ESP32 RF Test Tool and TX Tone Functionality

[Jerrold]

I'm trying to use an ESP32 to generate a 2.4 GHz continuous wave. I'm currently using the ESP32 RF Test Tool, which gives me the option to generate a continuous TX Tone in the WiFi test mode. It's exactly what I need, but unfortunately only allows me to use the 14 WiFi channels for my frequency. If I switch to BT test mode, I have access to all of the Bluetooth channels, but the output power is much lower, and I need the higher power from WiFi.

Therefore, I have two questions:

1. Is there a way for me to replicate the WiFi TX Tone from the ESP32 RF Test Tool programmatically in user code, using the ESP-IDF?
2. Is it possible to generate a TX Tone with an offset from the WiFi channel frequency? I have found that the TI CC3200 has this ability and I'm hoping to be able to do this with the ESP32.

Attached is just a screenshot of the ESP32 RF Test Tool.

Thanks for the help.

[goldzwm]

Did you find any way to do this in the end?
I'm looking into the same problem and can't find any resources.

[doragasu]

This feature could also save me a lot of time for some lab tests, so I dug a bit more into it without success. My findings in case anyone wants to try: the ESP32 ROM exports three functions with suspicious names:

* rom_start_tx_tone()
* rom_start_tx_tone_step()
* rom_stop_tx_tone()

The stop function takes one argument, the start_tx_tone_step() takes 6 arguments, and the start_tx_tone() apparently also takes 6 arguments (not completely sure about this). I played a bit with start_tx_tone() and start_tx_tone_step() feeding random values and couldn't get the device to output anything, so it will take either support from Espressif or someone smarter than me looking into this to figure out how these functions work (assuming they are the ones that output the tone).

[doragasu]

In an interesting turn of events, this seems to be supported by latest esp-idf (5.1), including documentation and an usage example!

Unfortunately only ESP32-S3 and ESP32-C3 support this feature right now, so for the good old ESP32, we still have no way to do it. I have opened a GitHub issue to see if we can get the ESP32 supported.