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[Reply #180 on:]

How do i use this? all of the libarys dont seem to want to work with the original schematics. i have this board all done and made and wired up as the diagram is

[Reply #181 on:]

This one seems cool, although my bad soldering skills will mess up everything

[Reply #182 on:]

I'm excited at the prospect of doing some datalogging with the arduino for my temperature control experiment which is already working, but the wiring/breadboarding to get the hardware solution in this forum going is a little daunting. I'd prefer to spend a few bucks and get something already built, and fool around with the software instead.

I saw the ethernet shield with sd reader, but it's kind of expensive at $45. The sparkfun $15 shield for sd cards had quite a variety of bad reviews.

Does anyone in this forum have suggestions for a reasonably inexpensive, but not particularly hardware challenging way to get SD cards (or microsd, or whatever) working?

[Reply #183 on:]

I am using the Gravitech microsd card in my project.

http://store.gravitech.us/adapterboards.html

[Reply #184 on:]

Hello everyone,

I'm new to the forum so I'd like to first say hi to everyone.

I recently began experimenting with wiring to the SD card on a breadboard and I had a thought. Why not connect the ground pins on the SD card to a 1.7v supply and use the 5V line for VCC? This way the card will see a 3.3V supply and see 3.3 level signals from the arduino.

I tried this and it seemed to work out fine. When I initially used the voltage dividers (since I didn't have the buffer IC), I started to get bad data after a certain speed because of the resistor delay. This was eliminated when I used the 1.7v supply. I am able to write 6 channels of analog data at 200 Hz. I haven't tried anything faster yet.

My question is does anyone think this is damaging the SD card? I've already ordered the buffer ICs but if this method works fine over a long time then I won't use them.

Thanks

[Reply #185 on:]

Hello everyone! I have an arduino mega(atmega2560)+ ethernet shield+sd card http://www.arduino.cc/en/Main/ArduinoEthernetShield

To make the lib sd_raw work on my mega i added the following lines
in sd_raw_config.h where is checking for platform definitions.

Code:

#elif defined(__AVR_ATmega2560__)
      #define configure_pin_mosi() DDRB |= (1 << DDB2)
    #define configure_pin_sck() DDRB |= (1 << DDB1)
    #define configure_pin_ss() DDRB |= (1 << DDB0 )
    #define configure_pin_miso() DDRB &= ~(1 << DDB3)

    #define select_card() PORTB &= ~(1 << PB0)
    #define unselect_card() PORTB |= (1 << PB0)

without this i get error

Code:

   #error "no sd/mmc pin mapping available!"

i hope that help arduino atmega2560 users