Serial Interface With - Epson PP 803 User Manual

1.2.3 Serial Interface with RS-422
This interface typ requires the signal lines.
$ Pin
1 Protective Ground (PG)
$
3 Receive Data (RDA)
$
9 Send Data (SDA)
$
10 Not Send Data (SDB)
$
18 Not Receive Data (RDB)
Standard Connection
Protective ground (PG) connected either to host or printer
Note:
Appendix A System Interface Description
A-7