psgport0 equ 0a0h ; Register select psgport1 equ 0a1h ; Data write psgport2 equ 0a2h ; Data read vdpport1 equ 099h ; VDP registers read/write i8255portb equ 0a9h ; keyboard column input i8255portc equ 0aah ; leds, motor, cassette, kbd line ; wrpsg: send value in A to PSG register ; syntax: wrpsg reg#,value ; modifies: A ; wrpsg macro reg,value ld a,reg out (psgport0),a ld a,value out (psgport1),a endm ; checkkbd: check keyboard line ; syntax: checkkbd ; modifies: AF ; checkkbd macro kbdline in a,(i8255portc) and 011110000b ; preserve high nibble or kbdline out (i8255portc),a in a,(i8255portb) endm ; jump to entry point ; jp start exit: xor a out (psgport0),a out (psgport1),a inc a out (psgport0),a xor a out (psgport1),a ld a,2 out (psgport0),a xor a out (psgport1),a ld a,3 out (psgport0),a xor a out (psgport1),a ld a,4 out (psgport0),a xor a out (psgport1),a ld a,5 out (psgport0),a xor a out (psgport1),a jr restoresys freezesys: ld hl,(00039h) ld (OLDINT),hl ld hl,newint ld (00039h),hl ret restoresys: ld hl,(OLDINT) ld (00039h),hl ld hl,(OLDSTACK) ld sp,hl ret newint: in a,(vdpport1) ld hl,(MUSPTR) ; channel a xor a out (psgport0),a ld a,(hl) out (psgport1),a ld a,1 out (psgport0),a inc hl ld a,(hl) out (psgport1),a inc hl ld a,2 ; channel b out (psgport0),a ld a,(hl) out (psgport1),a ld a,3 out (psgport0),a inc hl ld a,(hl) out (psgport1),a inc hl ld a,4 ; channel c out (psgport0),a ld a,(hl) out (psgport1),a ld a,5 out (psgport0),a inc hl ld a,(hl) out (psgport1),a inc hl ld bc,endmusic ; loop the song? ld a,b xor h jr nz,savemus ld a,c xor l jr nz,savemus ld hl,music savemus: ld (MUSPTR),hl checkkbd 7 and 000000100b ; ESC pressed? jp z,exit ; yes => return to MSX-DOS ei ret start: di ld (OLDSTACK),sp call freezesys ld hl,music ld (MUSPTR),hl wrpsg 8,15 ; Vol. channel 1 wrpsg 9,1 ; Vol. channel 2 wrpsg 10,15 ; Vol. channel 3 ei loop: halt jr loop ; ******** ; * Data * ; ******** ; OLDINT: defs 2 OLDSTACK: defs 2 MUSPTR: defs 2 TIMERA: defb 0 TIMERB: defb 0 TIMERC: defb 0 music: ; defb 0f1h,007h, 0fch,001h, 07fh,000h defb 0f1h,007h, 0fch,001h, 054h,000h defb 0f1h,007h, 0fch,001h, 06ah,000h defb 0f1h,007h, 0fch,001h, 07fh,000h defb 0f1h,007h, 0fch,001h, 065h,000h defb 0f1h,007h, 054h,000h, 06ah,000h defb 0f1h,007h, 054h,000h, 07fh,000h defb 0f1h,007h, 054h,000h, 054h,000h defb 0f1h,007h, 054h,000h, 06ah,000h defb 0f1h,007h, 054h,000h, 07fh,000h defb 0f8h,003h, 0fch,001h, 054h,000h defb 0f8h,003h, 0ffh,001h, 06ah,000h defb 0f8h,003h, 0fch,001h, 07fh,000h defb 0f8h,003h, 0fch,001h, 054h,000h defb 0f8h,003h, 0fch,001h, 06ah,000h defb 0f8h,003h, 07fh,000h, 07fh,000h defb 0f8h,003h, 07fh,000h, 054h,000h defb 0f8h,003h, 07fh,000h, 06ah,000h defb 0f8h,003h, 07fh,000h, 07fh,000h defb 0f8h,003h, 07fh,000h, 054h,000h defb 0f1h,007h, 0fch,001h, 06ah,000h defb 0f1h,007h, 