ESP32 confusing interrupt behavior

[Bilal_azhar]

Hi! The hardware I am using is an esp32-cam AI thinker board and a SR602 PIR motion sensorhttps://www.sinoning.com/hc-sr602-datasheet/. The output pin is connected to the ground with a 10K resistor

My objective is to wake up the esp32 from deep sleep whenever the sensor output voltage drops from 3.3v to 0. I have tested my setup the sensor works properly it outputs 3,3v across the 10k resistor when I move my hand over it and the esp32 wake-ups when I connect GPIO 13 to the ground (esp32 wakes up).

The problem I am facing is that when I connect my sensor output to GPIO 13 things don't make sense, from what I understand the device should only wake up when the sensor changes voltage from 3,3 to GND. This doesn't seem to be the case the esp32 keeps waking up randomly in 1-2 seconds after the deep_sleep start function is called. I thought maybe something is wrong with the sensor so I connected the GPIO 13 straight to GND and that shouldn't trigger the wake interrupt right? But I am seeing the same behaviour. Can anyone help figure out what's wrong?

Code: Untitled.c Select all

#define MOTION_WAKEUP_PIN 13



void gpio_init(gpio_int_type_t INTR_MODE, gpio_mode_t PIN_MODE , gpio_pull_mode_t UP_MODE , gpio_pull_mode_t DOWN_MODE, u_int32_t PIN)

{

    gpio_config_t io_config;

    io_config.intr_type = INTR_MODE;

    io_config.mode = PIN_MODE;

    io_config.pull_up_en = UP_MODE;

    io_config.pull_down_en = DOWN_MODE;

    io_config.pin_bit_mask = 1ULL << PIN;

    gpio_config(&io_config);

}



void app_main(void)

{

    //Initialize NVS

    esp_err_t ret = nvs_flash_init();

    if (ret == ESP_ERR_NVS_NO_FREE_PAGES || ret == ESP_ERR_NVS_NEW_VERSION_FOUND) {

      ESP_ERROR_CHECK(nvs_flash_erase());

      ret = nvs_flash_init();

    }

    ESP_ERROR_CHECK(ret);



    ESP_LOGI(wifi_TAG, "ESP_WIFI_MODE_STA");

    wifi_init_sta();



    gpio_init(GPIO_INTR_NEGEDGE,GPIO_MODE_INPUT,GPIO_PULLUP_ENABLE,GPIO_PULLDOWN_DISABLE,MOTION_WAKEUP_PIN);



    while(1){



        vTaskDelay(5000 / portTICK_RATE_MS);

        esp_deep_sleep_start();



    }



}

[Sprite]

Hard to say. Do you have an oscilloscope so you can look at the signals the PIR sensor outputs? Perhaps it somehow has spikes that confuse the wakeup mechanism.

[MicroController]

You don't seem to have set up/enabled any wake-up source.