ADTRAN 1200051L2, 61200051L1, 1200051L6, 1200051L5 user manual DTE Indicators, Indicator Definition

Chapter 1. Understanding ISDN and the ISU 2x64

The ISU 2x64 allows the user to migrate ISDN into existing net- work services and data communications equipment. The ISU 2x64 interoperates with ISU 128s, Switched 56 DSUs, various ISDN terminal adapters, and BONDING inverse multiplexers (for example ASCEND®, PROMPTUS, and Teleos®). For instance, in a video conferencing application, this compatibility allows the ISU 2x64 to interoperate with networks utilizing two Switched 56 DSUs.

The ISU 2x64 front panel accommodates a 2-line by 16-character LCD display. Seven LED indicators monitor data flow and dis- play the status of key DTE interface leads (see Table 1-A and Fig- ure 1-2). A front panel keypad supports configuration, test modes, test status, and dialing.

	Table 1-A
	DTE Indicators
Indicator	Definition
RS	Request to Send. Indicates the DTE is ready to
	transmit.
CS	Clear to Send. Indicates the ISU 2x64 is ready
	to transmit.
TD	Transmit Data. On when the DTE is transmitting
	to the ISU 2x64.
RD	Receive Data. On when the ISU 2x64 is receiv-
	ing data from the far end.
CD	Carrier Detect. On when the ISU 2x64 is con-
	nected to a remote unit.
TR	Data Terminal Ready from DTE. On when DTR is
	active at DTE interface.
SR	Data Set Ready.

61200051L1-1D ISU 2x64 Dual Port ISDN Service Unit User Manual 3