0fch,001h, 07fh,000h defb 0f1h,007h, 0fch,001h, 054h,000h defb 0f1h,007h, 0fch,001h, 06ah,000h defb 0f1h,007h, 0fch,001h, 07fh,000h defb 0f1h,007h, 07fh,000h, 054h,000h defb 0f1h,007h, 07fh,000h, 06ah,000h defb 0f1h,007h, 07fh,000h, 07fh,000h defb 0f1h,007h, 07fh,000h, 054h,000h defb 0f1h,007h, 07fh,000h, 06ah,000h defb 0f8h,003h, 0fch,001h, 07fh,000h defb 0f8h,003h, 0fch,001h, 054h,000h defb 0f8h,003h, 0fch,001h, 06ah,000h defb 0f8h,003h, 0fch,001h, 07fh,000h defb 0f8h,003h, 0fch,001h, 054h,000h defb 0f8h,003h, 06ah,000h, 06ah,000h defb 0f8h,003h, 06ah,000h, 07fh,000h defb 0f8h,003h, 06ah,000h, 054h,000h defb 0f8h,003h, 06ah,000h, 06ah,000h defb 0f8h,003h, 06ah,000h, 07fh,000h defb 0f1h,007h, 0fch,001h, 054h,000h defb 0f1h,007h, 0fch,001h, 06ah,000h defb 0f1h,007h, 0fch,001h, 07fh,000h defb 0f1h,007h, 0fch,001h, 054h,000h defb 0f1h,007h, 0fch,001h, 06ah,000h defb 0f1h,007h, 07fh,000h, 07fh,000h defb 0f1h,007h, 07fh,000h, 054h,000h defb 0f1h,007h, 07fh,000h, 06ah,000h defb 0f1h,007h, 07fh,000h, 07fh,000h defb 0f1h,007h, 07fh,000h, 054h,000h defb 0f8h,003h, 0fch,001h, 06ah,000h defb 0f8h,003h, 0fch,001h, 07fh,000h defb 0f8h,003h, 0fch,001h, 054h,000h defb 0f8h,003h, 0fch,001h, 06ah,000h defb 0f8h,003h, 0fch,001h, 07fh,000h defb 0f8h,003h, 07fh,000h, 054h,000h defb 0f8h,003h, 07fh,000h, 06ah,000h defb 0f8h,003h, 07fh,000h, 07fh,000h defb 0f8h,003h, 07fh,000h, 054h,000h defb 0f8h,003h, 07fh,000h, 06ah,000h defb 0f1h,007h, 0fch,001h, 07fh,000h defb 0f1h,007h, 0fch,001h, 054h,000h defb 0f1h,007h, 0fch,001h, 06ah,000h defb 0f1h,007h, 0fch,001h, 07fh,000h defb 0f1h,007h, 0fch,001h, 054h,000h defb 0f1h,007h, 054h,000h, 06ah,000h defb 0f1h,007h, 054h,000h, 07fh,000h defb 0f1h,007h, 054h,000h, 054h,000h defb 0f1h,007h, 054h,000h, 06ah,000h defb 0f1h,007h, 054h,000h, 07fh,000h defb 0f8h,003h, 0fch,001h, 054h,000h defb 0f8h,003h, 0fch,001h, 06ah,000h defb 0f8h,003h, 0fch,001h, 07fh,000h defb 0f8h,003h, 0fch,001h, 054h,000h defb 0f8h,003h, 0fch,001h, 06ah,000h defb 0f8h,003h, 07fh,000h, 07fh,000h defb 0f8h,003h, 07fh,000h, 054h,000h defb 0f8h,003h, 07fh,000h, 06ah,000h defb 0f8h,003h, 07fh,000h, 07fh,000h defb 0f8h,003h, 07fh,000h, 054h,000h ; defb 001h,005h, 0fch,001h, 0a0h,000h defb 001h,005h, 0fch,001h, 06ah,000h defb 001h,005h, 0fch,001h, 086h,000h defb 001h,005h, 0fch,001h, 0a0h,000h defb 001h,005h, 0fch,001h, 06ah,000h defb 001h,005h, 05ch,000h, 086h,000h defb 001h,005h, 05ch,000h, 0a0h,000h defb 001h,005h, 05ch,000h, 06ah,000h defb 001h,005h, 05ch,000h, 086h,000h defb 001h,005h, 05ch,000h, 0a0h,000h defb 080h,002h, 0fch,001h, 0a0h,000h defb 080h,002h, 0fch,001h, 06ah,000h defb 080h,002h, 0fch,001h, 086h,000h defb 080h,002h, 0fch,001h, 0a0h,000h defb 080h,002h, 0fch,001h, 06ah,000h defb 080h,002h, 07fh,000h, 086h,000h defb 080h,002h, 07fh,000h, 0a0h,000h defb 080h,002h, 