Tick Timer 1 Control Register - Motorola MVME1X7P Programmer's Reference Manual

Tick Timer 1 Control Register

This is an 8-bit read/write register that controls Tick Timer 1. It is located
at address $FFF42017.
ADR/SIZ
BIT
7
NAME
OVF3
OPER
R
RESET
0 PL
CEN
COC
COVF
OVF3-OVF0 These four bits are the outputs of the overflow counter.
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$FFF42017 (8 bits)
6 5 4
OVF2 OVF1 OVF0
R R R
0 PL 0 PL 0 PL
Counter Enable. When this bit is high, the counter
increments. When this bit is low, the counter does not
increment.
Clear On Compare. When this bit is high, the counter is
reset to zero when it compares with the compare register.
When this bit is low, the counter is not reset.
Clear Overflow Counter. The overflow counter is cleared
when a one is written to this bit.
The overflow counter is incremented each time the tick
timer sends an interrupt to the Local Bus interrupter. The
overflow counter can be cleared by writing a one to the
COVF control bit.
Programming Model
3 2 1
COVF COC
R C R/W
0 0 PL 0 PL
3
0
CEN
R/W
0 PL
3-23