JLink Voltage value for flasdhing change

[simon1516]

Hi,

I have a custom board with nrf52833 I would like to flash with custom firmware. I would like to flash this board by "P19 debug out connector" from DK.

How can I do the power supply of the external board? VDD of external Board has to be 1,8V!

In my opinion I have two options:

1.: Power by soldering bridge SB47 of DK. In this case, I have to customize VDD of DK to 1,8V I think. How can I do this?

2.: Power the custom board by external supply to VDDH (5V) and NOT soldering bridge SB47 of DK. Does this works? What value is VDD in this case? It´s not configured to this time.

Thanks in advance

Simon

[awneil]

simon1516 said:

"P19 debug out connector" from DK

That does not support a 1.8V target.

You will need a real J-Link for that.

(or other 1.8V-capable programmer)

[simon1516]

hmm...my information was, that programming voltage can be adjust by changing VDD, which is configurable. So if VDD of DK = 1,8V, the board is able to flash with these 1,8V. Isn´t that right?

Which alternate programmer can you recommend?

[simon1516]

haakonsh said:

Call 'nrfjprog -f nrf52 -e' in cmd. This will erase the UICR register REGOUT0 that contains the settings for REG0. 

I did that (s. Screenshot cmd, I think it was successful because confirmation message) but I can measure about 2.95V level of VDD Pin from nrf52833 DK furthermore.

Is there something else I have to do? Thanks for your help! I already repowered the DK by USB.

[haakonsh]

Did you erase the target on your custom board or on the DK?

[simon1516]

There was no target connected to dk board, so I erase the dk board

[simon1516]

I had another brand new 52833 DK board here, the first connect to USB power and execute "nrfjprog -f nrf52 -e" doesn´t work for changing VDD voltage. Can I try something other? 

[haakonsh]

It's the target board you need to erase since they are the ones who have a  REGOUT0 register set to 3V3. 

[simon1516]

hmm, I don´t know if you´re understanding my issue.

The target board has a few components, working with 1,8V connected to VDD. So in my understanding, I can´t connect a 3V programmer (=nRF52833 DK board) to this target. I need a programming voltage by 1,8V, that nothing happens to the components of the target board. I power the target boards by nRF52833 DK board. The voltage from debug out interface is connected to VDD of the target. So before first connection, I have to make sure, that the programming voltage (VDD of DK) board ist correct.

Therefore, I have to customize the configuration of DK board. If I´m completly wrong, please tell me :-)

[haakonsh]

simon1516 said:

I power the target boards by nRF52833 DK board.

 You need to power the target board with 1.8V.
 

simon1516 said:

I can´t connect a 3V programmer (=nRF52833 DK board) to this target.

simon1516 said:

Yes, I use nRF52833 DK, this also support 1.8V targets:

 https://infocenter.nordicsemi.com/index.jsp?topic=%2Fug_nrf52833_dk%2FUG%2Fnrf52833_DK%2Fhw_debug_out.html
"The voltage supported by external debugging/programming is VDD voltage. Normally, this is 3 V when running from USB, but if the onboard nRF52833 SoC is supplied from either USB or Li-Ion, the nRF power source switch (SW9) is in either Li-Po or USB position, and VDD can be set by the nRF52833 firmware. Make sure the voltage level of the external board matches the VDD of the nRF52833 DK."

If you've erased the nRF52833 on the DK, power the DK from the Li-po or nRF USB inputs, and powered the external board at 1.8V, you should be able to interface the debugger with the external board.

[simon1516]

haakonsh said:

If you've erased the nRF52833 on the DK, power the DK from the Li-po or nRF USB inputs, and powered the external board at 1.8V, you should be able to interface the debugger with the external board.

ahh, now I have voltage level at 1,8V on nrf52833 DK. I not realized that I had to use the nRF USB Input. I used always the standard USB connection. But now, when I use nRF USB, I can´t connect/programming by J-Link. Can you tell me what to do making this work?

Thanks in advance.

[haakonsh]

Have you flipped the power switch to USB?

[simon1516]

Yes