RE: Pin 20 cannot pullup

StevenW807 — Tue, 28 Sep 2021 06:53:29 GMT

Problem solved.

Because I added my custom functions to the nRF52805 board (e.g. power ON/OFF button) from one of BLE example projects, which is built for nRF52832. Some buttons were configured by BLE functions by default.

Firstly, we need to change pca10040.h file. An example is:

// The code will save the following 2 buttons as an array
// So button0 in the array is pin 20
// and button1 in the array is pin 21

#define BUTTONS_NUMBER 2

#define BUTTON_START   20
#define BUTTON_1       20
#define BUTTON_1       21
#define BUTTON_STOP    21
#define BUTTON_PULL    NRF_GPIO_PIN_PULLUP

Then, we need to read the bsp_btn_ble.c file. Some LEDs and buttons were configured in BLE functions by default (e.g. connect, disconnect BLE buttons). If you would like to use the button for custom functions, you might need to modifty/delete the button functions in bsp_btn_ble.c. For example,

#define BTN_ID_WAKEUP             1  /**< ID of button used to wake up the application. */
#define BTN_ID_SLEEP              1  /**< ID of button used to put the application into sleep mode. */
#define BTN_ID_DISCONNECT         1  /**< ID of button used to gracefully terminate a connection on long press. */
#define BTN_ID_WAKEUP_BOND_DELETE 1  /**< ID of button used to wake up the application and delete all bonding information. */
#define BTN_ID_WHITELIST_OFF      1  /**< ID of button used to turn off usage of the whitelist. */

After doing the above 2 steps, my button pin is pulled to HIGH by default. The power ON/OFF button works well now.

Also, plz Remember to add a debouncing capacitor for your button on PCB as well.

RE: Pin 20 cannot pullup

ovrebekk — Thu, 02 Sep 2021 05:42:12 GMT

What if you just configure the pin through the nrf_gpio library, like this?

nrf_gpio_cfg_input(20, NRF_GPIO_PIN_PULLUP);

Will it still not be pulled up correctly?

Can you show me the rest of the code where you initialize the button library?

Best regards
Torbjørn

RE: Pin 20 cannot pullup

StevenW807 — Wed, 01 Sep 2021 05:48:50 GMT

Sorry for the confusion. Pin 21 actually connected with a button, NOT LED. I have fixed the wrong symbol image.

RE: Pin 20 cannot pullup

ovrebekk — Wed, 25 Aug 2021 13:27:16 GMT

It looks like P0.20 is connected to a LED in your schematic.

Why do you want to configure it as a button if it is connected to a LED?

Can you confirm if this is correct?

Best regards
Torbjørn