nRF52833-DK blinky problem

[Marry]

Hello! I have the following issue with my nRF52833 board: I am in the first stage of working with it and I wanted to try the simple blinky example.

However, since there is no pca10100 hex file in the examples/peripheral/blinky/hex folder, I decided to load pca10040. Now, my board seems to be irresponsive, i.e. LED1 doesn't blink when the board is powered on. My questions are:

1. Is there any possibility to reset the board (so that I start again from scratch with my test)?

2. I suppose I didn't damage some internal circuit by loading the pca10040, but I'm not completely sure - since I don't know exactly what it does. Could you please explain me?

3. Is there any hex file for the nRF52833 board with pca10100? (although I still don't know what is the difference between all versions).

Thank you in advance!

[Jay Tyzzer]

Hi Marry,

The reason the pca10040 (nRF52832 based) Blinky example did not blink the LEDs is because the GPIOs assigned to the 4 LEDs are different.  If you want, you can try the example for the PCA10056 (nRF52840) board , attached. I just tried it and it is working fine for me.  The LEDs are mapped out the same. So if you load in the HRS example you will see LED 1 blink while it is advertising and go solid when it is connected.  You can download the nRFConnect for Mobile or nRFToolbox for your IOS or android and use it as the central. 

The nRF52833 is a subset of the nRF52840.  Less memory, some GPIO changes / reassignments, etc.  I have included a comparison chart for your to reference.   Nordic is planning on releasing a new SDK this month.  I believe that the nRF52833 will be included. 

nRF52833_nRF52840_Comparison version 2.0.0.pdf 6433.blinky_pca10056.hex

Good Luck!

Br,

JayT

[Marry]

Hello Jay,

And thank you for your quick answer and for the attachments - really useful!!

I tried the hex file which you provided me and it works, although it's not only LED1 that blinks, but all 4 of them have an interesting behaviour (I attached a short video with the board). I have some more questions now

1. Is there any way that I see the code of the hex file? I'm new and I'm trying to understand how this board and code works and afterwards try something on my own.

2. So now, I want to get to know my nRF52840 board and run some pre-defined examples.

But from my understanding, there are no pre-defined examples already done for this board, right? (but they will appear soon). If this is the case, I also consider buying another board, for which more documentation already exists and has many bugs fixed. For instance nRF52840 board can be an option - so that I can have at least a starting point with something that works already. :)

Thank you again.

Best regards,

Marry

[Marry]

Marry said:

know my nRF52840 board

* Correction: my nRF52833 board

[Karl Ylvisaker]

Hello Marry,

Marry said:

I tried the hex file which you provided me and it works, although it's not only LED1 that blinks, but all 4 of them have an interesting behaviour (I attached a short video with the board). I have some more questions now

This is the intended behavior of the blinky example, the "LED 1 blink while advertising" comment was made with regards to the Heart Rate Monitor(HRS) example.

Marry said:

1. Is there any way that I see the code of the hex file? I'm new and I'm trying to understand how this board and code works and afterwards try something on my own.

Unfortunately it is infeasible to go from the .hex file back to the original code, but if I am reading Jay's reply right he has not made any modifications to the SDK code for the .hex file he supplied - which means that you may see the code that generated the .hex in the SDK folder under /examples/peripheral/blinky.
Are you using the Segger Embedded Studio IDE? If so, you can find the segger project under /examples/peripheral/blinky/pca10056/blank/ses.

Marry said:

2. So now, I want to get to know my nRF52840 board and run some pre-defined examples.

Marry said:

But from my understanding, there are no pre-defined examples already done for this board, right? (but they will appear soon). If this is the case, I also consider buying another board, for which more documentation already exists and has many bugs fixed. For instance nRF52840 board can be an option - so that I can have at least a starting point with something that works already. :)

There is a number of examples available for the PCA10100 in the new SDK v.17(released last Friday), but it is somewhat more limited than what is available for the nRF52832 and nRF52840.
Running PCA10056 .hex files on the PCA10100 works because blinky is such a simple example - just toggling the LEDs - but it will not work with the larger examples, since the PCA10056 has a nRF52840 SoC which has a bigger flash memory and ram. I can therefore not guarantee that it will work with all the examples, but as long as the nRF52833 has the peripherals used by the example and the example is within the size constraints it should work(at most maybe some GPIOs must be reconfigured).
I gave this a try with the BLE peripheral Heart rate monitor(HRS) example, loading the nRF52833 DK with the s140_pca10056 and it seems to work as intended right off the bat.
If you look into the HRS peripheral source code, familiarizing with it might seem a daunting task at first - but know that much of it is BLE connectivity configuration that you may reuse in your personal projects.

If you are looking to familiarize yourself with the BLE development process, I highly recommend looking into the BLE advertising, BLE custom service and characteristic tutorials.
The tutorial is unfortunately not updated for the PCA10100, but there exists a version for PCA10056 with S140.

Please do not hesitate to let us know if you should encounter any other questions or issues!

Best regards,
Karl

[Marry]

Hello Karl!

Your answer is indeed helpful, thank you so much! Yes, I am using SES. And now it is more clear to me that why the examples from the 52840 SoC are not running on my 52833.

So, what do these PCA and SoftDevice contain? I suppose they are related to the SoC, since they differ between 52840 and 52833, but I am curious why 

Karl Ylvisaker said:

SDK v.17(released last Friday)

I did not know about this - so thanks!

Karl Ylvisaker said:

Running PCA10056 .hex files on the PCA10100 works because blinky is such a simple example - just toggling the LEDs - but it will not work with the larger examples, since the PCA10056 has a nRF52840 SoC which has a bigger flash memory and ram.

OK, I understand, thanks a lot! Considering this, the best option for me is to just buy a development board which has the 53840 SoC, in order to run the predefined examples. Actually, the reason I chose this 53833 SoC was because it was advertised for its bluetooth low energy feature (but on a closer look, 53840 seems to have this too).

Karl Ylvisaker said:

f you are looking to familiarize yourself with the BLE development process, I highly recommend looking into the BLE advertising, BLE custom service and characteristic tutorials.

That is extremly helpful, thank you very much!

I will come back in a new post, as soon as I advance and I have new questions, thanks!

Best wishes,

Marry