Motorola MVME2300 Series 用户手册
2-78
Computer Group Literature Center Web Site
Raven PCI Bridge ASIC
2
Timer Current Count Registers
T
Toggle. This bit toggles when ever the current count
decrements to zero.
decrements to zero.
CC
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.
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 Base Count Registers
Offset
Timer 0 - $01100
Timer 1 - $01140
Timer 2 - $01180
Timer 3 - $011C0
Bit
3
1
1
3
0
0
2
9
9
2
8
8
2
7
7
2
6
6
2
5
5
2
4
4
2
3
3
2
2
2
2
1
1
2
0
0
1
9
9
1
8
8
1
7
7
1
6
6
1
5
5
1
4
4
1
3
3
1
2
2
1
1
1
1
0 9 8 7 6 5 4 3 2 1 0
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
1
3
0
0
2
9
9
2
8
8
2
7
7
2
6
6
2
5
5
2
4
4
2
3
3
2
2
2
2
1
1
2
0
0
1
9
9
1
8
8
1
7
7
1
6
6
1
5
5
1
4
4
1
3
3
1
2
2
1
1
1
1
0 9 8 7 6 5 4 3 2 1 0
0 9 8 7 6 5 4 3 2 1 0
Name
TIMER BASECOUNT
CI
BC
Operation
R/
W
W
R/W
Reset
1
$00000000