Problems with Seeeduino Mega and SD cards

Hi

I just got a hold of a couple of SD cards(one 256mb and one 1gb non sdhc, both tested with fat16 and fat32), but i am having some troubles on how to get my arduino to talk to them. I tried with this lib: http://code.google.com/p/sdfatlib/ and this schematic: http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1206874649/0 Instead i use some 10kohm and 20kohm resistors, because thats what i had on hand.

But i couldnt get i to work, either with the normal pins 8-13, and the 53 to 50 pins, i also tried to swap the pins around to see if my wiring was wrong, but that didnt help either.

The error i get is "SD Card Error 1", no matter what sd card i use, and no matter what example i use.

I hope someone can give me some tips on what i might do wrong. BTW, can i just flick the 3.3volt switch on the Seeeduino mega, instead of using the resistors?

Best Regards Morten

BTW, can i just flick the 3.3volt switch on the Seeeduino mega, instead of using the resistors?

No, the 3.3v/5v power selection switch on the Seeeduino Mega was a flawed design and should not be used in other then the 5vdc position. see bullet #5 in the product discription. This switch was to change the AVcc voltage so that the analog inputs would have a 0-3.3vdc range instead of the standard 0-5vdc range, however the AVR spec sheet says that AVcc must be the same as the chips Vcc voltage.

http://www.seeedstudio.com/depot/seeeduino-mega-fully-assembled-p-438.html?cPath=27

Lefty

Okay, nice to know, and thank you for the quick answer, i was just about to try it, but now i know it wont help.