Implement real ADC readings with VND7050AJ sensor multiplexing

- Switch from simulated to real ADC readings in adc_sensor library
- Add GPIO control for VND7050AJ sensor selection (sen, s0, s1 pins)
- Implement proper ADC device and channel setup for voltage/current measurements
- Enable ADC driver in prj.conf (CONFIG_ADC=y)
- Disable simulation mode (CONFIG_ADC_SENSOR_SIMULATED=n)
- Add devicetree bindings for custom supply voltage and motor current sensors
- Update overlay with adc_sensors nodes using PB4, PB5, PB6 pins
- Integrate real ADC readings into Modbus server registers
- Support HSE/HSI clock source toggling in overlay configuration

setup-format-hook.sh

@@ -0,0 +1,56 @@
+#!/bin/sh
+
+# This script sets up a Git pre-commit hook to automatically format C/C++ files
+# in the 'software/' subdirectory using clang-format.
+
+# Define the path for the pre-commit hook
+HOOK_DIR=".git/hooks"
+HOOK_FILE="$HOOK_DIR/pre-commit"
+
+# Create the hooks directory if it doesn't exist
+mkdir -p "$HOOK_DIR"
+
+# Create the pre-commit hook script using a 'here document'
+cat > "$HOOK_FILE" << 'EOF'
+#!/bin/sh
+
+# --- Pre-commit hook for clang-format ---
+#
+# This hook formats staged C, C++, and Objective-C files in the 'software/'
+# subdirectory before a commit is made.
+# It automatically finds the .clang-format file in the software/ directory.
+#
+
+# Directory to be formatted
+TARGET_DIR="software/"
+
+# Use git diff to find staged files that are Added (A), Copied (C), or Modified (M).
+# We filter for files only within the TARGET_DIR.
+# The grep regex matches common C/C++ and Objective-C file extensions.
+FILES_TO_FORMAT=$(git diff --cached --name-only --diff-filter=ACM "$TARGET_DIR" | grep -E '\.(c|h|cpp|hpp|cxx|hxx|cc|hh|m|mm)$')
+
+if [ -z "$FILES_TO_FORMAT" ]; then
+    # No relevant files to format, exit successfully.
+    exit 0
+fi
+
+echo "› Running clang-format on staged files in '$TARGET_DIR'..."
+
+# Run clang-format in-place on the identified files.
+# clang-format will automatically find the .clang-format file in the software/ directory
+# or any of its parent directories.
+echo "$FILES_TO_FORMAT" | xargs clang-format -i
+
+# Since clang-format may have changed the files, we need to re-stage them.
+echo "$FILES_TO_FORMAT" | xargs git add
+
+echo "› Formatting complete."
+
+exit 0
+EOF
+
+# Make the hook executable
+chmod +x "$HOOK_FILE"
+
+echo "✅ Git pre-commit hook has been set up successfully."
+echo "   It will now automatically format files in the '$PWD/software' directory before each commit."

software/.clang-format

@@ -0,0 +1,5 @@
+# .clang-format
+BasedOnStyle: Google
+#IndentWidth: 4
+#ColumnLimit: 100
+#AllowShortFunctionsOnASingleLine: None

software/.vscode/settings.json

@@ -1,12 +1,15 @@
 {
 	// Hush CMake
 	"cmake.configureOnOpen": false,
-
 	// IntelliSense
 	"C_Cpp.default.compilerPath": "${userHome}/zephyr-sdk-0.17.1/arm-zephyr-eabi/bin/arm-zephyr-eabi-gcc.exe",
 	"C_Cpp.default.compileCommands": "${workspaceFolder}/build/compile_commands.json",
-
 	// File Associations
 	"files.associations": {
-		}
+		"app_version.h": "c"
+	},
+	"C_Cpp.clang_format_style": "file",
+	"nrf-connect.applications": [
+		"${workspaceFolder}/apps/slave_node"
+	],
 }

