STM32N6570-DK | VENC_SDCard_ThreadX | Using exFAT

[dksmith]

I have been modifying the VENC_SDCard_ThreadX example to read in raw data through pipe0 with success. However, my bottleneck appears to be the SD card write speed; I understand that this example was designed to write compressed h.264 files - and it looks like it only writes at around 320 kB/s.

Since I am capturing much more data, I would like to use exFAT instead of FAT32, and write to a UHS I card at max speed (SDR104). I defined FX_ENABLE_EXFAT within fx_user.h, but it I am still unable to write to an exFAT formatted card.

fx_media_open() passes just fine, but upon inspection it appears that the available clusters always is 0. Am I missing any steps? Any insight would be appreciated.

[Saket_Om]

Hello @dksmith 

Could you share your code please, then we can assist you more effectively. 

[Will_Robertson]

Hi @Saket_Om and @dksmith 

Thank you very much for this discussion.

We're looking at using STM32N6x7 to receive video from ST image sensors via MIPI CSI-2, do h.264 encode and write it to a FAT32 or exFAT filesystem on SD for a new open source wildlife camera for conservation of endangered dormouse species.

It would be great to know if you were successful in adapting this example to write to exFAT?

Thank you very much!

Will

[dksmith]

Hello,

To test writing to exFAT I have just been running the unmodified VENC_SDCard_ThreadX example code. I made sure FX_ENABLE_EXFAT was defined in fx_user.h. This was my only edit. 

[dksmith]

I have also attempted to use fx_media_exFAT_format() to format the card for exFAT upon initialization, but no change. It seems like the cluster size always starts at 1 and then becomes zero.