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# timer_isr()
#
# This routine provides the ISR for the Z8036 timer on the MVME136
# board. The timer is set up to generate an interrupt at maximum
# intervals.
#
# Input parameters: NONE
#
# Output parameters: NONE
#
# COPYRIGHT (c) 1989, 1990, 1991, 1992, 1993, 1994.
# On-Line Applications Research Corporation (OAR).
# All rights assigned to U.S. Government, 1994.
#
# This material may be reproduced by or for the U.S. Government pursuant
# to the copyright license under the clause at DFARS 252.227-7013. This
# notice must appear in all copies of this file and its derivatives.
#
# $Id$
#
#include "asm.h"
BEGIN_CODE
.set CT1_CMD_STATUS, 0xfffb000a | port A
.set RELOAD, 0x24 | clr IP & IUS,allow countdown
PUBLIC (timerisr)
SYM (timerisr):
movl a0,a7@- | save a0
movl #CT1_CMD_STATUS,a0 | a0 = addr of cmd status reg
movb #RELOAD,a0@ | reload countdown
addql #1, SYM (Ttimer_val) | increment timer value
movl a7@+,a0 | save a0
rte
END_CODE
END
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