Subversion Repositories rtf65002

; ============================================================================
;        __
;   \\__/ o\    (C) 2013, 2014  Robert Finch, Stratford
;    \  __ /    All rights reserved.
;     \/_//     robfinch<remove>@opencores.org
;       ||
;  
;
; This source file is free software: you can redistribute it and/or modify 
; it under the terms of the GNU Lesser General Public License as published 
; by the Free Software Foundation, either version 3 of the License, or     
; (at your option) any later version.                                      
;                                                                          
; This source file is distributed in the hope that it will be useful,      
; but WITHOUT ANY WARRANTY; without even the implied warranty of           
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the            
; GNU General Public License for more details.                             
;                                                                          
; You should have received a copy of the GNU General Public License        
; along with this program.  If not, see <http://www.gnu.org/licenses/>.    
;
; Piano.asm                                                                         
; ============================================================================
;
;--------------------------------------------------------------------------
;--------------------------------------------------------------------------
; 
public Piano:
        jsr             RequestIOFocus
        lda             #15                             ; master volume to max
        sta             PSG+64
playnt:
        jsr             KeybdGetChar
        cmp             #CTRLC
        beq             PianoX
        cmp             #'a'
        beq             playnt1a
        cmp             #'b'
        beq             playnt1b
        cmp             #'c'
        beq             playnt1c
        cmp             #'d'
        beq             playnt1d
        cmp             #'e'
        beq             playnt1e
        cmp             #'f'
        beq             playnt1f
        cmp             #'g'
        beq             playnt1g
        bra             playnt
PianoX:
        jsr             ReleaseIOFocus
        rts

playnt1a:
        ld              r4,#7217
        bra             playnta
playnt1b:
        ld              r4,#8101
        bra             playnta
playnt1c:
        ld              r4,#4291
        bra             playnta
playnt1d:
        ld              r4,#4817
        bra             playnta
playnt1e:
        ld              r4,#5407
        bra             playnta
playnt1f:
        ld              r4,#5728
        bra             playnta
playnt1g:
        ld              r4,#6430
playnta
        lda             #1      ; priority 1
        ldx             #0      ; no flags
        ldy             #Tone
        ld              r5,#5                   ; associate with JCB #5
        int             #4
        db              1                               ; start task
        bra             playnt

; The PSG supports four voices, so we use all the voices in succession.
; The Tone task is reentrant. Multiple copies of the tone task may be
; playing tones at the same time.
;
Tone:
        pha
        phx
        inc             tone_cnt
        ldx             tone_cnt
        and             r2,r2,#3
        asl             r2,r2,#2                ; PSG has groups of four registers
        sta             PSGFREQ0,x
        ; decay  (16.384 ms)2
        ; attack (8.192 ms)1
        ; release (1.024 s)A
        ; sustain level C
        lda             #0xCA12
        sta             PSGADSR0,x
        lda             #0x1104                 ; gate, output enable, triangle waveform
        sta             PSGCTRL0,x
        lda             #20                             ; delay about 100ms
        int             #4
        db              5                               ; Sleep
;       jsr             Delay10
        lda             #0x0104                 ; gate off, output enable, triangle waveform
        sta             PSGCTRL0,x
        lda             #20                             ; delay about 100ms
        int             #4
        db              5                               ; Sleep
;       jsr             Delay10
        lda             #0x0000                 ; gate off, output enable off, no waveform
        sta             PSGCTRL0,x
        plx
        pla
        rts

; This routine used when Sleep() didn't work.
Delay10:
        lda             #500000
dly10a:
        dea
        bne             dly10a
        rts