Hi, I have a problem that I'm hoping someone here can solve. Simply put, I can't get any SD card interface to work at all. I've tried 3 different boards, 2 of them the blue ones that are all over ebay at the moment that take full size SD cards, and 1 is a micro-sd slot built into a 1.8" LCD. All 3 of them fail to initialize the card when I run any of the example SD sketches. I've tried with multiple SD cards, including an old 256mb, a micro-sd, a regular 2gb and an SDHC card. All have the same effect.
I've redone the wiring multiple times but I can't find any error in the connections, here is the current state (arduino on the left):
POWER
3V3 goes to +3.3
5V goes to +5
Gnd goes to GND
DIGITAL
4 goes to CS
11 goes to MOSI
12 goes to MISO
13 goes to SCK
GND goes to GND (there are 2 GND pins on the card board)
I've tried it with 2 sets of cables, with and without external power (9v from a transformer plug), I've checked that the card clicks into place, and still get the same error. I'm still learning to use the arduino so is there something simple I've missed? If it makes any difference I'm using a Duemilanove, female-female breadboard wires, and a block of right angled interface pins to make the I/O ports compatible with the wires. I can post a photo of the setup if it would help.
Thanks in advance for any advice or suggestions you can give.
What are these "all over ebay" card readers, which I don't have? Are they shield form factor or not? Are you sure that both the hardware and software are using pin 4 as chip select or maybe pin 10 instead, which is just as popular?
hi, thanks for the reply, I can't find a model number for the card reader but it looks just like this one: **Hobby Components UK** Arduino compatible SD Card Module | eBay
(I hope it's ok to post links to ebay here, if not apologies in advance). It's not a shield, the board is just a bit larger than the SD slot.
I've got an LCD plugged in at the moment and noticed the CS pin on that is pin 10, so I'll try changing it to 10 on the card slot (I take it I can just edit the sketch and move the wire?)
There is not enough information from the seller on this device. I suspect the device has no level shifter. SD cards use 3.3V logic and Arduino UNO uses 5V logic. A logic shifter is needed on all these pins: SCK MISO MOSI.
I don't mind ebay links as long as they are there to make things clear, instead of say repeatedly mentioning someone's product in an inappropriate way. In your case that link is necessary.
Are there anything on the back side of the SD card module? The front side only has resistors and a voltage regulator. Please DON'T connect arduino 3.3V to this module's 3.3V. That pin is probably an output from the onboard 3.3V regulator.
The back of the board only has the maker's name and website, LC Studio. I'll try reformatting the card.
liudr:
Please DON'T connect arduino 3.3V to this module's 3.3V. That pin is probably an output from the onboard 3.3V regulator.
Too late, but thanks for the warning. I tried it with just the 5v at first, when it didn't work I plugged in the 3.3v as well. The arduino hasn't shown any sign of damage but I'll keep the 3.3v disconnected now.