### DB-25 Software Handshaking (XON/XOFF)

Simple Terminal/Printer Cable

DB-25 Female (Digi End) |  | DB-25 Male (Peripheral)
--- | --- | ---
Signal | Pin | Pin | Signal
TxD | 2 | connected to | 3 | RxD
RxD | 3 | connected to | 2 | TxD
SG | 7 | connected to | 7 | SG
GND | 1 (or shell) | connected (via shield) to | 1 (or shell) | GND

This cable is a three-wire null modem cable. Transmitted Data on one end of the cable is connected to Received Data at the other end, and vice versa.

The male DB-25 end can be plugged directly into most serial terminals and printers without any adapters. The female DB-25 end plugs directly into one of the DB-25 connectors on the fan out cable or connector box assembly.

In most cases, serial terminals and printers need only a three-wire connection. Digi device driver software supports XON/XOFF (software) handshaking, so the only signal lines necessary are Transmitted Data (TxD), Received Data (RxD), and Signal Ground (SG).

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