CHAPTER 11 BUZZER OUTPUT CONTROLLER
188
User’s Manual U11302EJ4V0UM
Figure 11-2. Format of Timer Clock Select Register 2
Cautions 1. Be sure to stop operation of the watch timer or buzzer to be changed before rewriting
TCL2 (stopping operation is not necessary when rewriting the same data).
The operation is stopped by the following methods.
• Buzzer output: Input 0 to bit 7 (TCL27) of TCL2
• Watch timer:
Input 0 to bit 2 (TMC22) of the watch timer mode control register
(TMC2)
2. Changing the count clock (rewriting TCL20 to TCL22) after watchdog timer operation
has started is prohibited.
Remarks 1.
f
X
: Main system clock oscillation frequency
2.
f
XT
: Subsystem clock oscillation frequency
3.
x:
don’t care
4.
Figures in parentheses apply to operation with f
X
= 5.0 MHz or f
XT
= 32.768 kHz.
TCL20
TCL2
7
6
5
4
3
2
Symbol
1
0
TCL22
Count clock selection
FF42H
TCL21
0
TCL22
TCL24
TCL25
TCL26
TCL27
Address
After reset
R/W
00H
R/W
Watchdog timer mode
0
f
X
/2
3
(625 kHz)
0
f
X
/2
4
(313 kHz)
0
f
X
/2
5
(156 kHz)
0
f
X
/2
6
(78.1 kHz)
1
f
X
/2
7
(39.1 kHz)
1
f
X
/2
8
(19.5 kHz)
1
f
X
/2
9
(9.8 kHz)
1
f
X
/2
11
(2.4 kHz)
TCL24 Watch timer count clock selection
0
f
X
/2
8
(19.5 kHz)
1
f
XT
(32.768 kHz)
TCL27
Buzzer output frequency selection
0
Buzzer output disabled
1
f
X
/2
10
(4.9 kHz)
1
f
X
/2
11
(2.4 kHz)
1
f
X
/2
12
(1.2 kHz)
1
Setting prohibited
Interval timer mode
f
X
/2
4
(313 kHz)
f
X
/2
5
(156 kHz)
f
X
/2
6
(78.1 kHz)
f
X
/2
7
(39.1 kHz)
f
X
/2
8
(19.5 kHz)
f
X
/2
9
(9.8 kHz)
f
X
/2
10
(4.9 kHz)
f
X
/2
12
(1.2 kHz)
TCL21
0
0
1
1
0
0
1
1
TCL20
0
1
0
1
0
1
0
1
TCL26
x
0
0
1
1
TCL25
x
0
1
0
1