diff options
Diffstat (limited to 'c/src/lib/libbsp/m68k/gen68302/timer/timerisr.s')
| -rw-r--r-- | c/src/lib/libbsp/m68k/gen68302/timer/timerisr.s | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/c/src/lib/libbsp/m68k/gen68302/timer/timerisr.s b/c/src/lib/libbsp/m68k/gen68302/timer/timerisr.s new file mode 100644 index 0000000000..c804b9dfa6 --- /dev/null +++ b/c/src/lib/libbsp/m68k/gen68302/timer/timerisr.s @@ -0,0 +1,28 @@ +/* + * Handle 68302 TIMER2 interrupts. + * + * All code in this routine is pure overhead which can perturb the + * accuracy of RTEMS' timing test suite. + * + * See also: Read_timer() + * + * 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. + * + * An external counter, Timer_interrupts, is incremented. + * + * $Id$ + */ + +#include "asm.h" + +BEGIN_CODE + PUBLIC(timerisr) +SYM(timerisr): + move.w #0x0040,SYM(m302)+2072 | clear interrupt in-service bit + move.b #3,SYM(m302)+2137 | clear timer interrupt event register + addq.l #1,SYM(Timer_interrupts) | increment timer value + rte +END_CODE +END |