07fh,000h, 06ah,000h defb 080h,002h, 07fh,000h, 086h,000h defb 080h,002h, 07fh,000h, 0a0h,000h defb 001h,005h, 0fch,001h, 0a0h,000h defb 001h,005h, 0fch,001h, 06ah,000h defb 001h,005h, 0fch,001h, 086h,000h defb 001h,005h, 0fch,001h, 0a0h,000h defb 001h,005h, 0fch,001h, 06ah,000h defb 001h,005h, 07fh,000h, 086h,000h defb 001h,005h, 07fh,000h, 0a0h,000h defb 001h,005h, 07fh,000h, 06ah,000h defb 001h,005h, 07fh,000h, 086h,000h defb 001h,005h, 07fh,000h, 0a0h,000h defb 080h,002h, 0fch,001h, 0a0h,000h defb 080h,002h, 0fch,001h, 06ah,000h defb 080h,002h, 0fch,001h, 086h,000h defb 080h,002h, 0fch,001h, 0a0h,000h defb 080h,002h, 0fch,001h, 06ah,000h defb 080h,002h, 06ah,000h, 086h,000h defb 080h,002h, 06ah,000h, 0a0h,000h defb 080h,002h, 06ah,000h, 06ah,000h defb 080h,002h, 06ah,000h, 086h,000h defb 080h,002h, 06ah,000h, 0a0h,000h defb 001h,005h, 0fch,001h, 0a0h,000h defb 001h,005h, 0fch,001h, 06ah,000h defb 001h,005h, 0fch,001h, 086h,000h defb 001h,005h, 0fch,001h, 0a0h,000h defb 001h,005h, 0fch,001h, 06ah,000h defb 001h,005h, 07fh,000h, 086h,000h defb 001h,005h, 07fh,000h, 0a0h,000h defb 001h,005h, 07fh,000h, 06ah,000h defb 001h,005h, 07fh,000h, 086h,000h defb 001h,005h, 07fh,000h, 0a0h,000h defb 080h,002h, 0fch,001h, 0a0h,000h defb 080h,002h, 0fch,001h, 06ah,000h defb 080h,002h, 0fch,001h, 086h,000h defb 080h,002h, 0fch,001h, 0a0h,000h defb 080h,002h, 0fch,001h, 06ah,000h defb 080h,002h, 07fh,000h, 086h,000h defb 080h,002h, 07fh,000h, 0a0h,000h defb 080h,002h, 07fh,000h, 06ah,000h defb 080h,002h, 07fh,000h, 086h,000h defb 080h,002h, 07fh,000h, 0a0h,000h defb 001h,005h, 0fch,001h, 0a0h,000h defb 001h,005h, 0fch,001h, 06ah,000h defb 001h,005h, 0fch,001h, 086h,000h defb 001h,005h, 0fch,001h, 0a0h,000h defb 001h,005h, 0fch,001h, 06ah,000h defb 001h,005h, 054h,000h, 086h,000h defb 001h,005h, 054h,000h, 0a0h,000h defb 001h,005h, 054h,000h, 06ah,000h defb 001h,005h, 054h,000h, 086h,000h defb 001h,005h, 054h,000h, 086h,000h defb 080h,002h, 0fch,001h, 0a0h,000h defb 080h,002h, 0fch,001h, 06ah,000h defb 080h,002h, 0fch,001h, 086h,000h defb 080h,002h, 0fch,001h, 0a0h,000h defb 080h,002h, 0fch,001h, 06ah,000h defb 080h,002h, 07fh,000h, 086h,000h defb 080h,002h, 07fh,000h, 0a0h,000h defb 080h,002h, 07fh,000h, 06ah,000h defb 080h,002h, 07fh,000h, 086h,000h defb 080h,002h, 07fh,000h, 0a0h,000h ; defb 0eah,008h, 0fch,001h, 08eh,000h defb 0eah,008h, 0fch,001h, 05fh,000h defb 0eah,008h, 0fch,001h, 077h,000h defb 0eah,008h, 0fch,001h, 08eh,000h defb 0eah,008h, 0fch,001h, 05fh,000h defb 0eah,008h, 000h,000h, 077h,000h defb 0eah,008h, 000h,000h, 08eh,000h defb 0eah,008h, 000h,000h, 05fh,000h defb 0eah,008h, 000h,000h, 077h,000h defb 0eah,008h, 000h,000h, 08eh,000h defb 075h,004h, 0fch,001h, 08eh,000h defb 075h,004h, 0fch,001h, 05fh,000h defb 075h,004h, 0fch,001h, 077h,000h defb 075h,004h, 