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Timer Current Count Registers
Offset
Bit
3
3
2
2
1
0
9
8
Name
Operation
Reset
T
CC
Timer Basecount Registers
Offset
Bit
3
3
2
2
1
0
9
8
Name
Operation
Reset
CI
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Timer 0 - $01100
Timer 1 - $01140
Timer 2 - $01180
Timer 3 - $011C0
2
2
2
2
2
2
2
2
1
7
6
5
4
3
2
1
0
9
TIMER CURRENT COUNT
TOGGLE. This bit toggles whenever the current count
decrements to zero.
CURRENT COUNT. The current count field decrements
while the Count Inhibit bit in the Base Count Register is
zero. When the timer counts down to zero, the Current
Count register is reloaded from the Base Count register.
Timer 0 - $01110
Timer 1 - $01150
Timer 2 - $01190
Timer 3 - $011D0
2
2
2
2
2
2
2
2
1
7
6
5
4
3
2
1
0
9
TIMER BASECOUNT
COUNT INHIBIT. Setting this bit to one inhibits
counting for this timer. Setting this bit to zero allows
counting to proceed.
Raven Interrupt Controller Implementation
1
1
1
1
1
1
1
1
1
8
7
6
5
4
3
2
1
0 9 8 7 6 5 4 3 2 1 0
CC
R
$00000000
1
1
1
1
1
1
1
1
1
8
7
6
5
4
3
2
1
0 9 8 7 6 5 4 3 2 1 0
BC
R/W
$00000000
2
2-77
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