# Wi-Fi iperf — Coprocessor
Wi-Fi throughput benchmark. The Wi-Fi radio runs on the **coprocessor**; the **host** runs the upstream IDF `wifi/iperf` console app, with its `esp_wifi_*` calls routed to the coprocessor over ESP-Hosted. Associate with an AP, then drive TCP/UDP iperf from the console to measure end-to-end throughput across the hosted transport.
`mcu_host/main/iperf_example_main.c` is the upstream IDF `wifi/iperf` example, unchanged; the hosted layer adds only dependency wiring and throughput-tuned host `sdkconfig.defaults`.
## Supported Platforms and Transports
### Supported Coprocessors
| Coprocessor | ESP32 | ESP32-C Series | ESP32-S Series |
| :----------: | :---: | :------------: | :------------: |
| Support | 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 |
## Scenario
The host associates as a Wi-Fi station through the coprocessor, obtains an IP over the hosted netif, then drives iperf/ping from its console to benchmark the link.
```mermaid
sequenceDiagram
participant App as Host (iperf console)
participant CP as Co-processor (Wi-Fi)
participant AP as Access Point / peer
App->>CP: connect to AP (esp_wifi_* over RPC)
CP->>AP: associate + authenticate
App-->>App: IP_EVENT_STA_GOT_IP (got IP)
App->>AP: iperf -c / -s (TCP/UDP throughput over the hosted transport)
```
The Wi-Fi radio runs on the co-processor firmware (`CONFIG_ESP_HOSTED_CP_FEAT_WIFI=y`, preset in `cp/sdkconfig.defaults`) — no extra option to enable. Select the transport (**SDIO** gives the best throughput):
```bash
cd examples/wifi/iperf/cp
idf.py set-target esp32c5
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 CP dependency config is **pre-set in `cp/sdkconfig.defaults`** (do not remove):
```text
CONFIG_ESP_HOSTED_CP_FEAT_WIFI=y # Wi-Fi (default CP feature)
CONFIG_BT_ENABLED=n # BT off (unused by this example)
```
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:wifi/iperf/cp"