dht-to-i2c-expander

A project that uses an ATmega8 to translate I2C to 16 DHT22 sensors.

We have many DHT22 sensors and didn't want to/couldn't connect them all to a Raspberry Pi due to lack of pins and lack of a robust implementation (we bitbanged it from userspace, which was meh). We therefore created a small breakout board with an ATmega8(L) on it to read the sensors and make readings available via I2C. Readouts are triggered via I2C by the bus master through setting bit 0x01 in the status register at 0x00.

Most of this stuff, including the resulting format and whatnot, is explained in main.c, so check that out.

License

MIT, but would be nice if you would link back here.