components/esp32-owb/README.md@b74b0e4902c3 (annotated)
components/esp32-owb/README.md
Sat, 20 Oct 2018 13:23:15 +0200
- author
- Michiel Broek <mbroek@mbse.eu>
- date
- Sat, 20 Oct 2018 13:23:15 +0200
- changeset 0
- b74b0e4902c3
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Initial checkin brewboard
| 0 | 1 | # esp32-owb |
| 2 | ||
| 3 | This is a ESP32-compatible C component for the Maxim Integrated "1-Wire" protocol. | |
| 4 | ||
| 5 | 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). | |
| 6 | ||
| 7 | Support for v2.1 is available on the [ESP-IDF_v2.1](https://github.com/DavidAntliff/esp32-owb/tree/ESP-IDF_v2.1) branch. | |
| 8 | ||
| 9 | ## Features | |
| 10 | ||
| 11 | This library includes: | |
| 12 | ||
| 13 | * External power supply mode (parasitic mode not yet supported). | |
| 14 | * Static (stack-based) or dynamic (malloc-based) memory model. | |
| 15 | * No globals - support any number of 1-Wire buses simultaneously. | |
| 16 | * 1-Wire device detection and validation, including search for multiple devices on a single bus. | |
| 17 | * Addressing optimisation for a single (solo) device on a bus. | |
| 18 | * 1-Wire bus operations including multi-byte read and write operations. | |
| 19 | * CRC checks on ROM code. | |
| 20 | ||
| 21 | This component includes two methods of bus access - delay-driven GPIO and RMT-driven slots. | |
| 22 | The original implementation used CPU delays to construct the 1-Wire read/write timeslots | |
| 23 | however this proved to be too unreliable. A second method, using the ESP32's RMT peripheral, | |
| 24 | results in very accurate read/write timeslots and more reliable operation. | |
| 25 | ||
| 26 | Therefore I highly recommend that you use the RMT driver. The GPIO driver should be considered deprecated. | |
| 27 | ||
| 28 | ## Documentation | |
| 29 | ||
| 30 | Automatically generated API documentation (doxygen) is available [here](https://davidantliff.github.io/esp32-owb/index.html). | |
| 31 | ||
| 32 | ## Source Code | |
| 33 | ||
| 34 | The source is available from [GitHub](https://www.github.com/DavidAntliff/esp32-owb). | |
| 35 | ||
| 36 | ## License | |
| 37 | ||
| 38 | The code in this project is licensed under the MIT license - see LICENSE for details. | |
| 39 | ||
| 40 | ## Links | |
| 41 | ||
| 42 | * [esp32-ds18b20](https://github.com/DavidAntliff/esp32-ds18b20) - ESP32-compatible DS18B20 Digital Thermometer component for ESP32 | |
| 43 | * [1-Wire Communication Through Software](https://www.maximintegrated.com/en/app-notes/index.mvp/id/126) | |
| 44 | * [1-Wire Search Algorithm](https://www.maximintegrated.com/en/app-notes/index.mvp/id/187) | |
| 45 | * [Espressif IoT Development Framework for ESP32](https://github.com/espressif/esp-idf) | |
| 46 | ||
| 47 | ## Acknowledgements | |
| 48 | ||
| 49 | Thank you to [Chris Morgan](https://github.com/chmorgan) for his contribution of adding RMT peripheral support for more reliable operation. | |
| 50 | ||
| 51 | Parts of this code are based on references provided to the public domain by Maxim Integrated. | |
| 52 | ||
| 53 | "1-Wire" is a registered trademark of Maxim Integrated. | |
| 54 |
