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Topic: Reading from a SD Card without a shield (Read 2514 times) previous topic - next topic

Jakeyboy

I am looking for the easiest way to read from an SD card without a shield. I would like to read a text file into a string or serial. Preferably using the SD Card Library shown here.

http://arduino.cc/en/Reference/SD

This looks like what i want, but out of date and with a more complex library.
http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1206874649/8

Please help and enlighten me of the best way to accomplish this.

fat16lib

There a lots of SD/MicroSD modules.  These modules are much more reliable than circuit using resistor level shifters.

https://www.adafruit.com/products/254

http://www.gravitech.us/sdcaad.html

http://www.gravitech.us/micaad.html

I would avoid SD modules with resistor level shifters.  Many SD cards now have edge detectors and expect faster, 10 ns,  rise times on SPI signals.  Resistor level shifters are marginal for these SD cards.


skyjumper

Ya know, I just bought some of these and now they seem to be out of stock. I hope they get stock soon:

http://search.digikey.com/scripts/DkSearch/dksus.dll?vendor=0&keywords=497-1017-1-ND


wwbrown

DigiKey shows they do not stock that item so it is a special order.  Would these http://search.digikey.com/us/en/products/SN74HC125DR/296-1192-1-ND/404905 work.

wade

skyjumper

That part is discontinued. There are several pin compatible substitutes but the only one I could actually locate for small quantity purchase that is completely compatible (that is, just swap it in) is this one:

http://www.futureelectronics.com/en/Search.aspx?dsNav=Ntk:PartNumberSearch|MC74AC125DG|1|,Ny:True,Nea:True

I have no idea why Digikey and Mouser don't carry it.

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