# Advanced RMT Transmit & Receive Example -- Simulate 1-Wire Bus
(See the README.md file in the upper level 'examples' directory for more information about examples.)
RMT peripheral has independent transmit and receive channels. We can simulate the [1-Wire](https://www.analog.com/en/technical-articles/guide-to-1wire-communication.html) bus by attaching a pair of transmit and receive channel to the same GPIO, and turning on the open-drain mode of the GPIO pad.
We've made the 1-Wire protocol implementation into a component called `onewire_bus`, which has been uploaded to the [ESP Component Registry](https://components.espressif.com/components/espressif/onewire_bus).
This example demonstrates how to use that `onewire_bus` library to read temperature from the [DS18B20](https://www.analog.com/media/en/technical-documentation/data-sheets/ds18b20.pdf) sensor. Likewise, the DS18B20 device is also made as a single component and pushed to the [ESP Component Registry](https://components.espressif.com/components/espressif/ds18b20).
One of the amazing feature that offered by the `onewire_bus` driver is that, is can support enumerate the devices on the bus, thus you can connect multiple DS18B20 sensors to the same bus and read their temperature one by one.
## How to Use Example
### Hardware Required
* A development board with any supported Espressif SOC chip (see `Supported Targets` table above)
* One or more DS18B20 sensors connected to the same bus by a 4.7 KΩ pull-up resistor
The GPIO number used in this example can be changed according to your board, by the macro `EXAMPLE_ONEWIRE_BUS_GPIO` defined in [onewire_example_main.c](main/onewire_example_main.c).
> **Note**
> Parasite power mode is not supported, you have to connect VDD pin to make DS18B20 functional.
### Build and Flash
Run `idf.py -p PORT flash monitor` to build, flash and monitor the project.
(To exit the serial monitor, type ``Ctrl-]``.)
See the [Getting Started Guide](https://docs.espressif.com/projects/esp-idf/en/latest/get-started/index.html) for full steps to configure and use ESP-IDF to build projects.
