ESP32 Forum

AndrewM wrote: ↑

Thu Sep 19, 2019 9:02 pm

Hi,

I have GPIO17 set as an input interrupt pin with pullup/down disabled, and I'm using an external pullup resistor. This is connected to an optosiolator (LTV-844). I'm feeding the optoisolater a 60Hz test signal, so I should be getting interrupts at 120Hz.

However, the interrupt seems to only run once.

What am I doing wrong here?

Code: Select all

    uint64_t inmask = (1ULL << 17);
    gpio_config_t input_conf;
    input_conf.pin_bit_mask = inmask;
    input_conf.mode = GPIO_MODE_INPUT;
    input_conf.pull_up_en = 0; //disable pullup
    input_conf.pull_down_en = 0; //disable pulldown
    input_conf.intr_type = 0; //disable interrupts
    gpio_config(&input_conf);
    
    gpio_install_isr_service(ESP_INTR_FLAG_EDGE | ESP_INTR_FLAG_IRAM);
    gpio_isr_handler_add(17, input_isr_handler, NULL);
    gpio_set_intr_type(17, GPIO_INTR_NEGEDGE);
    gpio_intr_enable(17);

Code: Select all

    bool testflag = false;
    
static void IRAM_ATTR input_isr_handler(void* arg) {
	current_input_low = gpio_input_get();
    	current_input_high = gpio_input_get_high();
    	if(testflag) {
        	GPIO.enable_w1ts = 23;
        	testflag = false;
    	} else {
        	GPIO.enable_w1tc = 23;
        	testflag = true;
    	}
    	ets_printf("\nInterrupt\n");
}

I've checked that I am getting a good 120Hz signal on the pin (see: https://i.imgur.com/9EB3Bb8.png)