I have recently purchased an Ethernet PRO Arduino and also picked up an SD shield the other day at Micro Center; THIS IS A GREAT PARTNERSHIP BY THE WAY! But none of the half dozen micro SD cards I had worked. So I soldered a regular SD socket to the board and wired it up. A regular SD 256MB card worked fine. I also recently picked up an Adafruit data logger shield and my 256MB card works but the two 2GB Adafruit cards didnt work. So I tested both the SparkFun and Adafruit shields with my Dad’s UNO and every card works fine…
So I was wondering if anyone else was having similar issues? I know the Adafruit data logger shield wont work with the Ethernet Pro since they share CS pins (pin 10) but the SparkFun SD shield should. How would anyone suggest I test to see if the W5100 chip is interfering with the SPI communications with the SD card or the logic rise/fall times?
I asked tech support at SparkFun and got this reply:
It looks like this board is old enough that its pre-SPI-release fix (yes, I made that word up). That is most likely your issue. Try using the uSD shield without ever initializing the W5100 and see if it works. If so that is most likely the problem. Check out the solution to the problem on the Wiznet page describing SPI use. The Sen pin isn’t really broken out, but it is attached to a pull-up resistor and a solder jumper, you should be able to attach the solder jumper to an I/O pin pretty easily. Let me know if this works or if you have any other questions.
There is a solder jumper on the bottom of the PRO Ethernet board labeled “PROG”. One side of the solder jumper is tied to the SEN pin on the W5100 chip and the other to the ground plane. I tied a wire to this and pulled it low temporarily; this solved all my SD card access issues.
Figured I’d post this for anyone else having problems… Id like to put an inverter on the thing and drive it from pin 10 ~CS for the W5100 chip but that seem a bit much to save a single IO pin…