Digi 90000278_B - Manual (Page 9)

Digi One EM Hardware Reference 9
Connectors: Power and Serial Interface (P4)
The Digi One EM has a single 12-pin, serial interface port
(labeled P4) that supports EIA-232 (TTL levels only), data
rates up to 230 Kbps and full-modem control. The following
figure helps you locate pins, and the table helps you identify
which signal uses each pin.
Pin Signal Name Description
1
+5VDC to
+9VDC (input
only)
Input power to Digi One EM
2 GND Reference Ground for input power
3 RxD Receive Data (input)
4 TxD Transmit Data (output)
5 RTS Request To Send
6 DTR Data Terminal Ready
7 CTS Clear To Send
8 DCD Data Carrier Detect
9 DSR Data Set Ready
10 RST~ Reset
11 Reserved Not used
12 Reserved Not used