nbars+1) * barh
 
+%ifdef DOS
+nticks         dd 0
+tmoffs         dd 0
+musptr         dd 0
+frame  dd 0
+pnote  dd 0
+fval   dd 0
+cmap   dd 0
+
+saved_tintr_offs dw 0
+saved_tintr_seg dw 0
+%else
 nticks equ 7e00h
 tmoffs equ 7e04h
 musptr equ 7e08h
 frame  equ 7e0ch
+pnote  equ 7e18h
 fval   equ 7e10h
 cmap   equ 7e14h
+%endif
 
 %macro setcur 2
        mov dx, %1 | (%2 << 8)
@@ -41,7 +62,9 @@ cmap  equ 7e14h
        out 40h + %1, al
 %endmacro
 
-start: xor ax, ax
+start:
+%ifndef DOS
+       xor ax, ax
        mov ds, ax
        mov es, ax
        mov ss, ax
@@ -54,9 +77,29 @@ start:       xor ax, ax
        cli
        mov word [32], tintr
        mov [34], ax
+%else
+       ; for DOS save the previous interrupt handler to restore at the end
+       xor ax, ax
+       mov es, ax
+       mov ax, [es:32]
+       mov [saved_tintr_offs], ax
+       mov ax, [es:34]
+       mov [saved_tintr_seg], ax
 
-       stimer 0, 5966
+       cli
+       mov ax, ds
+       mov word [es:32], tintr
+       mov [es:34], ax
+%endif
 
+       stimer 0, 5966
+%ifdef MIDI
+       call resetmidi
+       mov ax, 0c0h    ; change program on chan 0
+       call sendmidi
+       mov ax, 19      ; church organ
+       call sendmidi
+%endif
        mov ax, 13h
        int 10h
        push 0a000h
@@ -133,7 +176,27 @@ drawbg:
        mov cx, 16 * 3
        rep outsb
 
+%ifdef DOS
+       in al, 60h
+       dec al
+       jnz mainloop
+
+       mov ax, 3
+       int 10h
+
+       cli
+       xor ax, ax
+       mov es, ax
+       mov ax, [saved_tintr_offs]
+       mov word [es:32], ax
+       mov ax, [saved_tintr_seg]
+       mov [es:34], ax
+       stimer 0, 0xffff
+       sti
+       ret
+%else
        jmp mainloop
+%endif
 
 textout:
        mov al, [si]
@@ -146,6 +209,61 @@ textout:
        jmp textout
 .done: ret
 
+%ifdef MIDI
+note_on:
+       mov [pnote], ax
+       mov ax, 90h     ; note-on command for channel 0
+       call sendmidi
+       mov ax, [pnote]
+       call sendmidi
+       mov ax, 127
+       call sendmidi
+       ret
+
+note_off:
+       mov ax, 80h     ; note-off command for channel 0
+       call sendmidi
+       mov ax, [pnote]
+       call sendmidi
+       mov ax, 64
+       call sendmidi
+       ret
+
+all_notes_off:
+       mov ax, 0b0h    ; channel mode message for channel 0...
+       call sendmidi
+       mov ax, 7bh     ; all notes off
+       call sendmidi
+       xor ax, ax
+       call sendmidi
+       ret
+
+waitmidi:
+       mov ax, 331h
+.wait: in al, dx       ; read status port
+       test al, 40h    ; test output-ready bit (0: ready)
+       jnz .wait
+       ret
+
+sendmidi:
+       push dx
+       push ax
+       call waitmidi
+       pop ax
+       dec dx
+       out dx, al
+       pop dx
+       ret
+
+resetmidi:
+       call waitmidi
+       mov ax, 0ffh    ; reset command
+       out dx, al
+       call waitmidi
+       mov ax, 3fh     ; enter UART mode
+       out dx, al
+       ret
+%endif ; MIDI
 
 tintr:
        pusha
@@ -154,7 +272,11 @@ tintr:
        mov [nticks], ax
 
        mov bx, [musptr]
+%ifdef MIDI
+       cmp bx, 22*2
+%else
        cmp bx, 22*3
+%endif
        jnz .skiploop
        xor bx, bx
        mov [tmoffs], ax
@@ -166,25 +288,45 @@ tintr:
        cmp ax, cx
        jb .end
 
+%ifdef MIDI
+       call note_off
+       mov al, [music + 1 + bx]
+       xor ah, ah
+       add bx, 2
+%else
        mov ax, [music + 1 + bx]
        add bx, 3
+%endif
        mov [musptr], bx
        test ax, ax
        jz .off
 
        mov bx, ax
+%ifdef MIDI
+       sub bx, 43
+%else
        shr bx, 9
        sub bx, 13
+%endif
        imul bx, bx, 3
        mov byte [cmap + bx], 3fh
        mov word [cmap + bx + 1], 2f2fh
 
+%ifdef MIDI
+       call note_on
+%else
        mov bx, ax
        stimer 2, bx
        spkon
+%endif
        jmp .end
 
-.off:  spkoff
+.off:
+%ifdef MIDI
+       call all_notes_off
+%else
+       spkoff
+%endif
 
 .end:  test word [nticks], 1
        jnz .eoi
@@ -207,20 +349,71 @@ tintr:
 
 str1:  db 'Michael ',3,' Athena',0
 
-music: dd 0a2f8f00h, 0a11123a1h, 23a11423h, 28000023h, 0be322f8fh, 25c0391fh
-       dd 4b23a13ch, 8f500000h, 23a15a2fh, 641ab161h, 476e1ab1h, 1fbe751ch
-       dd 8223a178h, 0a18925c0h, 1fbe8c23h, 0aa0000a0h
-       dw 0
+%ifdef MIDI
+G2     equ 43
+C3     equ 48
+D3     equ 50
+B2     equ 47
+F3     equ 53
+E3     equ 52
+%else
+G2      equ 12175
+C3      equ 9121
+D3      equ 8126
+B2      equ 9664
+F3      equ 6833
+E3      equ 7239
+%endif
+
+
+%ifdef MIDI
+%macro EV 2
+       db %1 >> 4
+       db %2
+%endmacro
+%else
+%macro EV 2
+       db %1 >> 4
+       dw %2
+%endmacro
+%endif
+
+music: EV     0,  G2
+       EV   160,  C3
+       EV   272,  C3
+       EV   320,  C3
+       EV   560,  0
+       EV   640,  G2
+       EV   800,  D3
+       EV   912,  B2
+       EV   960,  C3
+       EV  1200,  0
+       EV  1280,  G2
+       EV  1440,  C3
+       EV  1552,  F3
+       EV  1600,  F3
+       EV  1760,  E3
+       EV  1872,  D3
+       EV  1920,  C3
+       EV  2080,  B2
+       EV  2192,  C3
+       EV  2240,  D3
+       EV  2560,  0
+       EV  2720,  0
 
 w5:    dw 5
 w30:   dw 30
 
+%ifndef DOS
+%ifndef MIDI
        times 446-($-$$) db 0
        dd 00212080h
        dd 0820280ch
        dd 00000800h
        dd 0001f800h
+%endif
 
        times 510-($-$$) db 0
        dw 0aa55h
+%endif
 ; vi:ft=nasm ts=8 sts=8 sw=8: