Reading SD card directly in PC

Hello everyone,

I am going to use Arduino and a SD Card breakout board from Sparkfun (https://www.sparkfun.com/products/544). I wanted to know if it is possible to read the data stored in the memory card directly in your pc without disconnecting it out from the Arduino board. If this is possible what kind of extra circuit do i need to have in between the Pc and the SD card?

My SD card will be inside a device which will take more than an hour to deassemble. So when I need to check the data I just want to connect it to the sd card via a connector and directly view it in the PC, is something like this possible?

any help/suggestion is appreciated.

You would have to write a sketch for the Arduino which completely emulates a USB mass-storage device. I've never seen an example of this online so it's either impossible or just very difficult. To appear as a disk drive for Windows, you need to have a lot of capability in the device. What happens when Windows tries to 'format' your disk? What commands does it send and what are the proper responses? I'm sure the specification for this is more than just one book.

The easier way is to write your sketch so that it will accept commands over Serial. Connect your device to the PC and use the serial monitor to talk to it. Create a command to download all the data. Then copy-paste from the serial monitor to a spreadsheet or document. Tab-separated data (with the '\t' character) works very well with Excel.

For more cleverness, write a program for the PC, using Processing, C or whatever, which will do the same thing.

So when I need to check the data I just want to connect it to the sd card via a connector and directly view it in the PC, is something like this possible?

Yes.

The Filedump programme included in the SD section of the examples in the iDE will do this. You can send the filename and receive the file using a proper terminal programme, not the serial monitor. I use RealTerm but there are others, all freebies. No additional circuitry required. You might find it more convenient it download via bluetooth, rather than use a cable. This is what I do, and download to the phone.

I have toyed with a circuit design using this chip to switch between giving the PC control of the SD card or giving the Arduino control of the SD card.
Haven't made one up yet. Software would be a little complicated as it seems the SD cards needs to be reset between accessing it in SPI mode (arduino) and in parallel data mode (PC) and vise versa.

Like everything, just not enough hours in the day to try it all.

VUB300 Datasheet-v14.pdf (406 KB)