Custom PCB: How to quick check if BLE is working? nRF51822AB

[Stephan]

Hi guys,

I hope you can answer my question: I made myself a custom pcb for testing purpose. I can program the nRF51822 just fine. Thats the actual state right now.

In combination with the nRF51822-EK: How can I just quick check if my BLE is working? I just want to kinda sniff, if I got RF-Output. It doesn't need to be a connection. I just want to be sure, that RF works before I'm getting into SW-debugging and API and stuff like that.

How can I check that? Is there a plain, simple solution?

Regards, Stephan

[Tom Harrah]

I use the simple code in led_radio_example. The USB dongle code transmits a packet and the EVK sample code receives the packet. I've modified the code somewhat to go in both directions, but the simple sample code Nordic supplies works. So load the USB dongle that comes with the EK with the led_radio_example code for the dongle, and load your PCB with the led_radio_sample code for the EVK board. If you have an LED or scope you can modify the code to toggle the IO upon receiving a packet, or just set a break point in the debugger. You then need to open a serial port terminal to the USB dongle and type 0 or 1 to send the packet. These packets use the 2mpbs Nordic RF mode and are not BLE compatible, but they show that the RF hardware is working OK. But, it is best to modify the code to send both ways, I once had a hand soldered PCB that could receive but would not transmit until I cleaned up the soldering on the nrf51822 chip.

[Joshua Stephens]

If you have a newer iphone, I've found a very good tool to use is LightBlue on the iphone app store.

[Frank Zhao]

I have a RF Explorer, a dirt cheap spectrum analyzer. If I run the DTM example, I can clearly see the energy at the frequency that the nRF is transmitting at.

It's a cool toy if you just want to test out stuff like this, also useful for setting up WiFi.

This doesn't check much, but at least you know the PLL is working

[Alex]

Simplest, turn on the radio with this:

NRF_RADIO->SHORTS = RADIO_SHORTS_READY_START_Msk; NRF_RADIO->FREQUENCY = channel; NRF_RADIO->TASKS_RXEN = 1;

Then check radio output with any handy 2.4GHz spectrum analyzer and antenna :)

Slightly more complex, set up radio_test_example from the SDK (and set up your board to talk with uart), then use uart commands to control radio. If you have a BLE test rig such as Anritsu that can be hooked up to the uart as well, enabling BLE DTM.

My first try, BLE wasn't working but the radio was just fine, due to bad crystal. That's why it seems best to test radio directly without BLE first. Something to watch out for, anyway.

[Stephan]

Hi guys,

wow, thanks for all that cool feedback! Really nice hints here! My problem is that I can program the nRF51822 just fine with the SoftDevice and all but I can't get any RF-Output of it. ATM I dont know if it's just soldered badly or if the mistake is somewhere else....

But since I do it as a hobby, unfortunately I do not own $$$-RF-Teststands ;)

So I might just try to set up a UART example to see if the chip is working. Maybe some blinking LEDs and stuff like that.....

I'm wondering why the heck it won't work, though! :(