RS232 DB9 Serial Loopback for CheckIt
The PC loopback plug is a useful diagnostic tool. The loopback plug connects serial inputs to serial outputs so that the port may be tested. There is more than one way to wire up a loopback plug - but this is the most common. Used to verify that a port is working. This one works with CheckIt.
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DB9 pin D-SUB male (at the computer) |
Name | Pin | Pin | Name |
---|---|---|---|
CD | 1 | 6 | DSR |
CD | 1 | 9 | RI |
RXD | 2 | 3 | TXD |
DTR | 4 | 6 | DSR |
RTS | 7 | 8 | CTS |