Digi 90000278_B manual Connectors Power and Serial Interface P4

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
	+5VDC to
1	+9VDC (input	Input power to Digi One EM
	only)
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

Digi One EM Hardware Reference 9