3g/gps shield store in sd

djo54150 · **Joined:** Mon Apr 23, 2012 1:45 pm **Posts:** 34

how to store data on the sd? but it ' s no picture or sound or video

i need use sd lib?

libelium-dev · **Joined:** Mon Sep 28, 2009 11:06 am **Posts:** 2057

Hello djo54150:

For store data into the 3G module you can use AT+CTXFILE and AT+CRXFILE. This commands use the Xmodem protocol in order to send data between Arduino and the 3G module.

Regards

vellamy · **Joined:** Mon Jun 04, 2012 12:02 pm **Posts:** 18

Hi,

Is it possible to take data from the SD of the 3G module and then process that data in Arduino?

Now, I going to explain what I want to do:
-Take a picture and save it in the SD of the 3G module.
-Get the picture of the SD and send it through the Ethernet shield.

vellamy · **Joined:** Mon Jun 04, 2012 12:02 pm **Posts:** 18

I have only had success with the AT+CTX FILE and A+CRX FILE commands between the modem and the Hyperterminal. I don't understand how configure the Xmodem protocol.

Could you up an example please?

libelium-dev · **Joined:** Mon Sep 28, 2009 11:06 am **Posts:** 2057

Hello vellamy:

We don't have any example about the Xmodem protocol. Here you have two links about the Xmodem protocol.
http://mcu.sunplusmcu.com/soft/75_en_Ap ... n_V1.3.pdf
Here you have another link, but this is more hard to read:
http://www.textfiles.com/programming/ymodem.txt

We hope that this can help you.

Regards

vellamy · **Joined:** Mon Jun 04, 2012 12:02 pm **Posts:** 18

Do you think that it is possible to get a file of the 3G module and process it with Arduino Uno?
For example, get a file of SD memory and obtain some bytes of the image with Arduino.

libelium-dev · **Joined:** Mon Sep 28, 2009 11:06 am **Posts:** 2057

Hello vellamy

Thanks for your question.

In my opinion Arduino doesn't have enough power processing to be able to process an image but this depends on what do you want to do with the image, the size of it and the time that you have to process it.

You could search in the net if someone have use Arduino to process images.

Regards.

jimjiminyjimjim · **Joined:** Fri Jan 20, 2012 9:52 am **Posts:** 22

I started a similar thread about processing data stored on the sd card after an http or FTP request.

I think the XModem protocol is very confusing to learn about and have followed the two links but am still none the wiser. There is not much helpful Xmodem and arduino examples.

The AT command instructions show how to recieve a file through hyper terminal but nothing about processing it directly on the arduino

I don't need anything large - just processing stored text files that have been saved to SD.

Is it possible to get some help on the arduino code needed to process the info from an AT-CTXFILE command?

Much appreciated

Jim

djo54150 · **Joined:** Mon Apr 23, 2012 1:45 pm **Posts:** 34

libelium-dev · **Joined:** Mon Sep 28, 2009 11:06 am **Posts:** 2057

Hello jimjiminyjimjim:

You need receive the file (or at least the part that you need) for processing the data. Also, you can use AT+CFTPGET command to get a file from an FTP. With AT+CFTPGET the file from the FTP outputs to serial port directly. See the AT command manual for more info.

Regards