I just got my new ethernet shield (http://www.ebay.com/itm/300581750863?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649). I tried everything I can do but, nothing seems to work. First of all, I cannot upload any sketches while shield is plugged in to the arduino because serial port changes from /dev/ttyACM0 to /dev/USB0 and it says ttyACM0 is not available should I try USB0. I say OK try it but it cant upload the sketch via USB0. I upload a web client sketch while shield is unplugged, it uploads fine, then I plug the shield in and restart arduino, I cant event open serial window because it automatically changes ACM0 to USB0. http://www.arduino.cc/en/Guide/Troubleshooting#upload here it talks about a patch, idk if it is relevant to the subject but I couldn't install it either. Is there any solution via any patch or terminal ?
Well, it seems I have the same problem with the people who complains about ethernet shield flooding the serial port so I can't upload a sketch. I have removed all Serial.print(); statements now it is fine, I can upload sketches but the problem is I tried every example in the Ethernet Library but my shield does not seem to transfer or receive any data over internet. I found out that only green light on the RJ-45 jack is steadily on, but the yellow one does not even get on for once. I'm currently debugging w/LEDs since I can't use Serial port. + I do not know my wiznet's MAC Address, in ethernet references of Arduino it says older arduinos takes whatever MAC value you write but the newer ones have a label or sticker kinda thing on them but there is not! I want to know if my hardware is faulty or I can't connect to the internet because I'm just giving a random MAC address to my arduino.
MAC addresses which are provided in Arduino Examples were not genuine I guess. I have looked up for verdor part of the MAC address for Wiznet company and note it down (first 6 digits) then I made up the rest randomly and it worked both SD and Ethernet are fully functional.
I bought another shield that is the exact one you do. I tried the web server example but I could not ping it. I am not sure if mac address could be the issue. I pretty much tried everything, from change ip address to resetting before running, etc.. But what is the mac address you found and used? Did you ever have trouble with the web server example?
I found out that only green light on the RJ-45 jack is steadily on, but the yellow one does not even get on for once.
I also notice this on my shield and I initially thought this could be a defect. But if it's working for you then I feel a bit better.