Patton electronic 2635, 2621 manual X.21 DB-15 Connector, Control - B, Signal Timing - A

Models 2603, 2621, and 2635 Getting Started Guide D • IPLink Physical Connectors

X.21 (DB-15 Connector)

The X.21 interface in the Model 2621 may be configured for either DTE or DCE. Default is DCE.

Table 10. X.21 Interface (Model 2621)

Pin No.	Circuit		Signal Name				Direction
1	G		Signal Ground or Common				-
					Return
2	T		Transmit (Data)-a				from DTE
3	C				Control-a		from DTE
4	R		Receive (Data)-a				to DTE
5	I			Indication-a			to DTE
6	S		Signal Timing-a				to DTE
7	-				-		-
8	Ga		DTE Common Return				-
9	T		Transmit (Data)-a				from DTE
10	C				Control-b		from DTE
11	R		Receive (Data)-b				to DTE
12	I			Indication-b			to DTE
13	S		Signal Timing-b				to DTE
14, 15	-				-		-
		Transmit – B		9	1 Frame Ground
					2	Transmit – A
		Control – B		10
					3	Control – A
		Receive – B		11
					4	Receive – A
	Indication – B			12
					5	Indication – A
	Signal Timng – B			13
					6	Signal Timing – A
				14
					7
				15
					8	Signal Ground

Figure 85. X.21 DB-15 connector

Serial port 127