SDL_mintaudio_it.S
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/*
SDL - Simple DirectMedia Layer
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Copyright (C) 1997-2012 Sam Lantinga
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This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
Sam Lantinga
slouken@libsdl.org
*/
/*
Audio interrupts
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Patrice Mandin, Didier Méquignon
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*/
.text
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.globl _SDL_MintAudio_XbiosInterruptMeasureClock
.globl _SDL_MintAudio_clocktics
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.globl _SDL_MintAudio_XbiosInterrupt
.globl _SDL_MintAudio_Dma8Interrupt
.globl _SDL_MintAudio_StfaInterrupt
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.globl _SDL_MintAudio_num_its
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/*--- Xbios interrupt vector to measure Falcon external clock ---*/
_SDL_MintAudio_XbiosInterruptMeasureClock: /* 1 mS */
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/* state DMA sound */
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#if defined(__mcoldfire__)
movel d0,sp@-
moveql #0,d0
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btst d0,0xFFFF8901:w
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btst #0,0xFFFF8901:w
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beqs SDL_MintAudio_EndIntMeasure
addql #1,_SDL_MintAudio_clocktics
SDL_MintAudio_EndIntMeasure:
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/* Clear service bit */
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#if defined(__mcoldfire__)
moveql #5,d0
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bclr d0,0xFFFFFA0F:w
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movel sp@+,d0
#else
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bclr #5,0xFFFFFA0F:w
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/*--- Interrupt vectors ---*/
/* Xbios, DMA 8 bits: need to set ISR on MFP */
/* STFA: do not touch MFP */
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_SDL_MintAudio_XbiosInterrupt:
_SDL_MintAudio_Dma8Interrupt:
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#if defined(__mcoldfire__)
lea sp@(-12),sp
moveml d0-d1/a0,sp@
#else
moveml d0-d1/a0,sp@-
#endif
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/* Clear service bit, so other MFP interrupts can work */
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#if defined(__mcoldfire__)
moveql #5,d0
bclr d0,0xfffffa0f:w
#else
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bclr #5,0xfffffa0f:w
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_SDL_MintAudio_StfaInterrupt:
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move.l _SDL_MintAudio_num_its,d0
addql #1,d0
move.l d0,_SDL_MintAudio_num_its
cmp.l #5,d0
bmi.s _SDL_MintAudio_nosilence
move.l _SDL_MintAudio_itbuffer,d1
beq.s _SDL_MintAudio_nosilence
move.l d1,a0
move.l _SDL_MintAudio_itbuflen,d0
move.l _SDL_MintAudio_itsilence,d1
_SDL_MintAudio_fillsilence:
move.l d1,a0@+
subq.l #1,d0
bpl.s _SDL_MintAudio_fillsilence
_SDL_MintAudio_nosilence:
#if defined(__mcoldfire__)
moveml sp@,d0-d1/a0
lea sp@(12),sp
#else
moveml sp@+,d0-d1/a0
#endif
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.even
.comm _SDL_MintAudio_clocktics,4
.comm _SDL_MintAudio_num_its,4
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.comm _SDL_MintAudio_itbuffer,4 /* Audio DMA buffer */
.comm _SDL_MintAudio_itbuflen,4 /* Length in longword */
.comm _SDL_MintAudio_itsilence,4 /* Silence value */