nrf52840: Serialization

[CheMax]

Hello. Nordic team.

Once again I had questions, this time related to serialization. 

While the preparation of the driver is on the PC side, I am studying the examples described in the documentation. At the moment, I have the following questions:

1. In the examples, I did not find mention of updating the firmware of the "Connectivity" chip. Can I use the standard bootloader to upgrade?
2. Adding custom events and commands is possible? How to do it correctly (an example will suffice)?
3. There is no example "BLE Heart Rate Collector Example" for the board pca10056. Since the kit pca10040 is not at hand, is it possible to change the project for working with pca10056 or is there an example already fixed?
4. Do you need preliminary configuration of the project for the connectivity chip (MTU, DLE, max connection count)? Or can all this be configured in the application code?
5. Replacing the transport level with USB CDC is possible, as I understand it. Based on what example can a transport level be replaced with USB CDC. Are there any restrictions?

While waiting for an answer, I will continue independent research on this issue. Perhaps the list will be supplemented (or shortened if I find an answer earlier )

Best regards,

Chelobitchikov Maxim

[Hung Bui]

Hi CheMax, 

I have checked with the development team. The answer is that the connectivity firmware in the SDK is not drop-in compatible with the pc_ble_driver. And you can't use the example in the SDK with the pc_ble_driver. So only the .hex provided in the pc_ble_driver should be used. 
We currently don't have a plan to providing support for api v7. 

So the only solution if you want to use API v7 is to write your own application on PC side to control the connectivity firmware from SDK v16. 

But i don't really understand if you are plugging the dongle into PC why would power consumption be an issue ? 

[CheMax]

Hi Hung,

The dongle will not only connect to the PC, but in some cases will be part of the device, the so-called "signals hub". This device may have battery power.

The issue of consumption arose due to the introduction of time synchronization based on time slots. To reduce energy consumption, it was decided to run slots before connection interval started (I described a little more in a new question regarding time slots here

Hung Bui said:

The answer is that the connectivity firmware in the SDK is not drop-in compatible with the pc_ble_driver. And you can't use the example in the SDK with the pc_ble_driver.

). But the event of the beginning of the connection interval is available only in the 7th version of the stack ...

That is, the need to switch to the new version is due not so much to consumption as to new available functionality ...

Hung Bui said:

The answer is that the connectivity firmware in the SDK is not drop-in compatible with the pc_ble_driver. And you can't use the example in the SDK with the pc_ble_driver. So only the .hex provided in the pc_ble_driver should be used.

Ummm, I didn’t understand a bit.
Does a hex-file mean a softdevice file? If so, then why is there no file here?

Hung Bui said:

So the only solution if you want to use API v7 is to write your own application on PC side to control the connectivity firmware from SDK v16.

If you look here, it turns out that the serializer is taken directly from the SDK. This follows from the description:

Content
This directory contains the common codecs for SoftDevice API version 3 to SoftDevice API version 6. The codecs are updated at regular intervals from the latest versions of the nRF5 SDK.

The SDKs are found here: https://developer.nordicsemi.com/nRF5_SDK/

So the task of the driver is only to provide support for the transport of commands / events between the stack and the application? Then, theoretically, replacing the SDK files with new ones, the driver file will continue to work. It remains only to add the required functionality at the application level?

Also, time control over time intervals will be fully implemented in the connectivity chip.

[Hung Bui]

Hi CheMax, 

The hex file of the connectivity firmware is provided inside the release .zip file you can download here: https://github.com/NordicSemiconductor/pc-ble-driver/releases

But it's true that the connectivity firmware is actually built from the \examples\connectivity example in the SDK, with the patch provided in the repo. 

So it's possible that you can implement the same patch on SDK v16 (You would need to go through to patch to see how it should be implemented in SDK v16). But we haven't tried that and i can't guarantee that it would work 100%. 

[CheMax]

ok, thanks.

In any case, we would need to transfer this code to CT. So, we will do as Master Yoda bequeathed.

I think that at this stage the questions on this topic have ended. Thanks for the help, patience and understanding)