0fch,001h, 08eh,000h defb 075h,004h, 0fch,001h, 05fh,000h defb 075h,004h, 000h,000h, 077h,000h defb 075h,004h, 000h,000h, 08eh,000h defb 075h,004h, 000h,000h, 05fh,000h defb 075h,004h, 000h,000h, 077h,000h defb 075h,004h, 000h,000h, 08eh,000h defb 0eah,008h, 0fch,001h, 08eh,000h defb 0eah,008h, 0fch,001h, 05fh,000h defb 0eah,008h, 0fch,001h, 077h,000h defb 0eah,008h, 0fch,001h, 08eh,000h defb 0eah,008h, 0fch,001h, 05fh,000h defb 0eah,008h, 000h,000h, 077h,000h defb 0eah,008h, 000h,000h, 08eh,000h defb 0eah,008h, 000h,000h, 05fh,000h defb 0eah,008h, 000h,000h, 077h,000h defb 0eah,008h, 000h,000h, 08eh,000h defb 075h,004h, 0fch,001h, 08eh,000h defb 075h,004h, 0fch,001h, 05fh,000h defb 075h,004h, 0fch,001h, 077h,000h defb 075h,004h, 0fch,001h, 08eh,000h defb 075h,004h, 0fch,001h, 05fh,000h defb 075h,004h, 000h,000h, 077h,000h defb 075h,004h, 000h,000h, 08eh,000h defb 075h,004h, 000h,000h, 05fh,000h defb 075h,004h, 000h,000h, 077h,000h defb 075h,004h, 000h,000h, 08eh,000h defb 0eah,008h, 0fch,001h, 08eh,000h defb 0eah,008h, 0fch,001h, 05fh,000h defb 0eah,008h, 0fch,001h, 077h,000h defb 0eah,008h, 0fch,001h, 08eh,000h defb 0eah,008h, 0fch,001h, 05fh,000h defb 0eah,008h, 000h,000h, 077h,000h defb 0eah,008h, 000h,000h, 08eh,000h defb 0eah,008h, 000h,000h, 05fh,000h defb 0eah,008h, 000h,000h, 077h,000h defb 0eah,008h, 000h,000h, 08eh,000h defb 075h,004h, 0fch,001h, 08eh,000h defb 075h,004h, 0fch,001h, 05fh,000h defb 075h,004h, 0fch,001h, 077h,000h defb 075h,004h, 0fch,001h, 08eh,000h defb 075h,004h, 0fch,001h, 05fh,000h defb 075h,004h, 000h,000h, 077h,000h defb 075h,004h, 000h,000h, 08eh,000h defb 075h,004h, 000h,000h, 05fh,000h defb 075h,004h, 000h,000h, 077h,000h defb 075h,004h, 000h,000h, 08eh,000h defb 0eah,008h, 0fch,001h, 08eh,000h defb 0eah,008h, 0fch,001h, 05fh,000h defb 0eah,008h, 0fch,001h, 077h,000h defb 0eah,008h, 0fch,001h, 08eh,000h defb 0eah,008h, 0fch,001h, 05fh,000h defb 0eah,008h, 000h,000h, 077h,000h defb 0eah,008h, 000h,000h, 08eh,000h defb 0eah,008h, 000h,000h, 05fh,000h defb 0eah,008h, 000h,000h, 077h,000h defb 0eah,008h, 000h,000h, 08eh,000h defb 075h,004h, 0fch,001h, 08eh,000h defb 075h,004h, 0fch,001h, 05fh,000h defb 075h,004h, 0fch,001h, 077h,000h defb 075h,004h, 0fch,001h, 08eh,000h defb 075h,004h, 0fch,001h, 05fh,000h defb 075h,004h, 000h,000h, 077h,000h defb 075h,004h, 000h,000h, 08eh,000h defb 075h,004h, 000h,000h, 05fh,000h defb 075h,004h, 000h,000h, 077h,000h defb 075h,004h, 000h,000h, 08eh,000h ; defb 09ah,00ah, 0fch,001h, 0a9h,000h defb 09ah,00ah, 0fch,001h, 071h,000h defb 09ah,00ah, 0fch,001h, 08eh,000h defb 09ah,00ah, 0fch,001h, 0a9h,000h defb 09ah,00ah, 0fch,001h, 071h,000h defb 09ah,00ah, 000h,000h, 08eh,000h defb 09ah,00ah, 000h,000h, 0a9h,000h defb 09ah,00ah, 000h,000h, 071h,000h defb 09ah,00ah, 000h,000h, 08eh,000h defb 09ah,00ah, 000h,000h, 