Understanding channel select on radio test example

RE: Understanding channel select on radio test example

Andreas — Fri, 08 Nov 2019 08:51:01 GMT

Yes, either radio_modulated_tx_carrier or radio_unmodulated_tx_carrier, depending on if you want modulated carrier or not. The channel is determined when you call the function, as an example:

void radio_modulated_tx_carrier(RADIO_TXPOWER_TXPOWER_Pos4dBm, RADIO_MODE_MODE_Ble_1Mbit, 40)

will start the radio on channel 40, in BLE 1Mbps mode at 4 dBm. Changing the frequency by pushing a button takes some work, you need to add that to the GPIOTE button event handler.

Best regards,

Andreas

RE: Understanding channel select on radio test example

Andreas — Fri, 08 Nov 2019 08:46:33 GMT

Hi,

See the testing section of the example documentation:

Test the Radio Test Example application by performing the following steps:

Compile and program the application.
Start a terminal emulator like PuTTY (recommended) with the related Terminal settings and UART and USB settings. The text "Radio test example started." appears at the top of the terminal.
Open a serial connection to the COM port used by the tester board. A command prompt is displayed.
Type any of the CLI commands described above. An output text is displayed in the terminal emulator window, and the sweep or the signal is started.
Depending on the testing method:
- Use a spectrum analyzer to confirm the behavior of the radio module.
- Use a second board configured in the same mode as the first one to receive the transmission, and type print_rx to print the RX data received from the other board.

As for step #2, see the link, but note that you need to go to the session category to start the UART terminal. If you need to figure out what COM port your DK is, see the device manager in Windows.

Best regards,

Andreas

RE: Understanding channel select on radio test example

Tandon — Thu, 07 Nov 2019 18:27:10 GMT

How would I use the UART? nRF Connect app? I am a little lost. Thank you

RE: Understanding channel select on radio test example

Tandon — Thu, 07 Nov 2019 15:50:23 GMT

I am guessing its radio_modulated_tx_carrier correct? How can I set the separate channels?

RE: Understanding channel select on radio test example

Tandon — Thu, 07 Nov 2019 15:48:35 GMT

Thanks for the lighting quick response,

1) I am planning on using GPIOTE button in order to jump through the channels instead of UART. What line of code should I use to set the transmit channel? Where my assumptions correct for the channels?

RE: Understanding channel select on radio test example

Andreas — Thu, 07 Nov 2019 15:43:24 GMT

Hi,

1. The sweep function is not quite what they are after, they are after a way to set the transmitter to 2402 MHz, 2440 MHz and 2480 MHz. The radio test example comes with a UART CLI that lets you configure this through a terminal, no reason to worry about the source code. Of course you could make separate images that set up the transmitter upon startup, it is all up to what you and the test house prefer.

2. No the receiver would need to run the start_rx command, with the same bitpattern, mode and on the same channel. You then need to use the start_tx_modulated_carrier or start_duty_cycle_modulated_tx on your DUT. You do not need to do this though, the transmitter just needs to transmit 'something', so you might find the RSSI App in nRF Connect for Desktop more convenient to prove this (this uses your 2nd DK as a makeshift spectrum analyzer).

Best regards,

Andreas