ESP32_ChinaDieselHeater_Con.../lib/esp32-ds18b20/README_OWA.md

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# esp32-owb
This is a ESP32-compatible C component for the Maxim Integrated "1-Wire" protocol.
It is written and tested for version 3.0 of the [ESP-IDF](https://github.com/espressif/esp-idf) environment, using the xtensa-esp32-elf toolchain (gcc version 5.2.0, crosstool-ng-1.22.0-80-g6c4433a).
Support for v2.1 is available on the [ESP-IDF_v2.1](https://github.com/DavidAntliff/esp32-owb/tree/ESP-IDF_v2.1) branch.
## Features
This library 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 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.
* 1-Wire bus operations including multi-byte read and write operations.
* CRC checks on ROM code.
This component includes two methods of bus access - delay-driven GPIO and RMT-driven slots.
The original implementation used CPU delays to construct the 1-Wire read/write timeslots
however this proved to be too unreliable. A second method, using the ESP32's RMT peripheral,
results in very accurate read/write timeslots and more reliable operation.
Therefore I highly recommend that you use the RMT driver. The GPIO driver should be considered deprecated.
## Documentation
Automatically generated API documentation (doxygen) is available [here](https://davidantliff.github.io/esp32-owb/index.html).
## Source Code
The source is available from [GitHub](https://www.github.com/DavidAntliff/esp32-owb).
## License
The code in this project is licensed under the MIT license - see LICENSE for details.
## Links
* [esp32-ds18b20](https://github.com/DavidAntliff/esp32-ds18b20) - ESP32-compatible DS18B20 Digital Thermometer component for ESP32
* [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
Thank you to [Chris Morgan](https://github.com/chmorgan) for his contribution of adding RMT peripheral support for more reliable operation.
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.