Cabletron Systems CSX200 Table A-13 provides pin assignments for the X.21 interface cable

Appendix A: WPIM Cable Specifications

X.21

Table A-12shows the connector number, cable assembly description, and connector type.

Table A-12 X.21 Interface

Connector Number	Cable Assembly Description	Connector Type
1	EIA-530A ALT A to X.21	Sub DB 26-pin male
2		DB-15 pin male

Table A-13provides pin assignments for the X.21 interface cable.

Table A-13 X.21 Interface Cable Pin Assignment

Connector 1 EIA-530A ALT A						Connector 2 X.21
				PAIR
MNEMONIC	DIRECT	NAME	PIN		PIN	NAME		DIRECT	MNEMONIC
	TO							TO
BA	DCE	Transmit Data A	2	A	2	Transmit A		DCE	T
		Transmit Data B	14		9	Transmit B
BB	DTE	Receive Data A	3	B	4	Receive A		DTE	R
		Receive Data B	16		11	Receive B
CB	DTE	Clear to Send A	5	C	5	Indication A		DTE	I
		Clear to Send B	13		12	Indication B
CA	DCE	Request to Send A	4	D	3	Control A		DCE	C
		Request to Send B	19		10	Control B
		Transmit Signal Timing A	17		6	Signal Element
		Receive Signal Timing A	15			Timing A
DB	DTE			E				DTE	S
		Transmit Signal Timing B	9		13	Signal Element
		Receive Signal Timing B	12			Timing B
		SHIELD	1				DRAIN
AC		DTE Common	7		8	Signal Ground			G
AB		DCE Common	23

A-8 CSX200 Installation Guide