Buzzer Output Circuit; Fig. 2.42 Buzzer Output Circuit Block Diagram - Fujitsu MB89140 Series Hardware Manual

BUZZER OUTPUT
CIRCUIT
TBCR
10.0 MHz
1/2
frequency
Time-base timer

Fig. 2.42 Buzzer Output Circuit Block Diagram

HARDWARE CONFIGURATION

2.13 BUZZER OUTPUT CIRCUIT

The buzzer output sound for checking key input can be output.
Two frequencies can be output by setting the registers.
Block Diagram
Internal bus
BUZR
TBR BUZ1 BUZ0
CLR
Select
10
1/2 10
11
1/2 11
CK
Selector
Registers
The buzzer output block has buzzer register (BUZR).
Address: 000E
H
2-83
P-ch high-withstand-voltage port
8 bit
BUZR R/W Buzzer register
BZ