ESP-NOW: Enable Long Range Mode (802.11LR)

[frederictobiasc]

Hi, I played around with the examples/src/bin/esp_wifi_esp_now.rs example. However, I noticed that the range seems quite limited.

In ESP-IDF, there is a long range mode configurable.

Could you please provide an example how to activate this in a project using esp-wifi?

I found a Protocol enum containing the right protocol. I'm just not sure how to manually initialize the Wi-Fi PHY in LR mode and use ESP-NOW on top.

[bjoernQ]

There should be set_mode introduced in this PR: esp-rs/esp-wifi-sys#156

[frederictobiasc]

Hi @bjoernQ and thanks for your response!
I branched off of the esp_wifi_esp_now.rs example.
When I'm calling set_mode() like follows, it panics:

#[entry]
fn main() -> ! {
    esp_println::logger::init_logger_from_env();

    let peripherals = Peripherals::take();

    let system = SystemControl::new(peripherals.SYSTEM);
    let clocks = ClockControl::max(system.clock_control).freeze();

    #[cfg(target_arch = "xtensa")]
    let timer = esp_hal::timer::timg::TimerGroup::new(peripherals.TIMG1, &clocks, None).timer0;
    #[cfg(target_arch = "riscv32")]
    let timer = esp_hal::timer::systimer::SystemTimer::new(peripherals.SYSTIMER).alarm0;
    let init = initialize(
        EspWifiInitFor::Wifi,
        timer,
        Rng::new(peripherals.RNG),
        peripherals.RADIO_CLK,
        &clocks,
    )
    .unwrap();
    
    let (device, token) = esp_wifi::esp_now::enable_esp_now_with_wifi(peripherals.WIFI);
    let  (mut wifidevice,mut controller) = esp_wifi::wifi::new_with_mode(&init,device,esp_wifi::wifi::WifiStaDevice).unwrap();
    controller.set_mode(esp_wifi::wifi::Protocol::P802D11LR).unwrap();
    let mut esp_now = esp_wifi::esp_now::EspNow::new_with_wifi(&init, token).unwrap();
    ...
}

serial output:

WARN - unsafe { esp_wifi_set_protocol(mode, protocol as u8) } returned an error: 258



!! A panic occured in 'src/main.rs', at line 51, column 62:
PanicInfo {
    payload: Any { .. },
    message: Some(
        called `Result::unwrap()` on an `Err` value: InternalError(EspErrInvalidArg),
    ),
    location: Location {
        file: "src/main.rs",
        line: 51,
        col: 62,
    },
    can_unwind: true,
    force_no_backtrace: false,
}

Backtrace:

0x42001280
0x42001280 - main
    at ??:??
0x42000102
0x42000102 - hal_main
    at /home/user/.cargo/registry/src/index.crates.io-6f17d22bba15001f/esp-hal-0.18.0/src/lib.rs:520

Do you have an idea how to set the mode correctly? I'm using the ESP32-C3 if that's relevant.

Off-topic: To me, the name set_mode seems unfitting. Wouldn't set_protocol be more concise in this case? Wi-Fi mode usually refers to AP or STA.

[bjoernQ]

I had a look and besides the misleading naming I think that function has additional problems

1. casting protocol to u8 doesn't result in a value compatible with protocol_bitmap which is required by esp_wifi_set_protocol
2. esp_wifi_get_mode gets a mode but esp_wifi_set_protocol takes wifi_interface_t as the first parameter

And another thing is that there should also be a function to set it for esp-now without needing the wifi-controller

I will create an issue from this discussion to fix all of this. Thanks for bringing up this topic

[frederictobiasc]

Hi @bjoernQ!
I noticed you fixed this in #1742 !
Thank you a lot!