software/.vscode/tasks.json

@@ -2,31 +2,19 @@
 	"version": "2.0.0",
 	"tasks": [
 		{
-			"label": "West Build",
+            "label": "Format All C/C++ Files",
             "type": "shell",
+            "command": "find . -name \"*.c\" -o -name \"*.h\" | xargs clang-format -i",
+            "problemMatcher": [],
             "group": {
                 "kind": "build",
                 "isDefault": true
             },
-			"linux": {
-				"command": "${userHome}/zephyrproject/.venv/bin/west"
-			},
-			"windows": {
-				"command": "${userHome}/zephyrproject/.venv/Scripts/west.exe"
-			},
-			"osx": {
-				"command": "${userHome}/zephyrproject/.venv/bin/west"
-			},
-			"args": [
-				"build",
-				"-p",
-				"auto",
-				"-b",
-				"valve_node"
-			],
-			"problemMatcher": [
-				"$gcc"
-			]
+            "presentation": {
+                "reveal": "silent",
+                "clear": true,
+                "panel": "shared"
+            }
         },
 		{
 			"label": "West Configurable Build",

software/apps/gateway/src/main.c

@@ -6,8 +6,7 @@
 
 #include <zephyr/kernel.h>
 
-int main(void)
-{
+int main(void) {
   printk("Hello from Gateway!\n");
   return 0;
 }

software/apps/slave_node/.vscode/c_cpp_properties.json

@@ -0,0 +1,12 @@
+{
+    "configurations": [
+        {
+            "name": "Linux",
+            "compileCommands": "${workspaceFolder}/build/compile_commands.json",
+            "cStandard": "c99",
+            "cppStandard": "gnu++17",
+            "intelliSenseMode": "linux-gcc-arm"
+        }
+    ],
+    "version": 4
+}

software/apps/slave_node/VERSION

@@ -0,0 +1,5 @@
+VERSION_MAJOR = 0
+VERSION_MINOR = 0
+PATCHLEVEL = 1
+VERSION_TWEAK = 1
+EXTRAVERSION = devel

software/apps/slave_node/boards/weact_stm32g431_core.overlay

@@ -11,8 +11,63 @@
         s0-gpios = <&gpiob 6 GPIO_ACTIVE_HIGH>;  // S0 (PB6) - Status/Select 0 output from VND7050AJ
         s1-gpios = <&gpiob 5 GPIO_ACTIVE_HIGH>;  // S1 (PB5) - Status/Select 1 output from VND7050AJ
     };
+
+    adc_sensors {
+        compatible = "adc-sensors";
+        
+        supply_voltage: supply-voltage {
+            compatible = "custom,supply-voltage";
+            io-channels = <&adc1 1>;  /* ADC1 channel 1 (PA0) */
+            io-channel-names = "voltage";
+            reference-mv = <3300>;
+            voltage-divider-ratio = <4>;  /* Adjust based on your voltage divider */
+            
+            /* GPIO control pins using VND7050AJ pins */
+            sen-gpios = <&gpiob 4 GPIO_ACTIVE_HIGH>;  /* SEN (PB4) - enable sensor */
+            s0-gpios = <&gpiob 6 GPIO_ACTIVE_HIGH>;   /* S0 (PB6) - mux select bit 0 */
+            s1-gpios = <&gpiob 5 GPIO_ACTIVE_HIGH>;   /* S1 (PB5) - mux select bit 1 */
+            
+            measurement-delay-ms = <5>;  /* 5ms delay after GPIO setup */
         };
         
+        motor_current: motor-current {
+            compatible = "custom,motor-current";
+            io-channels = <&adc1 1>;  /* Same ADC channel, different mux setting */
+            io-channel-names = "current";
+            reference-mv = <3300>;
+            current-sense-resistor-mohm = <100>;  /* 100mΩ sense resistor */
+            
+            /* GPIO control pins using VND7050AJ pins */
+            sen-gpios = <&gpiob 4 GPIO_ACTIVE_HIGH>;  /* SEN (PB4) - enable sensor */
+            s0-gpios = <&gpiob 6 GPIO_ACTIVE_HIGH>;   /* S0 (PB6) - mux select bit 0 */
+            s1-gpios = <&gpiob 5 GPIO_ACTIVE_HIGH>;   /* S1 (PB5) - mux select bit 1 */
+            
+            measurement-delay-ms = <10>; /* 10ms delay for current settling */
+        };
+    };
+};
+
+// Clock configuration: Uncomment the following section to use calibrated HSI instead of HSE
+//&clk_hse {
+//    status = "disabled";  // Disable external crystal oscillator
+//};
+//
+//&clk_hsi {
+//    status = "okay";      // Enable internal high-speed oscillator (16 MHz, calibrated)
+//};
+//
+//&pll {
+//    // Change PLL source from HSE to HSI
+//    clocks = <&clk_hsi>;
+//    // Adjust multipliers to maintain 144 MHz system clock with 16 MHz HSI input
+//    // HSI = 16 MHz, div-m = 4, mul-n = 72, div-r = 2
+//    // PLL_VCO = (16 MHz / 4) * 72 = 288 MHz  
+//    // SYSCLK = 288 MHz / 2 = 144 MHz
+//    div-m = <4>;    // Divide HSI by 4 (16 MHz / 4 = 4 MHz)
+//    mul-n = <72>;   // Multiply by 72 (4 MHz * 72 = 288 MHz)
+//    div-r = <2>;    // Divide by 2 for system clock (288 MHz / 2 = 144 MHz)
+//};
+
 &usart1 {
 	modbus0 {
 		compatible = "zephyr,modbus-serial";

