The Back Story...

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So I recently had my first experience with buying knockoff electronic development hardware from a sketchy source...  It's kind of like an online market with various sellers you can buy from.  I spent about 100 bucks and, all-in-all, it was a good experience, as I saved about 50% total from what these similar items would have cost otherwise.  However, I thought I'd write about the couple of items which were not so good....

Among all the items purchased was a TFT01-3.2, a 3.2" TFT touch screen LCD with a full-size SD card socket.  The item was remarkably similar to itead studio's ITDB02-3.2S.   All worked fine and dandy with the Arduino MEGA2560 (also part of the overall purchase) until I tried testing out the SD card interface with one of the Arduino IDE's examples.  The terminal kept returning the message "SD card not available" or something to that effect.  So a lot of tracing through Arduino Mega2560 schematics, TFT01-3.2 shield schematics and a lot of head scratching finally revealed a mistake in the pinout for the U3 connector on the TFT01-3.2 shield adapter board.  The U3 connector had the SCK and MOSI pins swapped (see below).
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Arduino Mega2560 schematic
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Arduino Mega2560 board - front view
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TFT01-3.2 shield schematic
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TFT01-3.2 board - front view

The Fix...

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So the fix for this problem was pretty easy as you can see from the picture.  Not the best soldering job, but I tested it out with the same Arduino sketch as before and all worked fine.  



Conclusion

This took me about an hour of tracing through the three related schematics and physical board views all while being interrupted about every ten minutes by mini me's.  If you're a noob, this likely would have taken a lot longer, especially if you resort to forum posts and waiting for replies with solid answers.  Not to mention if you lack the soldering skills (oh yeah, that pic above is some true soldering skill - lol).  So paying more for known good hardware would have saved me a little time and maybe saved a newbie a lot of time (or saved them from giving up).  However, if you don't mind digging in and think you fair pretty well at troubleshooting problems, then you may be able to save some coin by going the route I did.
 


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