Thread by @dcuthbert

It's a Sunday.
Kids are playing Lego
Wife is chilled

Guess this means it's teardown and tinker time with IKEAs indoor pollution sensor

Ok it's pretty well-designed. David Wahl is the designer, who's responsible for a lot of pretty damn good designs. Has usb-c to power but doesn't come with a cable.

Inside the beast.

Main heart is a Eastsoft ES7P001FGSA MCU. So far can only find the datasheet in Chinese. But it has the pinouts so that's all I need I guess for now

Connected to the PCB is the PM 2.5 sensor and fan. This is a PM1006 v1.1 sensor

Always handy when they silkscreen the test points

Soldered on a wire for easier access to GND and plugged in the PCBites

Added some wires to make it easier later on

Slight delay due to kids wanting to go and BMX.. box back together with wires and I'll hopefully work out what and how later on

Normal healthy reading

Unhealthy smoke reading

Amber reading

The PM1006K receives 11 02 0B 01 E1 from the MCU and sends out the results

I guess tomorrow I could add some wires to the following pins on the MCU but not 100% sure what else it would give me, but hey, I'm on holiday so...

Scratching around I've managed to find this.

This means I can take those readings and push them into this and up to @adafruit's IO

The design of this is actually super impressive. It's easy on the eye, the LED panel works very well and the MTTF is + 5 years, which for a tenner is bloody amazing.

and it used usb-c and not the funny older ones like most do.

Because when you have the itch over how a pm 2.5 sensor works, you need to scratch it hard journals.plos.org/plosone/articl…

Carrying on exploring. Wanted to see the MCU request the values from the PM and the returned values. First up with Sally the oscilloscope.

Then with the @saleae

You can see 5 bytes being sent by the MCU, 11 2 0b 01 E1, which takes 5.01 ms to get the response back.