nRF52840 Dongle v1.0.0

Buttons and LEDs

The nRF528540 Dongle is equipped with a green LED (LD1), a multicolor RGB LED (LD2), a user configurable button (SW1), and a reset button (SW2).

The LEDs and buttons are connected to dedicated I/Os on the nRF52840 SoC.

Figure 1. nRF52840 Dongle buttons and LEDs
nRF52840 Dongle buttons and LEDs
Table 1. LED connections
Part Description GPIO
SW1 Button P1.06
SW2 Reset P0.181
LD1 Green P0.06
LD2 Red P0.08
LD2 Green P1.09
LD2 Blue P0.12

The buttons are active low, which means that the input will be connected to ground when the button is activated. The SW1 button has no external pull-up resistor, but the reset button (SW2) has a 10 k pull-up resistor. To use SW1, P1.06 must be configured as an input with an internal pull-up resistor.

The LEDs are active low, which means that writing a logical zero '0' to the output pin will illuminate the LED.

1 SW2 is also connected to P0.19, P0.21, P0.23, and P0.25. This is done to simplify PCB routing. These GPIOs should not be used and should be left as input with no pull or be disconnected by firmware.