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Computer Group Literature Center Web Site
Raven PCI Host Bridge & Multi-Processor Interrupt Controller
2
Timer Current Count Registers
T TOGGLE. This bit toggles when ever the current count decrements to
zero.
CC CURRENT COUNT. The current count field decrements while the
Count Inhibit bit is the Base Count Register is zero. When the timer counts
down to zero, the Current Count register is reloaded from the Base Count
register and the timer’s interrupt becomes pending in the MPIC
processing.
Timer Basecount Registers
Offset
Timer 0 - $01100
Timer 1 - $01140
Timer 2 - $01180
Timer 3 - $011C0
Bit
3
1
3
0
2
9
2
8
2
7
2
6
2
5
2
4
2
3
2
2
2
1
2
0
1
9
1
8
1
7
1
6
1
5
1
4
1
3
1
2
1
1
1
0 9 8 7 6 5 4 3 2 1 0
Name
TIMER CURRENT COUNT
T
CC
Operation
R
R
Reset
0
$00000000
Offset
Timer 0 - $01110
Timer 1 - $01150
Timer 2 - $01190
Timer 3 - $011D0
Bit
3
1
3
0
2
9
2
8
2
7
2
6
2
5
2
4
2
3
2
2
2
1
2
0
1
9
1
8
1
7
1
6
1
5
1
4
1
3
1
2
1
1
1
0 9 8 7 6 5 4 3 2 1 0
Name
TIMER BASECOUNT
CI
BC
Operation
R/W
R/W
Reset
1
$00000000