Sending a complete file at once from SD card to Mobile App using NRF52840.

[Samiulhaq]

Hello Nordic Family. I hope this post finds you well. 

I am working on a project where I have connected multiple sensors to the NRF52840. I have collected all the sensor's data and saved it on the SD card as a CSV file. The file size is about 240MB which has 60 Hours of data from all the sensors(client requirements). Now I want to send this complete file at once from the SD card to the Mobile App in the fastest possible way. I have run the below program on my board

/cfs-file/__key/communityserver-discussions-components-files/4/8204.ble_5F00_app_5F00_uart_5F00_fatfs_5F00_send_5F00_sdk_5F00_16.0.0.zip.

but this program reads data one by one byte from the SD card and sends it byte by byte to the mobile app which I don't want. I want to send the whole file at once in the fastest possible way not byte by byte. Any help regarding this will be highly appreciated. 

Best Regards,

Sami 

[Håkon Alseth]

Hi Sami,

 

That looks good in terms of algorithm, but this line:

if (err_code != NRF_ERROR_RESOURCES)

Should be expanded to ensure that you do not lose track in cases where the link is disconnected. You should check similar to what is done in the original ble_app_uart sample:

if ((err_code != NRF_ERROR_INVALID_STATE) &&
    (err_code != NRF_ERROR_RESOURCES) &&
    (err_code != NRF_ERROR_NOT_FOUND))

 

Kind regards,

Håkon

[Samiulhaq]

Hi Hakan sir, Thanks for the suggestion.

Do I just have to add the code snippet you provided? 

Best Regards,

Sami

[Håkon Alseth]

Hi Sami,

 

You should test with the proposed change and see if this works for your use-case.

 

Kind regards,

Håkon