I have a big ziplock bag full of breakout boards I bought on Taobao. I’m not totally sure what’s in there, so I’m just pulling out a random one every few days to do a demo.
It’s not a coincidence that the first breakout is a SI7021/HTU21/STH21/HDC1080 I2C humidity and temperature sensor. I have more than 30 of these boards for reasons I don’t recall.
The demo is in the firmware manual (still rebuilding at the moment). I also added I2C mode macro (2) which reads the temperature and humidity, the serial number and the chip firmware version.
This week I added a demo of a TSL2561 light/lux sensor. This chip is a little old, but there’s still tons of them out there on Aliexpress breakout boards. I had fun showing the math to calculate the value, most walk throughs just toss you a library and call it a day. I enjoy looking into the magic that makes it all happen.
Today we have a nice write-up from @dreg on using the AT24C256 I2C EEPROM. This inexpensive chip adds 32K bytes of permanent storage to your project, and full featured breakout boards are around $2 on AliExpress.
