Image transfer demo

[Blaugranas23]

Hi guys! I have had an issue with Image Transfer Demo project. I use nRF52832 with OV2640 camera. I used installation project process described on the page https://github.com/NordicPlayground/nrf52-ble-image-transfer-demo#softdevice-version. The project was successfully compiled an launched on Nordic. Then i downloaded application for Android "ImageTransferDemo". Connection between Android app and the nRF is successfully established and when i try "Take Picture" from the app transmission of Packets normally executes, but picture doesn't appear into app after receiving packets. What the reason could be? Thanks...

[ovrebekk]

Hi 

What model of phone are you using?

Are you able to take a screenshot of the app after the transfer has stopped?

Best regards
Torbjørn

[Blaugranas23]

Hello! Yes, sure! I use "ASUS ZENFONE 5 ze620kl"

[ovrebekk]

Hi

Do you have any other phones you can test with to see if the issue is the same?

Also, do you have a link to the camera module you have?
There are a couple of different version on the market, and they might behave slightly differently. 

Best regards
Torbjørn

[Blaugranas23]

Good morning!

Yes, we have checked the application with different phones, particularly with Samsung note 8.

Link to camera we used https://www.amazon.com/Arducam-Module-Megapixels-Arduino-Mega2560/dp/B012UXNDOY.

Thanks,

Best regards!

[ovrebekk]

Hi

Can you try to comment out line 796 of main.c and see if it works better?
https://github.com/NordicPlayground/nrf52-ble-image-transfer-demo/blob/master/main.c#L796

On some variants of the sensor this line is not needed, and having it in will cause problems. 

Best regards
Torbjørn

[Blaugranas23]

Hi!

Yes, i tried commented out the line "arducam_mini_2mp_fillBuffer(img_data_buffer, 1);", but during transfer i got new issue, it seems application receives not enough bytes of image. Screenshot is attached

Thanks!

[ovrebekk]

Hi 

Then it is hard to say what the problem might be. Can you send me a picture of your board and module?

Did you make sure to pull the latest code from the repo?

The demo hasn't been tested on a Samsung Galaxy Note 8 specifically, but it works nicely on the Galaxy S8 and the Galaxy S8+. I have also tested it on various Nexus phones and a Huawei P20 Pro without any issues. 

For the next week I will be out in Easter vacation unfortunately, but I will follow up the issue again when I'm back in office on the 23rd of April. 

Best regards
Torbjørn

[Blaugranas23]

Hi!

Thanks for your response! Yes, i have just checked again my SDK verison (it is 15.2.0) and i cloned repository for image transfer project by next link "">github.com/.../nrf52-ble-image-transfer-demo.git",  the the master branch is updated.

I'm sending you photos with board and module:

Have a good vacation time,

Best regards!

[ovrebekk]

Hi

Your board and connections look good, that shouldn't be the problem. 

I will order some of the modules and do some testing on my own, but unless I can reproduce the problem it is hard to find the solution. 

Do you have some kind of Bluetooth sniffer so you can take a trace of the communications?

Best regards
Torbjørn

[Blaugranas23]

Hi!

Thanks a lot, i'll be looking forward to your testing results.

Yes, i have a BLE sniffer  PCA10031 dongle, i'll try to set up it on my PC and find out what particular data is sent in packets.

Best regards!

[ovrebekk]

Hi

It will take some time unfortunately, as it takes a while to get the modules shipped to Norway ;)

Once you have some sniffer results please share them, it should be helpful in debugging the issue. 

Best regards
Torbjørn

[Blaugranas23]

Good day! I have caught some packets by sniffer during image transfer, it seems actata are transferred from peripheral device: Sequence of Empty Data PDU packets is sent constantly, and after "Take Picture" action only one ATT packet "Rcvd Exchange MTU Response" is displayed on WireShark screen. The length of this one seems to be 255 bytes, but in the lowest window we can see just 33. I'm sending you a screenshot of transferring packets during Image Transfer Exchange.