EC-PM-80320 Service Manual
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Relative signal is shown as Figure 3-3.
3.2.3 USB Interface
USB interface is 2.0 Full-Speed version.
Contact Number Signal Name Typical Wiring Assignment
1 VBUS Red
2 D- White
3 D+ Green
4 GND Black
3.2.4 Serial Interface
EC-PM-80320 printer’s serial interface is compatible with RS-232C protocol, supporting RTS/CTS
and XON/XOFF handshaking protocol. Its connector is a DB-9 type connector and each pin’s
definitions are shown as figure 3-5.
Table 3-3 Pin assignments of the serial interface
Pin Number Signal From Description
2 RXD Host Receive data from Host
3 TXD Printer Sent control code X-ON/X-OFF and data to the Host
8 CTS Printer
“MARK” state means printer is too busy to receive
data; “SPACE” means printer is ready for receiving
data.
5 GND — Signal GND
BUSY
/ACK
DATA
/STB
0.5μS
0.5μS
0.5μS
0.5μS
0.5μS
Figure 3-4 USB interface
Figure 3-3 Timing signal in parallel interface
Figure 3-5 Sequence numbers of Serial connector
2 1
3 4
5 1
9 6