3Com 56K Command Reference Manual page 181

H
V LED
IEWING
This appendix explains how to view the twelve LEDs on the front of your
Business Modem.
This LED Status
Alert On
Flashing
Off
Power On
Off
Fax On
Off
ARQ On
Off
AA On
Blinking
Off
OH On
Off
TD On
Off
RD Flashing
Off
MR On
Flashing
Off
S
Means your Business Modem
Has detected a firmware dowload error
Firmware update in progress
Normal operation
Is switched on
is switched off
Is currently configured for fax operation
is not currently configured for fax operation
Is making a data connection using an error control
protocol
Is making a data connection without using an error
control protocol
Is ready to accept calls
Has detected an incoming call
Is not ready to accept calls
Has control of the line
Does not have control of the line
Is transmitting data
Is not transmitting data
Is sending data to your computer
Is idle
Is powered on and ready or is receiving RS232 DSR signal
Is retraining with a remote device or is in Test mode
Is powered off