Doubts about programming

RE: Doubts about programming

Simonr — Wed, 05 Feb 2020 14:03:08 GMT

Hi Anderson

Glad you got it working! Yes, it should not be a problem to make a HelloWorld example that can be flashed onto your nRF. You can take a look at our blinky example that should be ready to be flashed when downloading our SDK.

However, we try to keep each ticket to its own topic as that makes the forum easier to navigate for people with similar issues in the future, so if you have any further questions on MBED development, I suggest you make a new ticket dedicated to that subject.

Best regards,

Simon

RE: Doubts about programming

Anderson Silva — Wed, 05 Feb 2020 11:21:54 GMT

Hi Simonr.
Thank you so much for your help.
These resistors (R28 and R29) are not mounted. We put them in the circuit just to imagining (preventing) if these would be necessary pull ups... But after manufacture the PCB we confirm that wasn't necessary.
But we realised what was the problem yesterday and fix it. All the PCB had a problem in the conection from some pads (in top layer) and midlayer (intermitente conection). So we manufactor another PCB and it worked very well.
Thank you very much for your help. With you w could filter and aliminate problems till find the real problem.

Now I wish to ask you another question...
Is it possible to create a simple "HelloWorld" code in MBED and program the Nordic with J-LINK?
I'm asking you it because I've created a code to blink a led but it doesn't blink the led.
I've created a new program in MBED using Nordic nRF52-DK with template "(mbed OS 5)Blink LED HelloWorld" as you can see in the images bellow.
And I'm trying to blink the a led connected to pin P0.28 in my PCB. But it doens't works. I've already confirmed that led circuit works.
In the Nordic Dev Kit (nRF52-DK) this program works very well (using the pins P0.17 ~ P0.20)... But in the PCB it doesn't works... So I believe that probably MBED just Works with Dev Kit.
Is it correct?

Thank you very much again.
Anderson

RE: Doubts about programming

Simonr — Tue, 04 Feb 2020 07:43:12 GMT

After looking at your layout, can you tell me whether the resistors R28 and R29 are mounted or not? Why are the SWCLK and SWDIO pins connected to the 3V3 net via these resistors? When programming these pins should only be connected to the SWD pins on the debugger and not have a voltage on them. The external chip must be powered itself, but not the SWD pins.

Best regards,

Simon

RE: Doubts about programming

Anderson Silva — Mon, 03 Feb 2020 12:41:14 GMT

Hi Simonr
These are the Gerber Files.
As you can see I've placed the componentes as close as possible from the respective pins. But I've placed in the othe PCB face...
But I didn't imagined that it could cause the problem with programming process....
Actually I'm still not so sure if this is the problemm...
I believe that it could cause problems with performance or something related with Bluetooth... But not with programming process...
Thanks for your help.
devzone.nordicsemi.com/.../PCB_5F00_Nordic.zip

RE: Doubts about programming

Simonr — Mon, 03 Feb 2020 06:57:19 GMT

Hi Anderson

As long as the components still are as close as possible to the board pins moving them to the other side of the board shouldn't be detrimental for your design. Do you mind uploading the Gerber files of your design so I can confirm whether or not your design is the problem?

Best regards,

Simon

RE: Doubts about programming

Anderson Silva — Fri, 31 Jan 2020 15:44:12 GMT

No no....
The electrical connections are OK. The componentes are placed in correct positions.
But the datasheet recomends to put the nRF in the TOP face and the periferal componentes in the TOP too (as close as possible of respecitive pins).
But I've done the layout with this periferal devices in the BOTTON face.... and the nRF are in the TOP face... So the electrical connections are right. There's no electrical mistakes... All the connections cross the PCB (by vias) from nRF (in the top) to perifecical devices (in the botoon)...
I just haven't followed the recommended layout.
But I'm not sure if it would cause the problem with programming procedure...
Do you think that it could be the reason?

