Hello, I am using the W5100 Ethernet shield with the Arduino Uno. I have uploaded the DHCP Address printer code which comes pre installed in the examples. I seem to have a problem connecting to the network.
None of the lights other than the FULLLD led on the shield blink after connecting the ethernet cable. However if I connect the sheild to my PC through a LAN cable and monitoring it using Wireshark I see that all lights blink and there is some communication happening between the PC and the shield.
I tried to debug this issue by placing some Serial.print statements in the ethernet library and i found out that the arduino reads back 0xFF when it tries to search for a socket(value of SnSR register in W5100). Since it does not get a socket it cannot start the DHCP communication.
On further investigation I found that this is the case with the other registers as well. Always the value read back is 0xFF even though a different value is written to the register just before reading.
Since i do not have a SPI protocol sniffer i am unable to determine if this is some SPI issue. I have disabled the SPI for the SD card on the ethernet sheild but still this problem persists. Is this a HW issue with my Uno or with the Ethernet shield. It is difficult to determine physical connections to the chips since they are SMD packages.
Has anyone else faced this problem? and if you have a solution please let me know.