From beginner: MMC access in Code Composer Studio (OMAP-L137)

Rizuan,

According to your title, it appears you want to do this via CCS; is this correct?  FYI, in order to see and access files, you normally have to have a file-system supported (YAFFS, JFFS2...); normally, high-level operating systems such as Linux (available for OMAP-L1) have good support for file-systems.  However, CCS is just an IDE; I believe it includes DSP/BIOS as the operating system for DSP side of OMAP-L137 and can talk to ARM without an OS; however, CCS v3.3 is not Linux-aware.

Therefore, if you are attempting to do this via Linux, the following wiki may help: http://tiexpressdsp.com/index.php/HOWTO_Create_Filesystems_on_DaVinci

If you are trying to do this via CCS, you may need to try our CCS v4 Beta while running Linux on the target: see http://tiexpressdsp.com/index.php/Linux_Aware_Debug for details.

Hi Juan,

Thanks for your reply. How about the maximum size of SD card supported by the OMAP-L137 board?

Thanks.

Best regards,

Rizuan

With BIOSUSB on the DSP side, I got a 4 GByte SDHC working. 

On the ARM side with Linux, I only got 2 Gbyte SD working.  But I think there is a patch available for Linux to get SDHC.

I'm not sure if the patch is for OMAP-L137, the driver as is does not support SDHC.

Some customers have implemented for DM365:

https://community.ti.com/forums/t/6206.aspx

So you could take this as an example.

Guys,

Thank you for your response. I'm still in the beginning of my project. I'm quite worried since Linux itself is still a new area for me. But I believe I can get a good support from TI Support Team. And I believe, although the information in this thread is very basic, there are many peoples out there that looking for this kind of information for starting up using OMAP.

Thank you.

Best regards,

Rizuan

Rizuan,

You can access MMC/SD card on OMAPL137 platform through CCS using the PSP BIOS drivers (BLKMedia and MMC/SD driver) on the DSP side. Also RTFS file sysem support is also available for this platform.

Here is the location to download PSP drivers. You need to to my.ti login download the packages.

https://www-a.ti.com/downloads/sds_support/targetcontent/psp/bios_psp/index.html

Regards,

Nag

Thanks Nag,

Surely I will try this first. You help is much appreciated.

Regards,

Rizuan

Hello，Friend：

I am chinese,and now I am debugging the OMAP-L137 EVM board.

I am a beginner,and have some questions to ask you.

Thank you for reading this letter,and hope make friends with you.

Waitting for your reply,thank you very much.

 Best regards for you.

Chen Yong.

My QQ number.  254421570

Hi,

I will try my best to answer. This is the purpose of the forum. For your information, I have tried to run the example about reading and writing files from/to MMC card on OMAPL-137 successfully. However, I don't have chances to explore more (built my own program to do that) since currently I'm working on another part of my project. If you want to know how to set up all the PSP driver, RTFL etc., I'm willing to help.

Regards,

Rizuan

Hi,Rizuan,

First,thank you very much for replying the letter.

I want to ask how can I communicate with the ARM Kernel on OMAP-L137,for example ,how can I use the ARM Kernel to light a LED on the OMAP-L137 Board.And can you give me some code examples or projects about the OMAP-L137 Board?

Can you give me your  EMAIL or your MSN number,for this may make me more convenient to communicate with you.My EMAIL:cyong1986@126.com

Thank you very much.

Best regards.

Chen Yong.

Hello everybody,

I've tried to read a small binary file from the SD card by using RTFS in CCS. My actual task is to read a large file (more than 100 MByte), but the amount of SDRAM available on the board (OMAP-L137) is just 64 MBytes. Can we store any variable in the SD card ? how can we use the #pragma DATA_ALIGN to do that ?

Best regards,

Rizuan

Hi,

In order to be able to store an specific variable or use DATA_ALIGN  the space you need would have to be memory mapped.

For the SD card case, I do not think it is possible to to have the access memory mapped like when using EMIF interface. So what you would probably need to do is, if you are using the RTFS, is to put the data you need in a file and read the file using the functions from RTFS.

Hi Mariana,

Thanks for your reply. I'm thinking the same method as yours.

Best regards,

Rizuan

Hi,

I'm referring to DSP/BIOS Real-Time File System (RTFS) 1.10 API Reference Guide (SPRUGM0A). I've tried both of fopen-fread and open-read to read a binary file which contained 1x262144 Uint16 variable, and there will be less than 60 files to read. The binary files are actually images that I need to read from the MMC/SD to process.

I found that using fopen-fread is slower however the open-read only read in 8-bit chunks (char). Does anyone have suggestion ? I've tried to combined 2 8-bit chunk to get 16 bit data however this is extremely slow.

Thanks in advance

Rizuan