OTA DFU speed

[Sergy]

Hi,

We are using OTA update in production and currently it takes about 40 seconds to update 70KB image. Is there a way to improve the speed?

Thanks!

[Vidar Berg]

Assuming master control panel version 3.10.0 you can do the following changes to the DFU script to increase overall throughput:

Step 1. Reduce connection interval:

Open "\Master Control Panel\3.10.0.14\lib\dfu\master_emulator.py", go to line ~237 and replace the following code snippet:

        conn_params.ConnectionIntervalMs = 15
        if self.master.Connect(self.myPeerDevice.DeviceAddress):

with

        conn_params.ConnectionIntervalMs = 11.25
        if self.master.Connect(self.myPeerDevice.DeviceAddress,conn_params):

Step 2. Disable packet receipt notification:

Open "\Master Control Panel\3.10.0.14\lib\nordicsemi\dfu\dfu_transport_ble.py", go to line ~109 and change the packet number from '10' to '0'.

If I remember correctly this should take about 10-15 seconds to upload the image with the above changes.

[Vidar Berg]

Is it possible that it's not invoking the correct dfu_transport_ble.py script? Sounds like the change you did is not being applied.

Can you share the command line arguments so I can try the same here?