I use the ENC28J60 MAC+PHY ethernet controller (datasheet) in a fairly standard setup as shown in the schematics below.
I can talk to the ENC via SPI, but I cannot get a link-up when I plug in an ethernet cable. I am looking for suggestions how to narrow the error down.
My considerations so far:
- I checked all electrical connections and they seem ok.
- The MagJack is of this type. I have used a different one (this one) on a different, but working ENC setup. As I have not used this MagJack type before, it raises my suspicions. However the datasheet looks ok for me.
- The crystal is of this type. The ENC datasheet says it requires the use of a "parallel cut" crystal. I am not sure if my crystal fulfills this requirement.
- I use hand-soldered 0201 size load capacitors. Crazy, I know. The solder joints look ok. But as I cannot test them and they are so small, I suspect them as well.
I am not sure if the fact that I can talk to the ENC via SPI means that the crystal and the load caps work ok. If yes, then the MagJack would be my prime suspect.
So my next steps would be 1. replace the MagJack, if that fails, 2. replace crystal and load caps.
Any suggestions on more probable error causes, or ideas how to narrow the error down would help me greatly.
Notes on the schematics:
- VCC is +3.3V.
- I connected LEDs for LED A and B tied to GND, not shown in the schematics.