I am having troubles accessing a custom Atmega2560+W5100 board from the network and would appreciate any tips on what could be wrong and how to proceed on getting it to work properly.
I am currently trying to combine the Arduino Mega 2560 and Arduino Ethernet Shield (+ some other circuits connected to the analog and digital pins of the Atmega2560) onto one single PCB.
I started with the schematics of the Arduino Mega 2560 and the Ethernet Shield, combined them into one (in EAGLE) and connected the MISO, MOSI, SCK, SS and Digital Pin 10 nets just as the ICSP header of the Shield usually does. The MISO, MOSI and SCK lines between the Atmega2560 and the W5100 are not directly connected but can be connected with jumpers. You can find the schematic (without the other circuits I mentioned which should not matter anyway) attached to this post.
The Arduino Mega 2560 part of the board works fine. I bought the PCB from Oshpark, populated it and can program the Atmega2560 (see attached picture). It responds and executes programs as desired.
However, the Ethernet Shield part does not work as I hoped.
In more detail: I think the W5100 chip is running correctly. It lights up the LINK and 100M LEDs when I plug in an Ethernet cable to the RJ45 port. I can also call the Ethernet.begin(mac, ip) function and get back the correct IP when calling the Ethernet.localIP() function. I assume that means the communication between the Atmega2560 and the W5100 is working?
However, I cannot ping or somehow else address the board from the network. (I’ve tried the router with a normal Mega+Ethernet Shield setup and it works.) I am using only the very basic code from the Ethernet library examples and have quite some experience with using the original Ethernet Shield already.
The one thing I am suspicious about is the RJ45 connector. I used one without magnetics, since I could not get one with magnetics. Does anyone have any experience, if this might result in the board not being addressable over the network?
I know one should use an RJ45 connector with magnetics, but could not find one anywhere. Anyone has some experience with these connectors and can point me to somewhere, where I can buy them (I am based in Austria)? It seems impossible to get one equivalent to the one used in the Arduino Ethernet Shield…
It would be great if someone can share some experience with building a W5100 Ethernet Shield and give me some tips on how to check if everything is working. After trying for days, I am getting rather frustrated with the chip and would really appreciate any input on how to check what is working and what could be the cause of the problem of not being able to reach the chip from the network.