Paradise P300 specifications Eurocom D/1 interface `G` operation, Links, All links settings are

Eurocom D/1 interface `G` operation

The Eurocom `G` interface uses transformer coupled differential combined clock and data signal which is diphase coded. The amplitude is ±1.0V (ie 2.0 V peak to peak). The lines are of 130 impedance, and the centre tap of the line coupling transformers may either be grounded, or left floating.

The Eurocom `G` interface will operate at either 16kbps of 32kbps only, NO OTHER DATA RATES are supported. The modem will generate a configuration error if configured for data rates outside the range 16-32kbps, but note that only 16kbps & 32kbps are valid rates for operation of the Eurocom interface. For example configuring the modem for 20kbps will NOT cause an error, but the Eurocom interface will not function correctly at this rate.

Min			25 pin		Link to ground
	Signal Description				centre tap of
Req		A		B
					transformer
DATA CIRCUIT TOWARDS MODEM (TX)
	Clock/Data In	24		11	LK 3 *
DATA CIRCUIT FROM MODEM (RX)
	Clock/Data Out	23		10	LK 6 *
COMMON LINES					S
	Ground to Activate Eurocom `G` at 16kbps		20		n/a
	Ground to Activate Eurocom `G` at 32kbps		14 AND 20		n/a
	Do Not Connect		12		n/a
	Signal Ground	2, 7, 13, 15, 22, 25			n/a
U	Shield/Protective ground		1		n/a

* Links

All links settings are:

Centre tap grounded: 1-2 (link `up` with the PCB legend the right way up) Centre tap floating 2-3 (link `down` with the PCB legend the right way up)

The typical configuration would normally be to ground the outputs, and leave the inputs floating ie: Link 6 in pos 1-2 (up), and link 3 in pos 2-3 (down)

This provides protection by ensuring the signal levels remain close to ground potential (as might happen if both inputs and outputs were floating), but avoid any ground currents between distant locations (as might happen if both inputs and outputs were grounded).

P300H P300 Series Modem Installation and Operating Handbook Page 178