RadioShack sells the Seeed Studio SD Card Sheild 3.0 and the Arduino Mega 2560 rev 3 together on the same shelf, plus the former advertises itself as Arduino compatible, so, silly me, I just assumed they would work together.
When do you actually find out that they're not? Well, you take the little card that was hidden in the packaging, go to the website they tell you to:
And find this phrase:
"Do not compatible with Mega"
So basically their "Arduino Compatible" label is just BS. I feel completely lied to, and it's safe to say I won't ever purchase another Seeed product.
Anyways, someone else on these forums provided these directions for how to make the Seeed work with my Mega two years ago:
bosduino: This isn't really a clean solution, but it works as long as you don't plan to stack any additional shields on top of the SEEED SD shield:
There are two different options. a) is safer, b) will involve clipping some of the pins on the SD shield.
1) Connect all headers on the "analog side" (Analog and Power) using a separate set of headers to create space between the boards 2) use a jumper wire to connect Mega Pin 10 to SD pin 10 3) use a jumper wire to connect Mega Pin 50 to SD pin 12 4) use a jumper wire to connect Mega Pin 51 to SD pin 11 5) use a jumper wire to connect Mega Pin 52 to SD pin 13 6) Upload the sketch and try it.
And here's b) (BEWARE! There's no way back if you mess up!):
1) Trim all digital pins off the SD shield EXCEPT pin 10 2) Stack the SD shield onto the Mega 3) use a jumper wire to connect Mega Pin 50 to SD pin 12 4) use a jumper wire to connect Mega Pin 51 to SD pin 11 5) use a jumper wire to connect Mega Pin 52 to SD pin 13 6) Upload the sketch and try it.
I'd like to just run the CardInfo Example code.
Here's the part that I wonder about:
Is it possible to just change some variables in the example code so that it'll work with my Mega? I feel like exposing these variables was a rather recent change that opens up the SD library to be used with a wider variety of SD card readers. Namely, I noticed that:
chipSelect can be changed. pinMode accepts a variable.
So… is there some way I can utilize those variables to make the Seeed SD Card Shield work for me, or is my best option to add jumper cables as suggested in the post I quoted?