automatic light sleep

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#automatic light sleep

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alex (he/him) 10/16/2025 06:48 PM

Hey all, I'm planning to build a battery powered device, but it needs to stay connected to wifi and have low latency reconnects. I saw there is a light sleep which is availabe under power management. Any plan to support that [automatic light sleep](https://docs.espressif.com/projects/esp-idf/en/stable/esp32/api-reference/system/power_management.html) ?

#include "esp_pm.h"

// ... other includes and setup

void app_main(void) {
    esp_pm_config_esp32_t config = {
        .max_freq_mhz = 80, // or 160, depending on your needs
        .min_freq_mhz = 10, // minimum frequency for the clock
        .light_sleep_enable = true
    };
    esp_err_t result = esp_pm_configure(&config);

    if (result == ESP_OK) {
        // Configuration successful
    } else {
        // Handle error
    }
}

OPalex (he/him)

Hey all, I'm planning to build a battery powered device, but it needs to stay connected to wifi and have low latency reconnects. I saw there is a light sleep which is availabe unde...

floitsch 10/20/2025 12:03 PM

It already exists: https://libs.toit.io/esp32/library-summary#pm-configure(3%2C0%2C0%2Cenable-light-sleep%2Cmax-frequency-mhz%2Cmin-frequency-mhz)

However, I think that any battery-based device needs to bring the esp32 into deep-sleep. Light sleep doesn't save that much energy.

floitsch 10/20/2025 12:04 PM

Note that light-sleep might need a different sdkconfig (and thus a different envelope).

floitsch 10/20/2025 12:04 PM

If it does, please let me know, and I can maybe add such a configuration to our https://github.com/toitlang/envelopes

GitHub - toitlang/envelopes: Toit envelopes for different configura...

Toit envelopes for different configurations. Contribute to toitlang/envelopes development by creating an account on GitHub.

floitsch

It already exists: https://libs.toit.io/esp32/library-summary#pm-configure(3%2C0%2C0%2Cenable-light-sleep%2Cmax-frequency-mhz%2Cmin-frequency-mhz) However, I think that any batter...

alex (he/him) 10/26/2025 06:03 PM

Light sleep doesn't save that much energy.

According to sources on the internet, it should get down to 2-5 mA

OPalex (he/him)

Light sleep doesn't save that much energy. According to sources on the internet, it should get down to 2-5 mA

floitsch 10/26/2025 06:06 PM

I'm probably just wrong.
Please go ahead and test what is there. If you are missing things, let me know and I will try to help/fix it.

6 messages in total