BLE UART/SPI

RE: BLE UART/SPI

agus.uy — Fri, 05 Oct 2018 15:42:24 GMT

thank you!!

I'll probably be back asking about bonding and security, and certification, but on a new post.

RE: BLE UART/SPI

awneil — Fri, 05 Oct 2018 15:35:54 GMT

It's the post of 1 Oct at 17:05 -

[quote userid="6462" url="~/f/nordic-q-a/39029/ble-uart-spi/151049"]The SoftDevice is the BLE Stack - the code you write can do the comms with the rest of your system.[/quote]

RE: BLE UART/SPI

agus.uy — Fri, 05 Oct 2018 15:27:29 GMT

I get the idea, to add a layer between the MCU and nRF exposing what I need. I'll work on it.

The link takes me to this same post...

RE: BLE UART/SPI

awneil — Fri, 05 Oct 2018 15:13:53 GMT

Yes - you write yourself some sort of UART-based API.

AT Commands is a common example (as initially mentioned) - but you can make up your own protocol to suit your specific needs ...

EDIT

See: https://devzone.nordicsemi.com/f/nordic-q-a/39029/ble-uart-spi/151049#151049

(the way this forum shuffles posts makes it hard to find specific replies - took me a while to find that!)

RE: BLE UART/SPI

agus.uy — Fri, 05 Oct 2018 15:08:57 GMT

OK,

I'm starting from the UART, I'll just change how to connect (security, power)

Is there a way to have some control of the BLE from the application MCU? Because if I understand correctly I have only the UART that goes through.

RE: BLE UART/SPI

haakonsh — Wed, 03 Oct 2018 11:01:14 GMT

The UART/Serial Port Emulation over BLE example is definitely the way to go in your case. I would forget the serialization library as it is not suited for your use-case.

Once you have the UART over BLE communication up and running you can offload other tasks from the main MCU if you want to.

RE: BLE UART/SPI

agus.uy — Tue, 02 Oct 2018 15:45:22 GMT

My BLE needs are very low power and security. It will not advertise unless instructed and ideally it will be completely silent except during communication.

The device needs to receive configuration and answer to commands from a PC/Tablet or phone, this just a few times a day. Data is just plain data, so the Nordic UART over BLE is a good fit to start with.

A version of the application is already running with a BT 2 module, using serial cable emulation, with no security and high power, with AT style control.

I'd like to substitute the module with a nRF. Initially I want to use it as is, if possible not writing code for it (using an existing FW from nordic) and controlling BLE through SPI or UART. I don't mind porting some libraries to do this, but it would certainly help if they are already made.

After this solution is working the next step will be shifting the comms processing entirely to the nRF, but that will be a separate effort. I don't think I'll be able to move all my application to the nRF due to timing, I/O and peripheral requirements.

RE: BLE UART/SPI

awneil — Tue, 02 Oct 2018 14:50:59 GMT

I think I agree. (though still not entirely clear)

Rather that try to do this hybrid half-way-house mash-up, I think it may be easier to just treat this as a new development.

ie, start on nRF with some basic BLE functionality, and bring in stuff from your "main" app ...

RE: BLE UART/SPI

haakonsh — Tue, 02 Oct 2018 14:45:20 GMT

Well, since your end goal is to keep the BLE application on the nRF52 I think you should consider not to use serialization as you will save a lot of development time in the long run. To use the serialization library you need to port a lot of our drivers and libraries to your host MCU.

What exactly are your BLE needs?

RE: BLE UART/SPI

agus.uy — Tue, 02 Oct 2018 13:48:10 GMT

Hello,

I'm first trying to have a solution with an application MCU with all my code, and a nRF for BLE connectivity with a FW I don't have to change (ideally just flash a code from nordic). After that is working I can advance other parts of the design both HW and application FW.

I'll eventually start moving code to the nRF but not now.

RE: BLE UART/SPI

haakonsh — Tue, 02 Oct 2018 11:24:06 GMT

"But it remains unclear to me what the OP is actually trying to achieve."

Yeah we need some more information :)

RE: BLE UART/SPI

awneil — Tue, 02 Oct 2018 10:00:12 GMT

Indeed.

But the OP talks about moving stuff to the nRF from the host - and Serialisation seems to me to be the opposite of that?!

But it remains unclear to me what the OP is actually trying to achieve.

RE: BLE UART/SPI

haakonsh — Tue, 02 Oct 2018 08:31:56 GMT

Well it depends how much of the BLE application you want to run on the host processor.

You can offload all of your BLE application on the nRF52, but you will have less control from the host processor.

With the serialization library you will not have to flash the nRF52 whenever you want to change your BLE application as in runs solely on the host processor.

RE: BLE UART/SPI

awneil — Tue, 02 Oct 2018 07:52:10 GMT

No, I don't think "Serialisation" is what you're looking for:

"Serialisation" is about having the Nordic code running on your host processor - which sounds like the opposite of what you're saying?

RE: BLE UART/SPI

haakonsh — Tue, 02 Oct 2018 07:46:27 GMT

We've got an example in nRF5_SDK_15.2\examples\connectivity\ble_connectivity :)

RE: BLE UART/SPI

agus.uy — Mon, 01 Oct 2018 17:14:59 GMT

What I'm looking for is an example that does that.

Serialization seems to be a solution. Do you know if there's an example I can start with?

RE: BLE UART/SPI

awneil — Mon, 01 Oct 2018 17:05:52 GMT

Yes, you can certainly do that.

The SoftDevice is the BLE Stack - the code you write can do the comms with the rest of your system.

RE: BLE UART/SPI

agus.uy — Mon, 01 Oct 2018 16:56:53 GMT

Basically, yes. Not necessarily AT commands, but yes.

After having a working hardware I'll start moving code to the nRF52

RE: BLE UART/SPI

awneil — Mon, 01 Oct 2018 16:12:44 GMT

You mean, you want the nRF52 to act like a BLE "modem" - controlled by AT commands?

RE: BLE UART/SPI

agus.uy — Mon, 01 Oct 2018 15:03:06 GMT

It's a complex device with many I/O and strict timing (to micro seconds). We use several concurrent timers, DMA, ADCs and DACs.

We use BT with an older module controlled with AT commands, and we want to upgrade to BLE with a nordic chip (or module).

The first step will be substituting the module, then we'll evaluate migrating the code to the nordic (or some or it).

The serialization looks good, is there an example for both the application and connectivity micros?

RE: BLE UART/SPI

haakonsh — Mon, 01 Oct 2018 13:50:36 GMT

"Does anyone know if there is a FW I can use that will allow using the nRF52 as a similar module through SPI or UART? Or is the nRF52 a bad choice here?"

Well we've got the Serialization library, but the nRF52 is quite capable as a SoC on its own. Do you really need another MCU? What exactly are your needs?