20
EPSON
E0C6006 TECHNICAL MANUAL
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Output Ports)
BZ, BZ (R03, R02)
The output ports R03 and R02 can be set to BZ output port and BZ output (BZ reverse output) port,
respectively. However, when FOUT output is selected for the R02 terminal, BZ output cannot be selected.
Direct driving of piezo-electric buzzer
By setting the R03 to the BZ output port and the R02 to the BZ output port, these two terminals can
directly drive a piezo-electric buzzer. The BZ output (R02) can only be set if the R03 is set to the BZ
output.
At initial reset, the output terminals go low.
When "1" is written to the BZ (R03)/BZ (R02) registers, the output terminals output the buzzer signals.
When "0" is written, the terminals go low.
Figure 4.5.3.3 shows the buzzer direct drive waveform.
R03/R02 register
BZ output waveform
BZ output waveform
0
1
0
Fig. 4.5.3.3 Buzzer output waveform (direct driving)
Single terminal driving of piezo-electric buzzer
The piezo-electric buzzer can be driven with one terminal by setting the R03 to the BZ output terminal.
At initial reset, the BZ output goes off and the output terminal (R03) is set to low level.
When "1" is written to the BZ (R03) register, the output terminal output the BZ signal.
Figure 4.5.3.4 shows the BZ output waveform in single terminal driving.
R03 register
BZ output waveform
0
1
0
Fig. 4.5.3.4 Buzzer output waveform (single terminal driving)
Busser signal frequency
The buzzer signal frequency can be selected from 2 types (f
OSC1
/8, f
OSC1
/16) by the mask option. When
the OSC1 oscillation frequency is 32.768 kHz, they becomes 4 kHz and 2 kHz, respectively.