0a9h,000h defb 04dh,005h, 0fch,001h, 0a9h,000h defb 04dh,005h, 0fch,001h, 071h,000h defb 04dh,005h, 0fch,001h, 08eh,000h defb 04dh,005h, 0fch,001h, 0a9h,000h defb 04dh,005h, 0fch,001h, 071h,000h defb 04dh,005h, 000h,000h, 08eh,000h defb 04dh,005h, 000h,000h, 0a9h,000h defb 04dh,005h, 000h,000h, 071h,000h defb 04dh,005h, 000h,000h, 08eh,000h defb 04dh,005h, 000h,000h, 0a9h,000h defb 09ah,00ah, 0fch,001h, 0a9h,000h defb 09ah,00ah, 0fch,001h, 071h,000h defb 09ah,00ah, 0fch,001h, 08eh,000h defb 09ah,00ah, 0fch,001h, 0a9h,000h defb 09ah,00ah, 0fch,001h, 071h,000h defb 09ah,00ah, 000h,000h, 08eh,000h defb 09ah,00ah, 000h,000h, 0a9h,000h defb 09ah,00ah, 000h,000h, 071h,000h defb 09ah,00ah, 000h,000h, 08eh,000h defb 09ah,00ah, 000h,000h, 0a9h,000h defb 04dh,005h, 0fch,001h, 0a9h,000h defb 04dh,005h, 0fch,001h, 071h,000h defb 04dh,005h, 0fch,001h, 08eh,000h defb 04dh,005h, 0fch,001h, 0a9h,000h defb 04dh,005h, 0fch,001h, 071h,000h defb 04dh,005h, 000h,000h, 08eh,000h defb 04dh,005h, 000h,000h, 0a9h,000h defb 04dh,005h, 000h,000h, 071h,000h defb 04dh,005h, 000h,000h, 08eh,000h defb 04dh,005h, 000h,000h, 0a9h,000h defb 0eah,008h, 0fch,001h, 08eh,000h defb 0eah,008h, 0fch,001h, 05fh,000h defb 0eah,008h, 0fch,001h, 077h,000h defb 0eah,008h, 0fch,001h, 08eh,000h defb 0eah,008h, 0fch,001h, 05fh,000h defb 0eah,008h, 000h,000h, 077h,000h defb 0eah,008h, 000h,000h, 08eh,000h defb 0eah,008h, 000h,000h, 05fh,000h defb 0eah,008h, 000h,000h, 077h,000h defb 0eah,008h, 000h,000h, 08eh,000h defb 075h,004h, 0fch,001h, 08eh,000h defb 075h,004h, 0fch,001h, 05fh,000h defb 075h,004h, 0fch,001h, 077h,000h defb 075h,004h, 0fch,001h, 08eh,000h defb 075h,004h, 0fch,001h, 05fh,000h defb 075h,004h, 000h,000h, 077h,000h defb 075h,004h, 000h,000h, 08eh,000h defb 075h,004h, 000h,000h, 05fh,000h defb 075h,004h, 000h,000h, 077h,000h defb 075h,004h, 000h,000h, 08eh,000h defb 0eah,008h, 0fch,001h, 08eh,000h defb 0eah,008h, 0fch,001h, 05fh,000h defb 0eah,008h, 0fch,001h, 077h,000h defb 0eah,008h, 0fch,001h, 08eh,000h defb 0eah,008h, 0fch,001h, 05fh,000h defb 0eah,008h, 000h,000h, 077h,000h defb 0eah,008h, 000h,000h, 08eh,000h defb 0eah,008h, 000h,000h, 05fh,000h defb 0eah,008h, 000h,000h, 077h,000h defb 0eah,008h, 000h,000h, 08eh,000h defb 075h,004h, 0fch,001h, 08eh,000h defb 075h,004h, 0fch,001h, 05fh,000h defb 075h,004h, 0fch,001h, 077h,000h defb 075h,004h, 0fch,001h, 08eh,000h defb 075h,004h, 0fch,001h, 05fh,000h defb 075h,004h, 000h,000h, 077h,000h defb 075h,004h, 000h,000h, 08eh,000h defb 075h,004h, 000h,000h, 05fh,000h defb 075h,004h, 000h,000h, 077h,000h defb 075h,004h, 000h,000h, 08eh,000h endmusic: defb 000h  000h,000h, 05fh,000h defb 075h,004h, 000h,000h, 08eh,000h defb 075h,004h, 000h,000h, 05fh,000h defb 075h,004h, 000h,000h, 08eh,000h defb 075h,004h, 000h,000h, 05fh,000h endmusic: defb 000h