NUS central and DFU using Serialization

[TS Gowtham]

Hi,

I'm using 2 nRF52832s in my project. One of them is connected to a PC serially and has NUS central running on it and the other nRF52 connects to this central. I was able to get the HRM example running with the connectivity firmware on the nRF52 which is connected serially to the PC.

1. Similar to the Serialized HRM example, are there any examples of NUS central which I can use with the HCI BLE connectivity firmware?

2. I would also like to use the nRF52 which will be running the connectivity firmware as an intermediary to perform a DFU on the peripheral nRF52. Is this possible?

Thanks

[TS Gowtham]

Hi,

Your last answer helped me quite a lot, thanks for that.

I was able to reach till the characteristic descriptor discovery part, but I'm facing the following issues:

1) I followed this link's suggestion and incremented the handle by 1 and called the characteristic discover function. But I noticed that the characteristic handles are being allotted in increments of 2.

        NUS RX Characteristic handle = 0x000C

        NUS TX Characteristic handle = 0x000E

But the above link says to increment by 1 and the graph in the link just states a variable N. So is this value programmer dependent?

2) When calling the descriptor discovery function, I'm getting the following CCCD details:

       Handle = 0x000E

       UUID = 0x2803

Is the handle supposed to be same as that of the TX characteristic's handle? Also, from what I understood the CCCD UUID should always be 0x2902. If yes, then any specific reason why I am getting a wrong UUID?

[Vidar Berg]

Hi,

0x2803 is the characteristic declaration so  seems that the value handle for the NUS TX Characteristic handle should be 0xE + 1. Recommend to have a look at this blog post for a better explanation of the attribute table layout: https://devzone.nordicsemi.com/tutorials/b/bluetooth-low-energy/posts/ble-characteristics-a-beginners-tutorial. 

I have not verified it, but it looks like you can use the existing discovery functions used in heart rate collector example and just change the UUIDs to filter on, or is that what you have done already?