64 lines
1.8 KiB
C
64 lines
1.8 KiB
C
/***************************************************************************
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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 Linus Nielsen Feltzing
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*
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* All files in this archive are subject to the GNU General Public License.
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* See the file COPYING in the source tree root for full license agreement.
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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 "sh7034.h"
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#include "system.h"
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#include "debug.h"
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#include "kernel.h"
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void tick_start(unsigned int interval_in_ms)
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{
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unsigned int count;
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count = FREQ / 1000 / 8 * interval_in_ms;
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debugf("count = %d\n", count);
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if(count > 0xffff)
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{
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debugf("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 = count;
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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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#pragma interrupt
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void IMIA0(void)
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{
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current_tick++;
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// debugf("t\n");
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TSR0 &= ~0x01;
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}
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