Ryan Nazaretian

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9 years, 7 months ago.

Avago fiber optic transceiver & mbed LPC1768

I'm trying to use the Avago AFBR-5803Z with my mbed LPC1768. I have a fiber connection to a TP-LINK MC100CM. With two TP-LINK MC100CMs conntected over fiber, with one ethernet connection going to my mbed application board and one to my laptop, I can communicate. However, if I wire the AFBR-5803Z to the mbed directly, it does not create a link. Below is a diagram of the wiring I'm using right now.

http://i.imgur.com/9IJxWVW.png

Can anyone see anything wrong with what I'm doing?

1 Answer

Peter Drescher
9 years, 7 months ago.

See Figure 7 of the datasheet. You will need a Termination Circuit.

It is my understanding of the mbed LPC1768 that it has built in termination. See sheet 4/5 of the mbed LPC1768 Schematic.

posted by Ryan Nazaretian 09 Apr 2015

But the termination is different. I would test it with the termination from figure 7. You have to desolder the 49.9R from the mbed board.

posted by Peter Drescher 09 Apr 2015