Onboard LEDs

The EM203 features four onboard status LEDs. The LEDs are strategically positioned on the edge of the module's board. Your product can have a small window or opening on its cover to make the LEDs of the EM203 visible from the outside (as shown on the drawing in the Ethernet Lines and Jack/Magnetics Data ). When the EM203 is used in combination with the RJ203 module, the status LEDs are visible through a transparent portion of the RJ203's housing.

em203_onboard_leds

Onboard LEDs have the following function:

Yellow Ethernet status LED is turned on when the EM203 links with the hub at 100Mb. The LED is off when the link is established at 10Mb.
Green Ethernet status LED is turned on when "live" Ethernet cable is plugged into the Module. The LED is temporarily switched off whenever an Ethernet packet is received.
Red and green status LEDs are under the control of EM203's firmware.

The EM203 also has four LED control lines that allow you to add external LEDs in parallel with the onboard ones.