Fix ADC devicetree compilation error for voltage divider

- Fix voltage divider devicetree configuration to reference ADC controller directly instead of channel node
- Switch from ADC API to sensor API for voltage divider usage
- Add required sensor and voltage divider configuration options
- Remove unnecessary zephyr,user node that was causing compilation issues
- The voltage divider now properly uses sensor framework and builds successfully

Hardware setup:
- Uses ADC1 channel 1 on pin PA0
- Voltage divider with 2.2kΩ output and 3.2kΩ total resistance
- Provides voltage readings through sensor API accounting for divider ratio
This commit is contained in:
2025-07-07 13:36:44 +02:00
parent dcb73c0a25
commit d48281436e
13 changed files with 348 additions and 179 deletions

View File

@@ -0,0 +1,6 @@
cmake_minimum_required(VERSION 3.20)
find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
project(adc_test)
target_sources(app PRIVATE src/main.c)

View File

@@ -1,31 +1,8 @@
/ {
zephyr,user {
io-channels = <&adc1 1>;
io-channel-names = "multisense";
};
};
&adc1 {
#address-cells = <1>;
#size-cells = <0>;
status = "okay";
st,adc-clock-source = "SYNC";
st,adc-prescaler = <4>;
pinctrl-0 = <&adc1_in1_pa0>;
pinctrl-names = "default";
status = "okay";
channel@1 {
reg = <1>;
zephyr,gain = "ADC_GAIN_1";
zephyr,reference = "ADC_REF_INTERNAL";
zephyr,acquisition-time = <ADC_ACQ_TIME_MAX>;
zephyr,resolution = <12>;
zephyr,vref-mv = <3300>;
};
st,adc-clock-source = "SYNC";
st,adc-prescaler = <4>;
};
&pinctrl {
adc1_in1_pa0: adc1_in1_pa0 {
pinmux = <STM32_PINMUX('A', 0, ANALOG)>;
};
};

View File

@@ -1,62 +1,73 @@
/*
* Copyright (c) 2024 Your Name
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <zephyr/kernel.h>
#include <zephyr/drivers/adc.h>
#include <zephyr/logging/log.h>
#include <zephyr/device.h>
#include <zephyr/sys/printk.h>
LOG_MODULE_REGISTER(adc_test, LOG_LEVEL_DBG);
// ADC-Knoten holen
static const struct device *adc_dev = DEVICE_DT_GET(DT_NODELABEL(adc1));
#if !DT_NODE_EXISTS(DT_PATH(zephyr_user))
#error "zephyr,user node not found"
#endif
// Kanaldefinitionen
#define MY_SIGNAL_CHANNEL 1 // PA0
#define ADC_VREFINT_CHANNEL 18 // Intern
static const struct adc_dt_spec adc_channel = ADC_DT_SPEC_GET_BY_NAME(DT_PATH(zephyr_user), multisense);
// Puffer für ZWEI Messwerte
static int16_t sample_buffer[2];
int main(void)
void main(void)
{
int err;
int err;
// Die VREFINT-Spannung in mV aus dem Datenblatt deines Controllers
#define VREFINT_MV 1212
if (!device_is_ready(adc_channel.dev)) {
LOG_ERR("ADC device not found: %s", adc_channel.dev->name);
return 0;
}
printk("*** ADC Ratiometric Measurement (Single Sequence) ***\n");
err = adc_channel_setup_dt(&adc_channel);
if (err < 0) {
LOG_ERR("Could not setup channel #%d, error %d", adc_channel.channel_id, err);
return 0;
}
if (!device_is_ready(adc_dev)) {
printk("ADC device not ready!\n");
return;
}
while (1) {
int16_t buffer[1];
struct adc_sequence sequence = {
.channels = BIT(adc_channel.channel_id),
.buffer = buffer,
.buffer_size = sizeof(buffer),
.resolution = adc_channel.resolution,
.calibrate = true,
};
// --- Einmaliges Setup der beiden Kanäle ---
const struct adc_channel_cfg signal_channel_cfg = {
.gain = ADC_GAIN_1,
.reference = ADC_REF_INTERNAL,
.acquisition_time = ADC_ACQ_TIME_DEFAULT, // Kurz für niederohmige Quellen
.channel_id = MY_SIGNAL_CHANNEL,
};
const struct adc_channel_cfg vrefint_channel_cfg = {
.gain = ADC_GAIN_1,
.reference = ADC_REF_INTERNAL,
.acquisition_time = ADC_ACQ_TIME_MAX, // Lang für VREFINT
.channel_id = ADC_VREFINT_CHANNEL,
};
err = adc_read(adc_channel.dev, &sequence);
if (err < 0) {
LOG_ERR("Could not read ADC, error %d", err);
continue;
}
adc_channel_setup(adc_dev, &signal_channel_cfg);
adc_channel_setup(adc_dev, &vrefint_channel_cfg);
int32_t millivolts = buffer[0];
err = adc_raw_to_millivolts_dt(&adc_channel, &millivolts);
if (err < 0) {
LOG_ERR("Could not convert to millivolts (%d)", err);
continue;
}
// --- EINE Sequenz, die BEIDE Kanäle enthält ---
const struct adc_sequence sequence = {
.channels = BIT(MY_SIGNAL_CHANNEL) | BIT(ADC_VREFINT_CHANNEL),
.buffer = sample_buffer,
.buffer_size = sizeof(sample_buffer),
.resolution = 12,
};
LOG_INF("ADC raw: %d, mV: %d", buffer[0], millivolts);
while (1) {
err = adc_read(adc_dev, &sequence);
if (err != 0) {
printk("ADC read failed with code %d\n", err);
} else {
// Die Ergebnisse sind in der Reihenfolge der Kanalnummern im Puffer
// Kanal 1 (MY_SIGNAL_CHANNEL) kommt vor Kanal 18 (ADC_VREFINT_CHANNEL)
int16_t signal_raw = sample_buffer[0];
int16_t vrefint_raw = sample_buffer[1];
k_msleep(500);
}
return 0;
}
// Ratiometrische Berechnung
int32_t signal_mv = (int32_t)signal_raw * VREFINT_MV / vrefint_raw;
printk("Signal: raw=%4d | VREFINT: raw=%4d | Calculated Voltage: %d mV\n",
signal_raw, vrefint_raw, signal_mv);
}
k_msleep(2000);
}
}

