Using GPIO15 as GPIO OUTPUT in ESP32-WROOM

[ialonso]

Hello,

I have to use the GPIO15 of the ESP32-WROOM as output because it is connected with the enable signal of other component in a custom board.

I have it configured like this:

Code: Select all

/*********************************************
	 *************** DEFINES *********************
	 *********************************************/
	#define GPIO_LED_G              (14)
	#define GPIO_LED_Y              (02)
	#define GPIO_EN_UART       		(15)
	#define GPIO_OUTPUT_PIN_SEL  ((1ULL<<GPIO_LED_G) | (1ULL<<GPIO_LED_Y) | (1ULL<<GPIO_EN_UART))

Code: Select all

void gpio_init(void)
{
    gpio_reset_pin(GPIO_EN_UART);

    gpio_config_t io_conf;
    //disable interrupt
    io_conf.intr_type = GPIO_INTR_DISABLE;
    //set as output mode
    io_conf.mode = GPIO_MODE_OUTPUT;
    //bit mask of the pins that you want to set,e.g.GPIO18/19
    io_conf.pin_bit_mask = GPIO_OUTPUT_PIN_SEL;
    //disable pull-down mode
    io_conf.pull_down_en = 0;
    //disable pull-up mode
    io_conf.pull_up_en = 0;
    //configure GPIO with the given settings
    gpio_config(&io_conf);
}

The GPIO14, GPIO02 and others with I have made some tests work properly. But when I put the level of GPIO15 to high, I get the following signal:



I have tried to use the "gpio_reset_pin" function in order to reset the GPIO15 because I have read that is a strapping and JTAG GPIO, but it doesn't work.

How could I use it as normal output?

Thanks in advance

[ESP_Sprite]

That should just work. Are you sure there's not something else dragging the pin down? Perhaps using an oscilloscope rather than a LA may help identify the issue?