software/apps/slave_node/dts/bindings/adc/custom,motor-current.yaml

@@ -0,0 +1,48 @@
+description: Custom motor current measurement with GPIO control
+
+compatible: "custom,motor-current"
+
+properties:
+  io-channels:
+    type: phandle-array
+    required: true
+    description: ADC channel for current measurement
+
+  io-channel-names:
+    type: string-array
+    description: Names for the ADC channels
+
+  current-sense-resistor-mohm:
+    type: int
+    required: true
+    description: Current sense resistor value in milliohms
+
+  amplifier-gain:
+    type: int
+    default: 1
+    description: Current sense amplifier gain
+
+  reference-mv:
+    type: int
+    default: 3300
+    description: ADC reference voltage in millivolts
+
+  sen-gpios:
+    type: phandle-array
+    required: true
+    description: GPIO to enable/disable the current measurement sensor
+
+  s0-gpios:
+    type: phandle-array
+    required: true
+    description: GPIO for multiplexer control bit 0
+
+  s1-gpios:
+    type: phandle-array
+    required: true
+    description: GPIO for multiplexer control bit 1
+
+  measurement-delay-ms:
+    type: int
+    default: 10
+    description: Delay in milliseconds after setting GPIOs before ADC measurement

software/apps/slave_node/dts/bindings/adc/custom,supply-voltage.yaml

@@ -0,0 +1,63 @@
+description: Custom supply voltage measurement with GPIO control
+
+compatible: "custom,supply-voltage"
+
+properties:
+  io-channels:
+    type: phandle-array
+    required: true
+    description: ADC channel for voltage measurement
+
+  io-channel-names:
+    type: string-array
+    description: Names for the ADC channels
+
+  voltage-divider-ratio:
+    type: int
+    required: true
+    description: Voltage divider ratio for scaling
+
+  reference-mv:
+    type: int
+    default: 3300
+    description: ADC reference voltage in millivolts
+
+  sen-gpios:
+    type: phandle-array
+    required: true
+    description: GPIO to enable/disable the voltage measurement sensor
+
+  s0-gpios:
+    type: phandle-array
+    required: true
+    description: GPIO for multiplexer control bit 0
+
+  s1-gpios:
+    type: phandle-array
+    required: true
+    description: GPIO for multiplexer control bit 1
+
+  measurement-delay-ms:
+    type: int
+    default: 10
+    description: Delay in milliseconds after setting GPIOs before ADC measurement
+
+  sen-gpios:
+    type: phandle-array
+    required: true
+    description: GPIO for SEN (Sense Enable) pin
+
+  s0-gpios:
+    type: phandle-array
+    required: true
+    description: GPIO for S0 (Select 0) pin
+
+  s1-gpios:
+    type: phandle-array
+    required: true
+    description: GPIO for S1 (Select 1) pin
+
+  measurement-delay-ms:
+    type: int
+    default: 10
+    description: Delay in milliseconds after setting control pins before ADC reading

software/apps/slave_node/prj.conf

@@ -13,7 +13,6 @@ CONFIG_NVS=y
 CONFIG_FLASH=y
 CONFIG_FLASH_MAP=y
 CONFIG_FLASH_PAGE_LAYOUT=y
-CONFIG_SETTINGS_LOG_LEVEL_DBG=y
 
 # Config modbus
 CONFIG_UART_INTERRUPT_DRIVEN=y
@@ -21,3 +20,7 @@ CONFIG_MODBUS=y
 CONFIG_MODBUS_ROLE_SERVER=y
 CONFIG_MODBUS_BUFFER_SIZE=256
 
