IF Boot/Reset button

IF Boot/Reset button SW5 is connected to the interface MCU on the Development Kit (DK). It resets the nRF52833 System on Chip (SoC) or any device connected to the external programming connectors.

The button has two functions:

Resetting the nRF52833 SoC
Entering the bootloader mode of the interface MCU

During normal operation, the button functions as a reset button for the nRF52833 SoC. For this to work, pin reset on P0.18 must be enabled in embedded firmware.

The button is also used to enter the bootloader mode of the interface MCU. To enter the bootloader mode, keep the reset button pressed while powering up the DK until LED5 starts to blink. You can power up the DK by disconnecting and reconnecting the USB cable or by toggling the power switch (SW8).

Note: Pin reset can be enabled by adding the CONFIG_GPIO_AS_PINRESET variable to the compiler preprocessor macros. This depends on the Integrated Development Environment (IDE)/toolchain in use:

When using SEGGER Embedded Studio, go to Project > Edit Options > Code > Preprocessor > Preprocessor Definitions and add the CONFIG_GPIO_AS_PINRESET variable.
When using Keil, go to Project > Options for Target > C/C++ > Preprocessor Symbols > Define and add the CONFIG_GPIO_AS_PINRESET variable.

If your program does not enable pin reset, this functionality can also be enabled on a previously programmed device by calling nrfjprog.exe with argument --pinresetenable. To disable pin reset again, reprogram with --chiperase.