ESP-NOW example does not work with any other channel than 0 and 1 (IDFGH-8090)

[PilnyTomas]

Environment

• Development Kit: ESP32-C3-DevKitC-02
• Kit version (for WroverKit/PicoKit/DevKitC): v1.1
• Module or chip used: ESP32-C3-WROOM-02
• IDF version : v5.1-dev-224-g4d14c2ef2d
• Build System: idf.py
• Compiler version : 11.2.0
• Operating System: Linux - Fedora
• Using an IDE?: No
• Power Supply: USB

Problem Description

ESP-NOW example outputs error and does not work when the channel is to anything but 0 or 1

Expected Behavior

If this is expected behavior, please update the example and its documentation to prevent confusion.
If the channel really is supposed to be changeable, then please fix the reason.

Actual Behavior

Does not work.

Steps to reproduce

1. Go to ESP-NOW example in IDF examples/wifi/espnow
2. In menuconfig go to Example Configuration ---> Channel and set number 2 or more
3. Flash and run
4. Observer errors:

E (5499) ESPNOW: Peer channel is not equal to the home channel, send fail!
E (5499) espnow_example: Send error

Code to reproduce this issue

ESP-NOW example in IDF examples/wifi/espnow

Optionaly you can add extra debug output at the end of the function example_wifi_init - (under line 57)

    uint8_t primaryChan = 0;
    wifi_second_chan_t secondChan = WIFI_SECOND_CHAN_NONE;
    esp_wifi_get_channel(&primaryChan, &secondChan);
    ESP_LOGI(TAG, "CONFIG_ESPNOW_CHANNEL=%d; WiFi is on channel %d  ", CONFIG_ESPNOW_CHANNEL, primaryChan);

A related issue in Arduin-ESP32 espressif/arduino-esp32#2653
Probably related #4311

[MaxwellAlan]

Hi @PilnyTomas

Thanks for the bug reporting. We will optimize ESP-NOW example.
You can add below line after esp_wifi_start:
esp_wifi_set_channel(CONFIG_ESPNOW_CHANNEL,0);

[PilnyTomas]

Hi, thanks for your reply.
Will you update only the example, or are you planning to implement the ability to change a channel into ESP-NOW API?

[MaxwellAlan]

Hi @PilnyTomas
We will only update the example. ESP-NOW's channel should obey the STA/AP's channel.

[garykuipers]

That is incorrect, I am currently running on channel 11.

"""
Serial.println("SETUP ESPNOW");
WiFi.mode(WIFI_STA);
WiFi.disconnect(true);
esp_wifi_set_mode(WIFI_MODE_STA);
delay(100);

    // Initialize WiFi
    wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
    esp_wifi_init(&cfg);
    esp_wifi_start();
    // Initialize ESP-NOW
    esp_err_t initResult = esp_now_init();
    if (initResult != ESP_OK) {
        Serial.printf("ESP-NOW initialization failed with error: %d\n", initResult);
        return;
    }

    // Set the channel for 2.4 GHz
    esp_err_t result = esp_wifi_set_channel(storage.channel, WIFI_SECOND_CHAN_NONE);
    if (result == ESP_OK) {
        Serial.println("Channel set successfully");
    } else {
        Serial.printf("Failed to set channel with error code: %d\n", result);
        // TODO: handle init error
    }
    Serial.println("SETUP ESPNOW: setup OK");

    // Verify the channel setup (This does not work! The communication works even though this says the channel is different)

// uint8_t current_channel;
// esp_wifi_get_channel(&current_channel, NULL);
// if (current_channel == storage.channel) {
// Serial.printf("Channel verification successful: Current channel is %d\n", current_channel);
// } else {
// Serial.printf("Channel verification failed: Expected %d, but got %d\n", storage.channel, current_channel);
// }

"""