Epson LQ-2550 Technical Manual page 151

2.3.10 Buzzer Drive Circuit
This printer uses a piezo-buzzer to confirm control panel switch input and indicate errors. Figure 2-98
shows the buzzer drive circuit and Figure 2-99 shows the its pulse timing.
R7
3.3K
10
R35
Figure 2-98. Buzzer Drive Circuit
5
0
5
0
Buzzer sounds when there is no paper.
Figure 2-99. Buzzer Drive Circuit Pulse Timing
11 8
SUB CPU
(7 B)
Buzzer on stote
2-105
REV.-A