Did you know that the LD2410 can be wired directly into an ESP32 or equivalent because it operates at the 3V3 level and has an RTC GPIO that can be used as a wakeup pin? This is a huge upgrade from the LTR5-series of light sensing chips which all use the I2C protocol, because those need a UART chip on the device to handle the clock signal with a 5V open drain, despite being an easier 2-wire implementation. The send protocol of I2C slave devices are much simpler than the 1-wire or Dallas protocol used for multiplexing sensors, and relies on sending information bits in 60microsecond intervals when the clock bit is high, this ensures…
$15.99 for two LD2410 is a bargain considering I’ve been looking a presence sensors for HA and they easily cost $60+ each. This is legitimately useful information!
Do you only need the ESP and presence sensor or is extra circuitry needed? I can probably print out some type of enclosure.
You can get them much cheaper than that on AliExpress hehe, though you might pay twice for quality. And yep you can wire them straight into each other, no pull-ups or nothing!
Caveats:
I got the LD2410s variant because I think it’s the only one that actually operates at 3v3, but unfortunately it’s not quite supported by ESPhome yet so I’ve been having issues getting it to do anything with HA. Methinks stick with 5V versions for now and use a voltage regulator for the GPIO since the ESP32 is not 5v tolerant for GPIO inputs (or: use a Raspberry Pi which can handle anything).
Do not use the brand new spanking ESP32C6 for that sweet sweet BLE and Zigbee functionality, because despite the arduino framework saying they support it in practice you’ll have to default to using the idf-esp framework, which isn’t a huge issue but does seem to throw me stranger errors.
Did you know that the LD2410 can be wired directly into an ESP32 or equivalent because it operates at the 3V3 level and has an RTC GPIO that can be used as a wakeup pin? This is a huge upgrade from the LTR5-series of light sensing chips which all use the I2C protocol, because those need a UART chip on the device to handle the clock signal with a 5V open drain, despite being an easier 2-wire implementation. The send protocol of I2C slave devices are much simpler than the 1-wire or Dallas protocol used for multiplexing sensors, and relies on sending information bits in 60microsecond intervals when the clock bit is high, this ensures…
(don’t drink coffee on the train)
(well now i gotta find a train and drink coffee on it)
$15.99 for two LD2410 is a bargain considering I’ve been looking a presence sensors for HA and they easily cost $60+ each. This is legitimately useful information!
Do you only need the ESP and presence sensor or is extra circuitry needed? I can probably print out some type of enclosure.
You can get them much cheaper than that on AliExpress hehe, though you might pay twice for quality. And yep you can wire them straight into each other, no pull-ups or nothing!
Caveats: