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/* timer_isr()
*
* This routine provides the ISR for the MC68230 timer on the Motorola
* IDP board. The timer is set up to generate an interrupt at maximum
* intervals.
*
* Code modified by Doug McBride, Colorado Space Grant College
* countdown should be loaded automatically
*
* Input parameters: NONE
*
* Output parameters: NONE
*
* COPYRIGHT (c) 1989-1999.
* On-Line Applications Research Corporation (OAR).
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.com/license/LICENSE.
*
* $Id$
*/
#include <rtems/asm.h>
BEGIN_CODE
.set TSR, 0x00c0106B | base address of PIT register "TSR"
PUBLIC (timerisr)
SYM (timerisr):
movb #1,TSR | acknowledge interrupt
addql #1, SYM (Ttimer_val) | increment timer value
rte
END_CODE
END
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