Sensor tri state GPIO

[repsejs]

Hi,

I am devolping a sensor system where I am in need of a Tri state GPIO solution

Currently using the NRF54l15DK with all the latest software versions (3.11, etc.), developing on Windows, where I have a variable resistor and need two distinct samples over the same part of the circuit: one sample has voltage across it, and the other doesn't.

The goal is to go between two states

state 1

p2.09 (Hi-Z) o---------|===|-----o----|===|-----------o p2.10 (Hi-Z)
                                  10k        |       r_var
                                     sample voltage

State 2
p2.09 (VDD High) o---------|===|-----o----|===|-----------o p2.10 (GND Low)
                                           10k        |       r_var
                                              sample voltage

I am wondering what the suitable GPIO configurations would be for this, since I want to be able to provide voltage and then effectively disconnect it from the GPIOs

Note: I have desoldered the transistor to the leds so that led-pwr is not interfering and no hardware components are affecting the pins

[Sigurd]

Hi!


You can use the nrf_gpio API for setting the pin state.

#include <hal/nrf_gpio.h>

nrf_gpio_cfg_output(#pin);

nrf_gpio_pin_set(#pin) / nrf_gpio_pin_clear(#pin)

-----

nrf_gpio_cfg_default(#pin) // To set a GPIO pin to its default state (high-impedance/tristate)