66 lines
1.9 KiB
C
66 lines
1.9 KiB
C
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/***************************************************************************
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* __________ __ ___.
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* Open \______ \ ____ ____ | | _\_ |__ _______ ___
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* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
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* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
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* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
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* \/ \/ \/ \/ \/
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* $Id$
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*
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* Copyright (C) 2002 by Bj<EFBFBD>rn Stenberg
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
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* KIND, either express or implied.
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*
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****************************************************************************/
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#include "config.h"
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#include "system.h"
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#include "kernel.h"
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#include "panic.h"
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void tick_start(unsigned int interval_in_ms)
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{
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unsigned long count;
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count = CPU_FREQ * interval_in_ms / 1000 / 8;
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if(count > 0x10000)
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{
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panicf("Error! The tick interval is too long (%d ms)\n",
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interval_in_ms);
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return;
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}
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/* We are using timer 0 */
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TSTR &= ~0x01; /* Stop the timer */
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TSNC &= ~0x01; /* No synchronization */
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TMDR &= ~0x01; /* Operate normally */
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TCNT0 = 0; /* Start counting at 0 */
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GRA0 = (unsigned short)(count - 1);
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TCR0 = 0x23; /* Clear at GRA match, sysclock/8 */
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/* Enable interrupt on level 1 */
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IPRC = (IPRC & ~0x00f0) | 0x0010;
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TSR0 &= ~0x01;
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TIER0 = 0xf9; /* Enable GRA match interrupt */
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TSTR |= 0x01; /* Start timer 1 */
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}
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void IMIA0(void) __attribute__ ((interrupt_handler));
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void IMIA0(void)
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{
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/* Run through the list of tick tasks */
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call_tick_tasks();
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TSR0 &= ~0x01;
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}
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