13. Buzzer driver
A96G140/A96G148/A96A148 User’s manual
150
13
Buzzer driver
A buzzer of A96G140/A96G148/A96A148 consists of 8-bit counter, a buzzer data register (BUZDR),
and a buzzer control register (BUZCR). It outputs square wave (61.035Hz to 125.0KHz @ 8MHz)
through P13/AN10/EC1/BUZO pin, and its buzzer data register (BUZDR) controls the buzzer frequency
(refer to the following expression). In a buzzer control register (BUZCR), BUCK[1:0] bits select a source
clock divided by prescaler.
Table 26. Buzzer Frequency at 8MHz
BUZDR[7:0]
Buzzer Frequency (KHz)
BUZCR[2:1]=00
BUZCR[2:1]=01
BUZCR[2:1]=10
BUZCR[2:1]=11
0000_0000
125KHz
62.5KHz
31.25KHz
15.625KHz
0000_0001
62.5KHz
31.25KHz
15.625KHz
7.812KHz
…
…
…
…
…
1111_1101
492.126Hz
246.063Hz
123.031Hz
61.515Hz
1111_1110
490.196Hz
245.098Hz
122.549Hz
61.274Hz
1111_1111
488.281Hz
244.141Hz
122.07Hz
61.035Hz
13.1
Buzzer driver block diagram
Pre
scaler
fx
MUX
Counter
fx/32
fx/64
fx/128
fx/256
2
BUCK[1:0]
8-bit Up-Counter
BUZDR
Comparator
F/F
Clear
BUZO
BUZEN
Figure 78. Buzzer Driver Block Diagram
13.2
Register map
1)
(BUZDR
Ratio
Prescaler
2
Frequency
Oscillator
(Hz)
f
BUZ
+
=