Initial revision

1 files changed, 37 insertions, 0 deletions

diff --git a/c/src/lib/libbsp/no_cpu/no_bsp/timer/timerisr.c b/c/src/lib/libbsp/no_cpu/no_bsp/timer/timerisr.c
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index 0000000000..f52774b75e
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+++ b/c/src/lib/libbsp/no_cpu/no_bsp/timer/timerisr.c
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+/*  timerisr.s
+ *
+ *  If required this ISR is used to bump a count of interval "overflow"
+ *  interrupts which have occurred since the timer was started.  The
+ *  number of overflows is taken into account in the Read_timer()
+ *  routine if necessary.
+ *
+ *  To reduce overhead this is best to be the "rawest" hardware interupt
+ *  handler you can write.  This should be the only interrupt which can
+ *  occur during the measured time period.
+ *
+ *  NOTE:  This file is USUALLY in assembly and is LEAN AND MEAN.
+ *         Any code in this isr is pure overhead which can perturb
+ *         the accuracy of the Timing Test Suite.
+ *
+ *  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 <rtems.h>
+
+extern rtems_unsigned32 _Timer_interrupts;
+
+void timerisr( void )
+{
+  /*
+   *  _Timer_interrupts += TIMER_BETWEEN_OVERFLOWS  (usually in microseconds)
+   *  return from interrupt
+   */
+}