esp-idf/examples/system/ulp_riscv/ds18b20_onewire
Djordje Nedic facab8c5a7 tools: Increase the minimal supported CMake version to 3.16
This updates the minimal supported version of CMake to 3.16, which in turn enables us to use more CMake features and have a cleaner build system.
This is the version that provides most new features and also the one we use in our latest docker image for CI.
2022-06-01 06:35:02 +00:00
..
main ulp: refactor ulp component 2022-01-27 11:54:42 +05:30
CMakeLists.txt tools: Increase the minimal supported CMake version to 3.16 2022-06-01 06:35:02 +00:00
README.md RISCV-ULP: Add DS18B20 1wire RISCV-ULP example 2021-06-25 11:26:39 +08:00
sdkconfig.defaults ulp: refactor ulp component 2022-01-27 11:54:42 +05:30

Supported Targets ESP32-S2

ULP-RISC-V DS18B20 Temperature Sensor OneWire Communication

This example demonstrates how to program the ULP-RISC-V co-processor to read temperature from a DS18B20 temperature sensor over 1-Wire. When the measurement exceeds the limit set(32.5 degrees) the co-processor will wake up the main CPU from deep-sleep and the main CPU will print the temperature measurement.

Hardware Required

  • A development board with a SOC which has a RISC-V ULP coprocessor (e.g., ESP32-S2 Saola)
  • A USB cable for power supply and programming
  • A DS18B20 temperature sensor

Example connection :

ESP Dev-kit DS18B20
GPIO4 DQ
VCC 3.3V VDD
GND GND

Example output

Not a ULP wakeup, initializing it!
Entering in deep sleep

...

ULP-RISC-V woke up the main CPU, temperature is above set limit!
ULP-RISC-V read temperature is 32.562500
Entering in deep sleep

...

ULP-RISC-V woke up the main CPU, temperature is above set limit!
ULP-RISC-V read temperature is 33.000000
Entering in deep sleep