about nRF52-ble-long-range-demo

[Dai.Ima]

Hi,

I'm trying to measure the communication distance with Coded PHY using two nRF52840s and the demo software below,

but there are some problems. They are shown below.

https://github.com/NordicPlayground/nRF52-ble-long-range-demo

a. Buttons and LED configurations are described in nRF52-ble-long-range-demo/readme.md, but LED doesn't light up after writing the specified hex file.

　Are there other settings?

b. I understand that I need a Serial Port Viewer (for example Tera Term or Realterm) to see RSSI,　but is there anything else I should do? For example, program modifications,

   and When using the Serial Port Viewer, is it necessary to supply power to the board with a battery or the like?

c. When the writing of the software is completed, the power of the board is turned off, and it is restarted, the software disappears. Is this due to lack of memory?

It's my first time working with a board like this, so sorry for the elementary questions.

Best Regards,

[ovrebekk]

Hi

c. When the writing of the software is completed, the power of the board is turned off, and it is restarted, the software disappears. Is this due to lack of memory?

This shouldn't happen, no. The firmware is stored in flash memory, which will be retained during power down. 

If you press the reset button on the board after it wakes up will the code start running then?

Did you remember to reconnect the RTT viewer application after powering up the board?

Best regards
Torbjørn

[Dai.Ima]

Hi,

Thank you for your reply.

 I checked the board, the firmware was stored in flash memory.

I think I misunderstood that the firmware update method was wrong and the LED didn't light up,

so the firmware wasn't saved.

Best regards

[ovrebekk]

Hi

Does that mean you now got everything working, or do you still have some issues getting the demo to run?

Best regards
Torbjørn

[Dai.Ima]

Hi,

I got everything working.

But I have a question. RSSI display in Central. Is this Central's RSSI or Peripheral's RSSI?

As next step, I added FEM between A and nRF82540 on Central side, but RSSI didn't change with or without FEM. I want to determine whether it is due to the operation of FEM.

Best Regards,

[ovrebekk]

Hi 

The RSSI displayed on the central side should be the signal strength of the incoming signal from the peripheral. 

In other words if you add a FEM on the central side it needs to have an LNA (rather than a PA) to boost the RSSI seen on the central side. 

Best regards
Torbjørn

[Dai.Ima]

Hi

Thank you for your support.

I understand  the RSSI displayed on the central side and it needs to have an LNA  to boost the RSSI seen on the central side. 

When I use LNA or FEM, I know that I need a signal to control the LNA. Does the nRF52840-DK have ports for extracting control signals like TXEN(Tx enable) and RXEN(Rx enable)? If it doesn't exist, do we have to modify it ourselves?

Best Regards,