RE: Doubts about programming

Simonr — Fri, 31 Jan 2020 07:11:23 GMT

[quote user="Anderson Silva"]I placed these periferical componentes in the opossite side of PCB (the nRF is in the top and the capacitors are in the bottom).[/quote]

I'm sorry, but what do you mean by this? Have you connected the components that should go on one side of the board to the other, I.E. left to right and vice versa? In that case, this is definitely the reason you're having trouble. If your nRF chip is on the wrong way, please try to desolder it and place it correctly.

Best regards,

Simon

RE: Doubts about programming

Anderson Silva — Thu, 30 Jan 2020 15:07:45 GMT

I've readed again the datasheet and I noted one thing that I haven't noted before...
I placed these periferical componentes in the opossite side of PCB (the nRF is in the top and the capacitors are in the bottom).
They are very close of respective nRF pins, but in opposite side of PCB.
I believe that it can be the reason for can't program it...
What do you think? Is it possible?

RE: Doubts about programming

Simonr — Thu, 30 Jan 2020 13:56:15 GMT

There shouldn't be any differences between the E0 and E1 build codes, these codes are just to track which supplier has manufactured the IC. Are the E0 and E1 connected identically HW-wise? On your schematics, there are some components that are crossed out in red, does that mean that they're not mounted? If so, I think you should mount L2 and L3 in your DCDC circuit. Are R28 and R29 just shorted, as SWDIO and SWDCLK need to reach the chip somehow?

Best regards,

Simon

RE: Doubts about programming

Anderson Silva — Thu, 30 Jan 2020 11:39:57 GMT

These jumpers are exacltly how I'm trying to programm the nRF52.
And bellow follows my circuit. It is very similar with reference design.
The marking code of the nRF that I'm using is "N52832 QFAA E1" (that I can't program). But I have other custom board with "N52832 QFAA E0" that I can program very well... Is there any diference related with this "E0" and "E1"?

RE: Doubts about programming

Simonr — Thu, 30 Jan 2020 09:56:42 GMT

It shouldn't be necessary to do anything different when your program an nRF52 the first time. Please make sure that your custom board is connected to the DK like in the picture below. I'd also like to see the schematics of your custom board so I can see that everything is connected correctly. If you don't want to share your schematic files publicly, please say so, and I will set this case to private mode so that only yourself and Nordic engineers will be able to see this case.

Best regards,

Simon

RE: Doubts about programming

Anderson Silva — Wed, 29 Jan 2020 18:39:45 GMT

This is exactly what I'm doing. But it doesn't works.
The programmer doesn't recognize the nRF52 and can't program it.
Is necessary to do something in the first programming? Because the programer says that is not recognizing it or the device is blocked (protected).
I tryied with different units but the results are the same.
And the problem is not with the PCB...
I'm not sure if is necessary to do something differente in the first programming to "unblock" it...
Thanks again
Regards

RE: Doubts about programming

Simonr — Wed, 29 Jan 2020 12:51:48 GMT

We recommend mounting all components stated in the reference circuitry (found here) before flashing and running your device to make sure it runs properly. The antenna components shouldn't be necessary to connect, but the DEC capacitors and the DCC components should be attached if you're using the DCDC regulator. The 32MHz crystal should be connected, but the LF crystal is optional as you can see. The reset pin can indeed be floating.

Best regards,

Simon

RE: Doubts about programming

Anderson Silva — Wed, 29 Jan 2020 11:02:21 GMT

I understood...
But I'm not sure about with one should I solder.... You wanna mean the capacitors connected with pins DEC1 (1), DEC3 (33), DEC2 (32), DEC4 (46), ANT (30) and inductors connectec with the pins DCC (47) ?
Is necessary to connect the cristal too?
The reset pin could be floating?

RE: Doubts about programming

Simonr — Tue, 28 Jan 2020 14:21:05 GMT

You should definitely mount all the surrounding caps and inductors before trying to program and power an nRF52 device. Turbo J is correct that external caps and inductors are necessary for the processor to start.

Best regards,

Simon

RE: Doubts about programming

Turbo J — Tue, 28 Jan 2020 12:26:15 GMT

Did you bother to put on the passives (caps, inductors) around the NRF52 chip?

The processor will only start when supplied properly - and some voltages require external caps (and inductors) to be present.