65 lines
2.5 KiB
Markdown
65 lines
2.5 KiB
Markdown
# esp32-ds18b20
|
|
|
|
## Introduction
|
|
|
|
This is a ESP32-compatible C component for the Maxim Integrated DS18B20 Programmable Resolution 1-Wire Digital Thermometer device.
|
|
|
|
It supports multiple devices on the same 1-Wire bus.
|
|
|
|
It is written and tested for v2.1 and v3.0 of the [ESP-IDF](https://github.com/espressif/esp-idf) environment, using the xtensa-esp32-elf toolchain (gcc version 5.2.0).
|
|
|
|
## Dependencies
|
|
|
|
Requires [esp32-owb](https://github.com/DavidAntliff/esp32-owb).
|
|
|
|
## Example
|
|
|
|
See [esp32-ds18b20-example](https://github.com/DavidAntliff/esp32-ds18b20-example) for an example that supports single and multiple devices on a single bus.
|
|
|
|
## Features
|
|
|
|
In cooperation with the underlying esp32-owb component, this component includes:
|
|
|
|
* External power supply mode (parasitic mode not yet supported).
|
|
* Static (stack-based) or dynamic (malloc-based) memory model.
|
|
* No globals - support any number of DS18B20 devices on any number of 1-Wire buses simultaneously.
|
|
* 1-Wire device detection and validation, including search for multiple devices on a single bus.
|
|
* Addressing optimisation for a single (solo) device on a bus.
|
|
* CRC checks on temperature data.
|
|
* Programmable temperature measurement resolution (9, 10, 11 or 12-bit resolution).
|
|
* Temperature conversion and retrieval.
|
|
* Separation of conversion and temperature retrieval to allow for simultaneous conversion across multiple devices.
|
|
|
|
## Documentation
|
|
|
|
Automatically generated API documentation (doxygen) is available [here](https://davidantliff.github.io/esp32-ds18b20/index.html).
|
|
|
|
## Source Code
|
|
|
|
The source is available from [GitHub](https://www.github.com/DavidAntliff/esp32-ds18b20).
|
|
|
|
## License
|
|
|
|
The code in this project is licensed under the MIT license - see LICENSE for details.
|
|
|
|
## Links
|
|
|
|
* [DS18B20 Datasheet](http://datasheets.maximintegrated.com/en/ds/DS18B20.pdf)
|
|
* [1-Wire Communication Through Software](https://www.maximintegrated.com/en/app-notes/index.mvp/id/126)
|
|
* [1-Wire Search Algorithm](https://www.maximintegrated.com/en/app-notes/index.mvp/id/187)
|
|
* [Espressif IoT Development Framework for ESP32](https://github.com/espressif/esp-idf)
|
|
|
|
## Acknowledgements
|
|
|
|
Parts of this code are based on references provided to the public domain by Maxim Integrated.
|
|
|
|
"1-Wire" is a registered trademark of Maxim Integrated.
|
|
|
|
## Roadmap
|
|
|
|
The following features are anticipated but not yet implemented:
|
|
|
|
* Concurrency support (multiple tasks accessing devices on the same bus).
|
|
* Alarm support.
|
|
* EEPROM support.
|
|
* Parasitic power support.
|