I am currently developing a ATTiny1614 + RFM95W + BME280 environment sensor which will send data to The Things Network via an existing gateway. The new ATTiny boards support hardware SPI which is what I am using here to communicate between the uC and different modules.
The hardware I selected:
- Self-designed ATTinyX14 Development Board (Schematics to be added)
- RFM95W with antenna
- BME280 3.3v with SPI interface (6-pin board)
Tools I am using for development:
- Atmel Studio 7
- Atmel-ICE / MPLAB® PICkit 4
- Kingst Logic Analyzer
- For BME280 take out all the resistors on the surface to reduce power consumption by ~450uA. We are using SPI so no pull-up resistors are needed here.
- I haven't done anything on OTAA, and currently keys are hard-coded.
- Copy
key.example.hfile and name itkey.h, then replace the values there.
I don't have a precise tool to measure low current, but based on my multimeter:
- Wake up time lasts for about 0.2s, not sure the total power consumption, but peak current is around 60mA.
- Sleep current is around 7uA.