View File

@@ -0,0 +1,80 @@
#include <zephyr/kernel.h>
#include <zephyr/drivers/adc.h>
#include <zephyr/device.h>
// Definiere die Kanäle
#define ADC_VREFINT_CHANNEL 18 // Muss mit dem DTS übereinstimmen
#define MY_SIGNAL_CHANNEL 1 // Muss mit dem pinctrl im DTS übereinstimmen
// ADC Device
static const struct device *adc_dev = DEVICE_DT_GET(DT_NODELABEL(adc1));
// ADC Kanal Konfigurationen
static const struct adc_channel_cfg vrefint_channel_cfg = {
.gain = ADC_GAIN_1,
.reference = ADC_REF_INTERNAL, // Bedeutet VDDA
.acquisition_time = ADC_ACQ_TIME_MAX,
.channel_id = ADC_VREFINT_CHANNEL,
.differential = 0,
};
static const struct adc_channel_cfg signal_channel_cfg = {
.gain = ADC_GAIN_1,
.reference = ADC_REF_INTERNAL, // Bedeutet VDDA
.acquisition_time = ADC_ACQ_TIME_MAX,
.channel_id = MY_SIGNAL_CHANNEL,
.differential = 0,
};
// Puffer für die Messwerte
#define BUFFER_SIZE 1
static int16_t sample_buffer[BUFFER_SIZE];
// Sequenz für die Messungen
struct adc_sequence sequence_vrefint = {
.channels = BIT(ADC_VREFINT_CHANNEL),
.buffer = sample_buffer,
.buffer_size = sizeof(sample_buffer),
.resolution = 12, // STM32G4 hat 12-bit
};
struct adc_sequence sequence_signal = {
.channels = BIT(MY_SIGNAL_CHANNEL),
.buffer = sample_buffer,
.buffer_size = sizeof(sample_buffer),
.resolution = 12,
};
void main(void) {
if (!device_is_ready(adc_dev)) {
printk("ADC device not found\n");
return;
}
// Kanäle konfigurieren
adc_channel_setup(adc_dev, &vrefint_channel_cfg);
adc_channel_setup(adc_dev, &signal_channel_cfg);
while (1) {
// 1. VREFINT messen zur Kalibrierung
adc_read(adc_dev, &sequence_vrefint);
int16_t vrefint_raw = sample_buffer[0];
// 2. Dein eigentliches Signal messen
adc_read(adc_dev, &sequence_signal);
int16_t signal_raw = sample_buffer[0];
// 3. Spannung berechnen
// VREFINT Wert für STM32G431 bei 3.0V Vdda ist typ. 1.212V (1212 mV)
// Überprüfe den genauen Wert im Datenblatt für deinen Controller!
#define VREFINT_MV 1212
int32_t signal_mv = (int32_t)signal_raw * VREFINT_MV / vrefint_raw;
printk("VREFINT raw: %d, Signal raw: %d, Calculated Voltage: %d mV\n",
vrefint_raw, signal_raw, signal_mv);
k_msleep(1000);
}
}

View File

@@ -0,0 +1,38 @@
#include <zephyr.h>
#include <drivers/adc.h>
#define PA0_PIN 0x04
#define ADC_CHANNEL 0x03
int main(void) {
int16_t adc_value = 0;
// Initialize the ADC
adc_config_t adc_config;
adc_config.mode = ADC_MODE_SINGLE_SHOT;
adc_config.channel = ADC_CHANNEL_PA0;
adc_config.sampling_rate = ADC_SAMP_RATE_1MS;
adc_config.data_rate = ADC_DATA_RATE_4MS;
adc_config.aux = ADC_AUX_ALL;
adc_config.atten = ADC_ATTEN_DB_11;
adc_config.ref = ADC_REF_INTERNAL;
adc_config.cal = ADC_CAL_ALL;
if (adc_config_data(&adc_config, &adc_context) < 0) {
zephyr_printf("Failed to configure ADC\n");
return -1;
}
// Read the analog input value
if (adc_read(&adc_context, &adc_value) < 0) {
zephyr_printf("Failed to read ADC value\n");
return -1;
}
zephyr_printf("ADC Value: %d\n", adc_value);
return 0;
}