# openthread / cli — Coprocessor
Runs a full OpenThread CLI (`ot ...`) on the host. The co-processor is the 802.15.4 **Radio Co-Processor (RCP)**: the host drives the RCP lifecycle over ESP-Hosted (RPC) and exchanges 802.15.4 (spinel) traffic over a **dedicated UART**. Adapted from `esp-idf/examples/openthread/ot_cli`.
## Supported Platforms and Transports
### Supported Coprocessors
OpenThread uses an 802.15.4 radio co-processor (RCP).
| Coprocessor | ESP32-C6 | ESP32-H2 | ESP32-H4 | ESP32-C5 |
| :---------: | :------: | :------: | :------: | :------: |
| Support | Yes | Yes | Yes | Yes |
### Supported Host Devices
| Host Device | ESP32-P4 | ESP32-H2 | Other MCUs | Linux |
| :---------: | :------: | :------: | :--------: | :---: |
| Support | Yes | Yes | [Yes](https://github.com/espressif/esp-hosted/blob/master/docs/getting-started-mcu.md) | [Yes](https://github.com/espressif/esp-hosted/blob/master/docs/getting-started-linux.md) |
### Supported Connection buses
| Connection bus | SDIO | SPI Full-Duplex | SPI Half-Duplex | UART |
| :------------- | :--: | :-------------: | :-------------: | :--: |
| Linux host | Yes | Yes | No | No |
| MCU host | Yes | Yes | Yes | Yes |
The co-processor runs as the OpenThread **RCP** (Wi-Fi off). Select the ESP-Hosted transport (used for RPC control):
```bash
cd examples/openthread/cli/cp
idf.py set-target esp32c6
idf.py menuconfig
```
```text
Component config
└── ESP-Hosted
└── Configure coprocessor
└── CP transport
├── Communication bus (co-processor <== bus ==> host)
│ ├── ( ) SPI Full Duplex
│ ├── (X) SDIO <── default
│ ├── ( ) SPI Half Duplex ← MCU host only
│ └── ( ) UART ← MCU host only
└── SDIO Configuration ← clock, GPIOs, checksum (defaults OK)
```
The RCP feature and its 802.15.4 spinel UART (to the host) live under Features:
```text
Component config
└── ESP-Hosted
└── Configure coprocessor
└── Features
└── [*] OpenThread RCP (Radio Co-Processor)
├── [*] Auto-initialise OpenThread feature at boot
└── OpenThread Transport
├── (X) UART <── default (spinel to host)
├── (1) UART Port to Use
├── (21) TX GPIO number (ESP32-C6)
├── (20) RX GPIO number (ESP32-C6)
└── (460800) Baud Rate
```
The RCP dependency config is **pre-set in `cp/sdkconfig.defaults`** (do not remove):
```text
CONFIG_ESP_HOSTED_CP_FEAT_OPENTHREAD=y # ESP-Hosted OpenThread RCP feature
CONFIG_OPENTHREAD_ENABLED=y # OpenThread stack
CONFIG_OPENTHREAD_RADIO=y # Radio-Only (RCP) device
CONFIG_ESP_HOSTED_CP_FEAT_WIFI=n # Wi-Fi off on the RCP
```
`CONFIG_OPENTHREAD_RADIO=y` corresponds to *Component config → OpenThread → Thread Core Features → Thread device type → Radio Only Device*. Then flash and monitor:
```bash
idf.py -p <cp_usb_serial_port> flash monitor
```
<!-- generated from ../README.md — edit that file, not this one -->
To create a project from this example, run:
idf.py create-project-from-example "espressif/esp_hosted=3.0.2:openthread/cli/cp"