mmWave human presence for under $20?!

Hello, it seems that the issue may be related to the serial port of ESP32C3. Our preliminary solution is to use another UART serial port instead of the default D6/D7 pins. However, we have not had a chance to test it yet. We would appreciate it if you could provide feedback on this issue.

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This seems to have fixed the problem! Using D0/D1 on the Xiao, which corresponds to GPIO2/3.

New yaml. looks like this:

  id: uart_bus
  baud_rate:  115200
  rx_pin: 2
  tx_pin: 3

Hello Serena, any update on this issue, I bought 2 boards and both of em are having the same issue.

Hello, did anyone try using seeed static presence sensor with esp8266?


I am also tinkering with the seed lite sensor. I am not using Homeassistant at all ( maybe changing because it is getting more and more interesting ) instead using node red and openhab. I would like to configure my sensor with the help off ESPHome change the sensitivity settings and then want to run the sensor “standalone” again over mqtt.

Now my question:
Does the ESP save all the made settings? So that i can make the changes in Homeassistant and then using the sensor standalone again with the correct settings? Or does the sensor need to connect everytime to Homeassistant again at bootup to get the right parameters?

Bye the way going the way over the arduino ide and trying to change there the settings is way to much for most of the standard users out there ( at least for me ), I think.

Thanks for your effort to get a stable product out of it.

Best regards

with my code, and I think all codesets, the BHA / FDA sensor modules store the settings, not the ESP / Arduino controller (aka the MCU) though I’m not certain how it is with the lite variant. The ESP can of course override these settings each time or send “frames” to the radar module to change the settings. To give an example, if I were to take my ESP or Arduino (MQTT) code and flash an MCU with it and send certain settings such as sensitivity or fall detection off. I could then take that radar module and connect to another MCU of any type and it will read back these settings from the radar.

Interesting that Seeed states the following in their privacy policy:

“The Site has the obligation to provide personal information to the judicial organs and government departments in accordance with the relevant laws and regulations.”

That’s just reminding you that companies are subject to laws. Does it surprise you that that’s true, or that the policy has language reminding you?

It just reminds me that there is a lot of naivety amongst us. Who even bothers to read a privacy policy??
That companies are subject to laws is obvious. But what is shocking is that in certain countries companies are forced to provide personal customer information to their governments. Also raises the question exactly what is the extend of this obligation, whether it involves those apps that we are so keen to install on our phones and laptops.

Pretty much the extent of the obligation is, in most countries, if the government has a warrant and says give me the data, the company gives them the data.

Your only recourse is if the data is encrypted, and you’re the only one with the key, then it’s up to the government to deal with that…

Thanks for your respone, ive just jumped on the HA train now. Puhh what a work…

If this is the wrong place to ask, I apologize. Please direct me. =]

I have mostly plagiarized the Yaml posted in post 138, and also made the correction from post 142. Im using a seeed ESP32c3 with the seeed mmWave Human Static Presence Sensor. I have also had issues with the seeed ESP code not being completely erased between flashes, so I there is that.

I had trouble understanding how to add the library, but I figured it out well enough that the code did compile and install. My library may or may not be the most up to date version.

It all shows up in home assistant, but most values just return “Unknown”. Reading the wiki, as best as I can understand it, I think I need to connect the sensor to a usb serial bridge (Which I do have and know how to use) but I dont understand the next step? I would appreciate some help. =]

Slightly off-topic, and not under $20… The Screek MM-wave detector already has ESPHome installed.

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Have you got any experience with it?

Very little. But it only took 10 minutes to set it up and Home Assistant discovered it right away.

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I’ve heard some people have overheat issues, even in the above pic, your ESP temp seems a bit toasty but perhaps that’s normal… see the thread below for some details and perhaps solutions:

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Due to the more confined space, the temperature further increased when summer arrived, but such temperature is still within the normal operating range of the esp32. Recently we have optimized the wifi strategy through firmware and the processor energy saving settings, which has resulted in improved stability. At the same time we added heat sinks to the case to further optimize this temperature.
We are also refining a smaller sensor that actually gets the main temperature from the radar part, which is always heating up.


I have found and ordered this 60GHz Sensor from Micradar R60AMP1. I am trying to find any documentation available but my Google searches have brought very little information on UART input and output definition. It looks like the Seeed radars mentioned above, but perhaps other firmware. Is anyone familiar with this sensor?

I didn’t see this posted but seeed now has a full kit with case for 27 dollars. Slightly over but has a spot for another sensor using grove connection and website to flash so time saved might be worth the extra 7 dollars. You can swap out mmwave modules with other seed mmwave sensors also. Their wiki has the full yaml code



8 know it’s been a while but it looks like the pins match the seemed mmwave sensors. Check out the examples on the site below. It might even fit their kit (post above) and I think they might just sell the case and board. Would need a Xiao C3 though.

GitHub repo