Renesas Stereo System SH7709S Manual Do Utilizador
Rev. 5.00, 09/03, page 397 of 760
12.2.4
Timer Constant Registers (TCOR)
The TMU has three TCOR registers, one for each channel. TCOR specifies the value for setting in
TCNT when a TCNT count-down results in an under flow.
TCNT when a TCNT count-down results in an under flow.
TCOR is a 32-bit readable/writable register. TCOR is initialized to H'FFFFFFFF by a power-on
reset or manual reset, but is not initialized, and retains its contents, in standby mode.
reset or manual reset, but is not initialized, and retains its contents, in standby mode.
Bit:
31
30
29
28
27
26
25
24
Initial value:
1
1
1
1
1
1
1
1
R/W:
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Bit:
23
22
21
20
19
18
17
16
Initial value:
1
1
1
1
1
1
1
1
R/W:
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Bit:
15
14
13
12
11
10
9
8
Initial value:
1
1
1
1
1
1
1
1
R/W:
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Bit:
7
6
5
4
3
2
1
0
Initial value:
1
1
1
1
1
1
1
1
R/W:
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
12.2.5
Timer Counters (TCNT)
The timer counters are 32-bit readable/writable registers. The TMU has three timer counters, one
for each channel.
for each channel.
TCNT counts down upon input of a clock. The clock input is selected using the TPSC2
–
TPSC0
bits in the timer control register (TCR).
When a TCNT count-down results in an underflow (H'00000000
→
H'FFFFFFFF), the underflow
flag (UNF) in the timer control register (TCR) of the relevant channel is set. The TCOR value is
simultaneously set in TCNT itself and the count-down continues from that value.
simultaneously set in TCNT itself and the count-down continues from that value.