AT&T DataPort PCX Modem User Manual page 39

Front Panel Status Lights
Table A-1. LED Descriptions (2 of 2)
LED
Label Description
TR Terminal Ready. When ON, the computer is attached and
ready to send data to or receive data from the modem. Note
that if the &D command is set for Ignore (&D0), then this LED
is always ON.
If the correct COM port is not selected, this LED will not light.
The &D command (DTR Action) must be set for standard EIA
RS-232 operation (&D2) for the LED to function this way.
When Off, data cannot flow between the two devices.
This LED follows the status of the DTR signal, Pin 20 of the
EIA RS-232 interface.
MR Modem Ready. When ON, the modem is ready to send data
to or receive data from the computer. This LED follows the
status of the DSR signal, Pin 6 of the EIA RS-232 interface.
A-2
Issue 2 July 1995