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[/] [psg16/] [trunk/] [software/] [code snippets/] [Beep.asm] - Blame information for rev 2

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PSG                     EQU             0xFFFF_FFFF_FFD5_0000
PSGFREQ0        EQU             0xFFFF_FFFF_FFD5_0000
PSGPW0          EQU             0xFFFF_FFFF_FFD5_0002
PSGCTRL0        EQU             0xFFFF_FFFF_FFD5_0004
PSGADSR0        EQU             0xFFFF_FFFF_FFD5_0006
 
;--------------------------------------------------------------------------
; Sound a 800 Hz beep
;--------------------------------------------------------------------------
;
Beep:
        subui   sp,sp,#16
        sm              [sp],r1/lr
        ori             r1,r0,#15               ; master volume to max
        sc              r1,PSG+128
        ori             r1,r0,#13422    ; 800Hz
        sc              r1,PSGFREQ0
        ; decay  (16.384 ms)2
        ; attack (8.192 ms)1
        ; release (1.024 s)A
        ; sustain level C
        setlo   r1,#0xCA12
        sc              r1,PSGADSR0
        ori             r1,r0,#0x1104   ; gate, output enable, triangle waveform
        sc              r1,PSGCTRL0
        ori             r1,r0,#25000000 ; delay about 1s
beep1:
        loop    r1,beep1
        ori             r1,r0,#0x0104   ; gate off, output enable, triangle waveform
        sc              r1,PSGCTRL0
        ori             r1,r0,#25000000 ; delay about 1s
beep2:
        loop    r1,beep2
        ori             r1,r0,#0x0000   ; gate off, output enable off, no waveform
        sc              r1,PSGCTRL0
        lm              [sp],r1/lr
        ret             #16
 

Line No.	Rev	Author	Line
1	2	robfinch	`PSG EQU 0xFFFF_FFFF_FFD5_0000`
2			`PSGFREQ0 EQU 0xFFFF_FFFF_FFD5_0000`
3			`PSGPW0 EQU 0xFFFF_FFFF_FFD5_0002`
4			`PSGCTRL0 EQU 0xFFFF_FFFF_FFD5_0004`
5			`PSGADSR0 EQU 0xFFFF_FFFF_FFD5_0006`
6
7			`;--------------------------------------------------------------------------`
8			`; Sound a 800 Hz beep`
9			`;--------------------------------------------------------------------------`
10			`;`
11			`Beep:`
12			`subui sp,sp,#16`
13			`sm [sp],r1/lr`
14			`ori r1,r0,#15 ; master volume to max`
15			`sc r1,PSG+128`
16			`ori r1,r0,#13422 ; 800Hz`
17			`sc r1,PSGFREQ0`
18			`; decay (16.384 ms)2`
19			`; attack (8.192 ms)1`
20			`; release (1.024 s)A`
21			`; sustain level C`
22			`setlo r1,#0xCA12`
23			`sc r1,PSGADSR0`
24			`ori r1,r0,#0x1104 ; gate, output enable, triangle waveform`
25			`sc r1,PSGCTRL0`
26			`ori r1,r0,#25000000 ; delay about 1s`
27			`beep1:`
28			`loop r1,beep1`
29			`ori r1,r0,#0x0104 ; gate off, output enable, triangle waveform`
30			`sc r1,PSGCTRL0`
31			`ori r1,r0,#25000000 ; delay about 1s`
32			`beep2:`
33			`loop r1,beep2`
34			`ori r1,r0,#0x0000 ; gate off, output enable off, no waveform`
35			`sc r1,PSGCTRL0`
36			`lm [sp],r1/lr`
37			`ret #16`
38

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[/] [psg16/] [trunk/] [software/] [code snippets/] [Beep.asm] - Blame information for rev 2