Speedup upload procedure via BLE

[astronomer]

Hi, I'm trying to find a way to speedup the upload procedure of an application, via BLE on a Arduino Primo with the DFU service.

Here you can find my code: https://github.com/astronomer80/ota-dfu-python/blob/master/dfu.py At this time it needs several minutes! I created an application in c# for windows and it takes about 30 seconds to upload an application.

I tried to increase the packet payload size but it doesn't work. The procedure goes to the end but giving the "ACTIVATE_FIRMWARE_AND_RESET" command, gatt replies that the command goes in timeout and the application doesn't start.

At row 134 you can find the parameters that I tried to change:
#TODO Check this parameter to speed up the procedure
pkt_receipt_interval = 10 #DEFAULT=10
pkt_payload_size = 20 #DEFAULT=20

I tried different values for the pkt_payload_size, from 40 to 500. I think that the issue is on the packet receipt notification but I don't understand how to solve.

Here you can find the application that I'm trying to upload: github.com/.../example

and here the DFU I'm using: github.com/.../DFU

[ovrebekk]

Hi

This issue has been discussed in the following case:
devzone.nordicsemi.com/.../

The short of it is that this is caused by only passing one packet at a time to the stack, in the python driver.

Best regards
Torbjørn

[astronomer]

I'm using python with pexpect just as a wrapper of gatttool. nrfutil is used only to create the dat file starting from the hex. I'm sorry, I don't understand where I should work to improve the speed of the upload, considering that on Windows and Mac the uploading is very fast. Thanks

[ovrebekk]

Do you know what the connection interval is during the connection?
If you have a short connection interval the speed should be pretty good, even if you only get 1 packet per connection event.
If you are unable to change that I would recommend using the node.js command line programmer, as instructed in the other case.