Connector pin assignments and a description of their respective interface signals are shown in the table below.
Signal pin | Signal |
|
| Direction | Description | |||
1 |
|
|
|
|
|
|
|
|
| FG |
|
|
|
|
| Chassis around | |
|
|
|
|
|
| |||
2 |
| TXD |
|
| OUT | Transmits data for | ||
|
|
|
|
|
|
|
| XON/XOFF |
|
|
|
|
|
|
|
|
|
3 |
| RXD |
|
| IN | Receives data | ||
4 - 6 |
| NC |
|
|
|
|
| Not connected |
|
|
|
|
|
| |||
|
|
|
|
|
|
|
|
|
7 |
| SG |
|
|
|
|
| Signal ground |
|
|
|
|
|
| |||
|
|
|
|
|
|
|
| |
| NC |
|
|
|
|
| Not connected | |
|
|
|
|
|
| |||
11, 20 |
|
|
|
|
|
|
|
|
| DTR |
|
| OUT | Indicates whether or not | |||
|
|
|
|
|
|
|
| the printer is ready to |
|
|
|
|
|
|
|
| receive input data. If data |
|
|
|
|
|
|
|
| input is not ready, DTR = |
|
|
|
|
|
|
|
| “MARK”. |
|
|
|
|
|
|
|
|
|
| NC |
|
|
|
|
| Not connected | |
|
|
|
|
|
| |||
|
|
|
|
|
|
|
| |
| NC |
|
|
|
|
| Not connected | |
|
|
|
|
|
| |||
|
|
|
|
|
|
|
|
|
The column heading “Direction” refers to the direction of signal flow from the printer.