Possiblility of working as bridge between BLE client and PC

[OldXiao]

I have browsing this site, no clearly answer found, but,I think someone has done this job before.

My scenario:

.many BLE client (5.0 above);

.BLE clinet will upload data to server if data created,the volumn is low,and the frequency is low too,you can image a sensor;

.In long range mode(though the actual range is limited)

I have developed the server app on PC, but we all know the concurrent connected BLE is limited on PC too.

So I want to build a bridge/gateway between BLE clients & server(PC or any powerful hardware).

20 concurrent connections is the limit for Nordic series under nRF5 SDK.I think this amount is acceptable for me, I can adopt many bridge to extend connections.

I am sure nRF52840 can work, but how about nRF52820? there is no so much workload for the bridge, and nRF52820 has USB,and it is cheaper of course.

By the way,I am newbie on BLE and Nordic series, give me a advice on example to start.

Thank you.

[Edvin]

Hello,

You say that you have developed an application for PC, but you need to be able to connect to more devices than what you currently are, is that correct? So you are using the PC's BLE chipset at this point in time?

Do you want the nRF52840 to work as a generic BLE dongle for your computer? In that case, it will not work with windows, because it doesn't support Bluetooth Classic (mostly used for Bluetooth Audio), and windows require all bluetooth dongles to support Bluetooth Classic. On Linux, it can work, because it doesn't have the same requirement. 

But if you are thinking about some device connected to your computer via serial/USB, handling the application, and just communicating with your computer using serial communication in an application specific protocol, then that is possible.

I cannot guarantee that you will be able to maintain 20 connections, as that has a lot of dependencies. It depends on how many Services and characteristics your peripherals have, which will put a strain on the nRF52's memory consumption.

It also depends on your connection parameters. It takes some time to handle a connection every connection interval, and if you have too many connections with a short connection interval, then there will not be enough time to handle all of them.

So I would say that you will have to experiment with a central application,  running on the nRF52 device that you end up with* , and see if it is possible to do what you want to acheive. 

* I suggest you start with the nRF52840 DK as your central device. If it works, you can try to build it for the nRF52820, and if the memory allows it you will be able to simulate the application running on an nRF52820 on your nRF52840 DK. Then you can decide what device you want to use before going into production.

Best regards,

Edvin 

[OldXiao]

Very nice explanation,thank you.

The topology is : BLE client <-> bridge based on nRF52 <-USB-> PC.

32K RAM is a bit less,that is why I raise this post.

I have ordered 2 52840 USB dongles,will try to validate my ideas.

But have to learn SDK first,I have quit while learning DA14531,hope I will not quit again.

I will post info later if I don't quit. 

[Edvin]

Best of luck! If you want to speed up the learning process of the SDK, I can really recommend that you get hold of an nRF52840 DK, as these have an onboard debugger, so it is a lot easier to do development on those. When you are done, you can port your application over to the nRF52840 Dongle.

Another tips is that you can look into the Nordic Developer Academy, which has a few courses that are good if you are just getting started with our SDK. They are listed here:
https://academy.nordicsemi.com/

I suggest you start with the nRF Connect SDK Fundamentals course, as it gives you an intro in how the SDK works.

Best regards,

Edvin

[OldXiao]

Thank you very much.

I begin to customize BLE_Center_multi example to suit my requirements.

BLE function OK(20 BLE instance)

USB function OK

So,I'm sure I can build the gateway based on PCA10059.

A lot of learning & porting work ahead,of course.

Close this ticket pls.