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Computer Group Literature Center Web Site
VMEchip2
2
Tick Timer 1 Compare Register
The tick timer 1 counter is compared to this register. When they are equal,
an interrupt is sent to the local bus interrupter and the overflow counter is
incremented. If the clear-on-compare mode is enabled, the counter is also
cleared. For periodic interrupts, the following equation should be used to
calculate the compare register value for a specific period (T).
compare register value = T (
µ
s)
When programming the tick timer for periodic interrupts, the counter
should be cleared to zero by software and then enabled. If the counter does
not initially start at 0, the time to the first interrupt may be longer or shorter
than expected. Remember the rollover time for the counter is 71.6 minutes.
Tick Timer 1 Counter
This is the tick timer 1 counter. When enabled, it increments every
microsecond. Software may read or write the counter at any time.
ADR/SIZ
$FFF40050 (32 bits)
BIT
31
. . .
0
NAME
Tick timer 1 Compare Register
OPER
R/W
RESET
0 P
ADR/SIZ
$FFF40054 (32 bits)
BIT
31
. . .
0
NAME
Tick timer 1 Counter
OPER
R/W
RESET
0 P
Summary of Contents for MVME1X7P
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Page 90: ...1 64 Computer Group Literature Center Web Site Programming Issues 1 ...
Page 248: ...3 50 Computer Group Literature Center Web Site PCCchip2 3 ...
Page 286: ...4 38 Computer Group Literature Center Web Site MCECC Functions 4 ...
Page 288: ...A 2 Computer Group Literature Center Web Site Summary of Changes A ...
Page 316: ...Index IN 14 Computer Group Literature Center Web Site I N D E X ...