Use Reset pin as a normal GPIO - nRF52832

RE: Use Reset pin as a normal GPIO - nRF52832

Simonr — Tue, 21 Jan 2025 09:29:04 GMT

I understand, but in your last reply you said that the reset pin now worked as a GPIO, but that there were some other issues with your device after flashing. Do you also see these issues after a power cycle of the board when flashing? What exactly is the issue you're currently facing on your end?

Best regards,

Simon

RE: Use Reset pin as a normal GPIO - nRF52832

bhargav_gondaliya — Mon, 20 Jan 2025 14:14:44 GMT

Simonr , I want to use reset pin as normal gpio. when I press single time it should be hard reset by calling NVIC_SystemReset(); and when pressed for >=10 sec it should be hard reset and erase an eeprom ( I have external eeprom in my custom nrf52832 board.

case if(pins & BIT(button_0.pin)){  // detect p0.21
        printk("button 0 pressed");
        LOG_INF("reset pressed\n\r");
        read_time(rtc_dev,(time_t *)&unix_time);   // read time from mcp7940
        uint32_t reset_pressed_epoch_time = unix_time;
        while (!gpio_pin_get_dt(&button_0) && (unix_time - reset_pressed_epoch_time) <= 10) //if time <10 sec while loop wii execute 
        {
            k_msleep(100);
            read_time(rtc_dev,(time_t *)&unix_time);
        }
        if (unix_time - reset_pressed_epoch_time > 10)  // if time >10 this condition will be true
        {
            Reset_Flag=1;
            eeprom_write(i2c_dev,EEPROM_RESET_FLAG_ADDRESS, &Reset_Flag, 1); // write reset flag value in eeprom
            eeprom_write(i2c_dev,EEPROM_RESET_TIME_FLAG, &current_epoch_time, 4); // write reset time in eeprom 
            guide_flag=1;
            eeprom_write(i2c_dev,EEPROM_DEVICE_GUIDE_ADDRESS,&guide_flag,1);
            reset_hardware_locally();  // erase some portion of eeprom
            //reset_hardware();
            k_msleep(1000);
            NVIC_SystemReset();  // hard reset
        }
        else
        {
            k_msleep(1000);
            NVIC_SystemReset(); // if button pressed <10 sec else statement will execute
        }
        break;

RE: Use Reset pin as a normal GPIO - nRF52832

Simonr — Mon, 20 Jan 2025 12:46:39 GMT

Yes, it should be fine setting it up like this. You need to use the /delete-property/ if the gpio-as-nreset is set by default I believe. But why are you enabling the Softreset when flashing after doing so? The pin shouldn't be needed to do a full reset when flashing? Have you tried power cycling the board and see if it works afterwards when you've flashed it like this? A full power cycle might be needed after flashing the device when using softreset.

What exactly are you using the reset pin GPIO for in your project?

Best regards,

Simon

RE: Use Reset pin as a normal GPIO - nRF52832

bhargav_gondaliya — Fri, 17 Jan 2025 11:18:49 GMT

Hi Simonr

I am using a nRF Connect SDK v2.6.0. I have tried that solution did not worked.

currently I have deleted gpio-as-nreset; property like as below.

&uicr {
    /delete-property/gpio-as-nreset;
};

is it validate according to the format?

also I added a line in setting.json file.

In vscode file/preferences/setting/"nrf-connect.flash.softreset": true (enabled from setting)

after that I able to use reset pin as gpio. but it is correct solution to use reset pin as gpio?? after that I am not able to connect a device via ble, not updating display etc..

because I want to implement single press and long press functionality on that pin.
below is my code for long press and single press

case if(pins & BIT(button_0.pin)){
        printk("button 0 pressed");
        LOG_INF("reset pressed\n\r");
        read_time(rtc_dev,(time_t *)&unix_time);
        uint32_t reset_pressed_epoch_time = unix_time;
        while (!gpio_pin_get_dt(&button_0) && (unix_time - reset_pressed_epoch_time) <= 10)
        {
            k_msleep(100);
            read_time(rtc_dev,(time_t *)&unix_time);
        }
        if (unix_time - reset_pressed_epoch_time > 10)
        {
            Reset_Flag=1;
            eeprom_write(i2c_dev,EEPROM_RESET_FLAG_ADDRESS, &Reset_Flag, 1);
            eeprom_write(i2c_dev,EEPROM_RESET_TIME_FLAG, &current_epoch_time, 4);
            guide_flag=1;
            eeprom_write(i2c_dev,EEPROM_DEVICE_GUIDE_ADDRESS,&guide_flag,1);
            reset_hardware_locally();
            //reset_hardware();
            k_msleep(1000);
            NVIC_SystemReset();
        }
        else
        {
            k_msleep(1000);
            NVIC_SystemReset();
        }
        break;

RE: Use Reset pin as a normal GPIO - nRF52832

Simonr — Fri, 17 Jan 2025 10:33:44 GMT

What version of the nRF Connect SDK are you using? In the latest versions (at least from NCS 2.7.0 and newer) the correct way to set the reset pin as a GPIO is through the devicetree. By default, the board's devicetree sets the GPIO as a reset with the following. Removing this line from the .dts file should make the reset pin function as a GPIO. This is documented in the Zephyr 3.5 migration guide: https://docs.nordicsemi.com/bundle/ncs-latest/page/zephyr/releases/migration-guide-3.5.html

&uicr {

gpio-as-nreset;

};

Best regards,

Simon

RE: Use Reset pin as a normal GPIO - nRF52832

bhargav_gondaliya — Fri, 17 Jan 2025 05:25:09 GMT

Thanks X4ce , how can I implement that solution in my application?
currently my setting.json looks like as below.

{
    "nrf-connect.taskBindings": {
        "pristineBuild": [
            {
                "taskName": "Build: long_press_v2/build (active)",
                "buildConfigs": [
                    "${workspaceFolder}/build"
                ]
            }
        ]
    }
}

RE: Use Reset pin as a normal GPIO - nRF52832

X4ce — Thu, 16 Jan 2025 13:44:31 GMT

Hi,

This might be helpful for you.

https://devzone.nordicsemi.com/f/nordic-q-a/100486/reset-pin-as-gpio/429399

Regards