Mbed OS not work on nRF52840-DK

[UriC]

I received  nRF52840-DK from Mouser :

Sales Order No: Web Order No: Order Date:

242789421 14270760 29-May-18

I started to use it and some problems exist:

 

1. I placed power selector to "USB" and connected USB cable but board is not powered.

It's work only when I select "external power source" and  connected USB cable. I don't know what need select when I connect  "external power source" or "lithium battery"

 

2. I got it for use with Mbed OS.  I used online compiler with simplest "mbed-os-example-blinky"

After success compilation I placed bin file to JLINK drive but after reboot led is not blinked :(

I opened settings of board : https://os.mbed.com/platforms/Nordic-nRF52-DK/

and see that it's not same board I received.

Please help to make it work.

[UriC]

Please add nRF52840_DK to boards os.mbed.com/.../

[Edvin]

Hello,

mbed is not driven by Nordic, so you have to ask mbed to add the nRF52840_DK to https://os.mbed.com/platforms/ 

 

As for the first question:

Which usb port on the DK do you use?

You should use the one on the left in the upper picture in this link.

The switches should be in position VDD and DEFAULT.

So if you want to program the nRF52840 DK, you should use the USB connector with the red circle around, SW9 - nRF power source: VDD and SW6: DEFAULT.

 

I am not familiar with mbed, but if the nRF52840 is not yet supported there, you can check out our SDK, which contains a lot of examples you can play around with. Segger Embedded Studio (Segger's IDE platform) is also supported, which is free of charge to use, with no limitations.

 

Best regards,

Edvin

[Edvin]

Hello,

I was not able to follow your link. It opens my compiler environment, but not with the project that you are linking to.

Sorry. I am not very familiar with mbed. But I found an example called mbed-os-example-blinky. I suspect it is the same as you use. I found it here.

I compiled it, and downloaded the .hex file. I tried to drag'n'drop it, but with no luck. All the LEDs remained on. 

Then I used nrfjprog or nRFgo Studio, and erased the board, and programmed the .hex file via that. Then I reset the board, and it worked. Can you try to use either nRFgo Studio or nrfjprog (command line tools) with the project that I linked to? (which hopefully is the same project that you linked to.)

 

Best regards,

Edvin

[UriC]

1.I used introduction link :https://os.mbed.com/docs/v5.9/tutorials/quick-start-online.html

2.  I don't have this Studio and not CL tools.I want to use high-level programming language with less code as possible. for this kind users was created Mbed and I wan't to use it. So please make it work/

[Edvin]

I am just trying to figure out whether your issue is in the project/compiler or if it is in the upload procedure.

Can you try to power cycle the DK after uploading the .hex file using drag'n'drop?

nRFgo Studio is a quite easy-to-use, and self explaining application. 

 

Best regards,

Edvin

[UriC]

I told it many times that I know it and it work. Examples I tried with SEGGER Embedded Studio worked.

Problem in code that generated by online compiler. Nordic + ARMbed need to solve this problem. 

[Edvin]

I guess that the nRF52840 platform is not working yet. If you compile the project that you linked with this main.cpp:

#include "mbed.h"

DigitalOut led1(P0_13); //LED1 = 13 on nRF52840 DK

// main() runs in its own thread in the OS
int main() {
    while (true) {
        led1 = !led1;
        wait(0.5);
    }
}

And use the nRF52DK as platform, it works.

After uploading the binary, you have to power cycle the board(!) not just the reset button.

 

I know that this is not ideal. But I have no better solution, until a stable version of the nRF52840 platform is released on mbed.

 

Best regards,

Edvin

[UriC]

If you look at start of discuss I started with nRF52DK as platform and always power cycle the board.

ARMbed found bug in last version of mbed 5.9.2 When I swapped to 5.9.1 led is worked.