DS18B20 for the STM32F0 using libopencm3

Introduction

A simple driver written for libopencm3 and stm32f0, it was written from first principles and uses a GPIO to read and write bits to the DS18b20.

Limitations:

• It ignores the ROM Search therefore can only have a single ds18b20 sensor on each bus (but you can use multiple buses)
• It uses NOP for some of its timing which is probably not ideal
• The timings are rough, it could need some optimisation (but works with the fake ds18b20s I have.)

References

• https://teslabs.com/openplayer/docs/docs/other/ds18b20_pre1.pdf
• https://www.circuitbread.com/tutorials/embedded-c-programming-with-the-pic18f14k50-12-digital-thermometer
• https://www.analog.com/media/en/technical-documentation/data-sheets/DS18B20.pdf
• https://www.st.com/en/microcontrollers-microprocessors/stm32f030k6.html
• http://libopencm3.org/docs/latest/stm32f0/html/group__gpio__file.html#ga8970f778a63c9d78ffd8d4d36628c7e1