Rockwell Automation 1771-DMC_DMC1_DMC4_DXPS Control Coprocessor User Manual - Manual (Page 127)

Chapter 8
Interpreting Fault Codes and Displays
8-2
The following tables provide information for the LEDs on the
control-coprocessor main module and the serial expander module.
LEDs on the Main Module
LED Color Indication
CPU
green valid processor cycles are occurring
CPU
red a fault condition
COMM0 and COMM1
green receiving data
COMM0 and COMM1
(except RSĆ485) ¬
red transmitting data
(except RS 485)
off idle
¬
solid green idle
COMM1 (RSĆ485 only) ¬ flickering green receiving data
off
transmitting data
BATT
off good battery
BATT
red replace battery (or no battery installed)
¬ When nothing is attached to the communication port, the indicator is always green.
When a device is connected to the communication port, the indicators are lit/off as
indicated above.
LEDs on the Serial Expander Module
LED Color Indication
COMM2 and COMM3
green receiving data
COMM2 and COMM3
(except RSĆ485) ¬
red transmitting data
(except RS 485)
off idle
COMM2 and COMM3
solid green idle
COMM2 and COMM3
(RSĆ485 only) ¬
flickering green receiving data
(RS 485 only)
off transmitting data
¬ When nothing is attached to the communication port, the indicator is always green.
When a device is connected to the communication port, the indicators are lit/off as
indicated above.
Status for LEDs