88 lines
2.3 KiB
Plaintext
88 lines
2.3 KiB
Plaintext
/* Pro Micro nRF52840 (nice!nano v2 compatible) + Adafruit SHT41 on a gated supply */
|
|
#include <zephyr/dt-bindings/adc/adc.h>
|
|
#include <zephyr/dt-bindings/adc/nrf-saadc.h>
|
|
#include <zephyr/dt-bindings/gpio/nordic-nrf-gpio.h>
|
|
|
|
/ {
|
|
/* P0.17 powers the SHT41: switched on only while the sensor is in use */
|
|
sens_pwr: sensor-power {
|
|
compatible = "power-domain-gpio";
|
|
enable-gpios = <&gpio0 17 (GPIO_ACTIVE_HIGH | NRF_GPIO_DRIVE_H0H1)>;
|
|
startup-delay-us = <3000>; /* SHT41 power-up + breakout caps */
|
|
#power-domain-cells = <0>;
|
|
zephyr,pm-device-runtime-auto;
|
|
};
|
|
|
|
zephyr,user {
|
|
io-channels = <&adc 0>;
|
|
};
|
|
};
|
|
|
|
/* DC/DC on REG0 (VDDH -> VDD) and REG1 (VDD -> core) */
|
|
®0 {
|
|
status = "okay";
|
|
};
|
|
|
|
®1 {
|
|
regulator-initial-mode = <NRF5X_REG_MODE_DCDC>;
|
|
};
|
|
|
|
/* I2C: SDA P0.20, SCL P0.22. "sleep" state = pins disconnected (no back-feeding) */
|
|
&pinctrl {
|
|
sht_i2c_default: sht_i2c_default {
|
|
group1 {
|
|
psels = <NRF_PSEL(TWIM_SDA, 0, 20)>, <NRF_PSEL(TWIM_SCL, 0, 22)>;
|
|
bias-pull-up;
|
|
};
|
|
};
|
|
|
|
sht_i2c_sleep: sht_i2c_sleep {
|
|
group1 {
|
|
psels = <NRF_PSEL(TWIM_SDA, 0, 20)>, <NRF_PSEL(TWIM_SCL, 0, 22)>;
|
|
low-power-enable;
|
|
};
|
|
};
|
|
};
|
|
|
|
&i2c0 {
|
|
compatible = "nordic,nrf-twim";
|
|
status = "okay";
|
|
clock-frequency = <I2C_BITRATE_FAST>;
|
|
pinctrl-0 = <&sht_i2c_default>;
|
|
pinctrl-1 = <&sht_i2c_sleep>;
|
|
pinctrl-names = "default", "sleep";
|
|
zephyr,pm-device-runtime-auto; /* bus enabled only during transfers */
|
|
|
|
sht41: sht4x@44 {
|
|
compatible = "sensirion,sht4x";
|
|
reg = <0x44>;
|
|
repeatability = <2>; /* high precision, no heater */
|
|
power-domains = <&sens_pwr>;
|
|
zephyr,pm-device-runtime-auto;
|
|
};
|
|
};
|
|
|
|
/* Battery: VDDH/5, internal 0.6 V ref, gain 1/2 -> 0..1.2 V range */
|
|
&adc {
|
|
#address-cells = <1>;
|
|
#size-cells = <0>;
|
|
status = "okay";
|
|
|
|
channel@0 {
|
|
reg = <0>;
|
|
zephyr,gain = "ADC_GAIN_1_2";
|
|
zephyr,reference = "ADC_REF_INTERNAL";
|
|
zephyr,acquisition-time = <ADC_ACQ_TIME(ADC_ACQ_TIME_MICROSECONDS, 10)>;
|
|
zephyr,input-positive = <NRF_SAADC_VDDHDIV5>;
|
|
zephyr,resolution = <14>; /* LSB = 6000 mV / 16384 = 0.37 mV at VDDH */
|
|
zephyr,oversampling = <3>; /* 2^3 = 8x */
|
|
};
|
|
};
|
|
|
|
/* Unused board peripherals */
|
|
&i2c1 { status = "disabled"; };
|
|
&spi2 { status = "disabled"; };
|
|
&pwm0 { status = "disabled"; };
|
|
&uart0 { status = "disabled"; };
|
|
&usbd { status = "disabled"; };
|