Pages: [1]   Go Down
Author Topic: Reading from a SD Card without a shield  (Read 2365 times)
0 Members and 1 Guest are viewing this topic.
Offline Offline
Newbie
*
Karma: 0
Posts: 3
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

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This looks like what i want, but out of date and with a more complex library.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.
Logged

0
Offline Offline
Edison Member
*
Karma: 64
Posts: 1636
Arduino rocks
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

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.

Logged

Smithfield, Rhode Island
Offline Offline
God Member
*****
Karma: 3
Posts: 843
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

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

Logged

0
Offline Offline
Full Member
***
Karma: 5
Posts: 238
Arduino rocks
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

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
Logged

Smithfield, Rhode Island
Offline Offline
God Member
*****
Karma: 3
Posts: 843
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

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.
Logged

Pages: [1]   Go Up
Jump to: