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VMEchip2
Tick Timer 1 Compare Register
2
ADR/SIZ
BIT
NAME
OPER
RESET
Tick Timer 1 Counter
ADR/SIZ
BIT
NAME
OPER
RESET
2-70
31
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 (µs)
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 zero, the time to the first
interrupt may be longer or shorter than expected. Remember the
rollover time for the counter is 71.6 minutes.
31
This is the tick timer 1 counter. When enabled, it increments every
microsecond. Software may read or write the counter at any time.
$FFF40050 (32 bits)
. . .
R/W
0 P
$FFF40054 (32 bits)
. . .
Tick timer 1 Counter
R/W
0 P
0
0
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