+# ADC Sensor Configuration - Use real ADC readings
+CONFIG_ADC_SENSOR_SIMULATED=n
+CONFIG_ADC=y
+

software/apps/slave_node/src/main.c

@@ -1,15 +1,17 @@
-#include <zephyr/kernel.h>
-#include <zephyr/settings/settings.h>
-#include <zephyr/logging/log.h>
+#include <app_version.h>
+#include <lib/fwu.h>
 #include <lib/modbus_server.h>
 #include <lib/valve.h>
-#include <lib/fwu.h>
+#include <zephyr/kernel.h>
+#include <zephyr/logging/log.h>
+#include <zephyr/settings/settings.h>
 
 LOG_MODULE_REGISTER(main, LOG_LEVEL_INF);
 
-int main(void)
-{
-	LOG_INF("Starting Irrigation System Slave Node");
+int main(void) {
+  int rc;
+  LOG_INF("Starting Irrigation System Slave Node version %s (Build version %s)",
+          APP_VERSION_STRING, STRINGIFY(APP_BUILD_VERSION));
 
   if (settings_subsys_init() || settings_load()) {
     LOG_ERR("Settings initialization or loading failed");
@@ -18,8 +20,9 @@ int main(void)
   valve_init();
   fwu_init();
 
-	if (modbus_server_init()) {
-		LOG_ERR("Modbus RTU server initialization failed");
+  rc = modbus_server_init();
+  if (rc < 0) {
+    LOG_ERR("Modbus RTU server initialization failed: %d", rc);
     return 0;
   }
 

software/include/lib/adc_sensor.h

@@ -0,0 +1,46 @@
+#ifndef ADC_SENSOR_H
+#define ADC_SENSOR_H
+
+#include <stdint.h>
+
+/**
+ * @file adc_sensor.h
+ * @brief API for the ADC sensor library.
+ *
+ * This library provides functions to initialize and read from the ADC sensors,
+ * specifically for measuring supply voltage and motor current.
+ * It can operate in a real or simulated mode.
+ */
+
+/**
+ * @brief Initializes the ADC sensor system.
+ *
+ * This function sets up the necessary ADC channels and configurations.
+ * It should be called once before any other function in this library.
+ * In simulated mode, it logs the simulated values.
+ *
+ * @return 0 on success, or a negative error code on failure.
+ */
+int adc_sensor_init(void);
+
+/**
+ * @brief Gets the current supply voltage reading.
+ *
+ * This function reads the value from the corresponding ADC channel and converts
+ * it to millivolts.
+ *
+ * @return The supply voltage in millivolts (mV).
+ */
+uint16_t adc_sensor_get_voltage_mv(void);
+
+/**
+ * @brief Gets the current motor current reading.
+ *
+ * This function reads the value from the motor driver's sense pin via ADC
+ * and converts it to milliamps. This is used for end-stop detection.
+ *
+ * @return The motor current in milliamps (mA).
+ */
+uint16_t adc_sensor_get_current_ma(void);
+
+#endif /* ADC_SENSOR_H */

software/include/lib/fwu.h

@@ -3,8 +3,45 @@
 
 #include <stdint.h>
 
+/**
+ * @file fwu.h
+ * @brief API for the Firmware Update (FWU) library.
+ *
+ * This library provides the core logic for handling the over-the-air firmware
+ * update process via Modbus. It manages the data buffer, processes commands,
+ * and calculates CRC checksums for data verification.
+ */
+
+/**
+ * @brief Initializes the firmware update module.
+ *
+ * This function currently does nothing but is a placeholder for future
+ * initialization logic.
+ */
 void fwu_init(void);
+
+/**
+ * @brief Handles incoming Modbus register writes related to firmware updates.
+ *
+ * This function is the main entry point for the FWU process. It parses the
+ * address and value from a Modbus write operation and takes appropriate action,
+ * such as storing metadata (offset, size) or data chunks, and processing
+ * commands (verify, finalize).
+ *
+ * @param addr The Modbus register address being written to.
+ * @param reg The 16-bit value being written to the register.
+ */
 void fwu_handler(uint16_t addr, uint16_t reg);
+
+/**
+ * @brief Gets the CRC16-CCITT of the last received firmware chunk.
+ *
+ * After a data chunk is fully received into the buffer, this function can be
+ * called to retrieve the calculated CRC checksum. The master can then compare
+ * this with its own calculated CRC to verify data integrity.
+ *
+ * @return The 16-bit CRC of the last chunk.
+ */
 uint16_t fwu_get_last_chunk_crc(void);
 
 #endif  // FWU_H

software/include/lib/modbus_server.h

@@ -4,51 +4,161 @@
 #include <stdint.h>
 
 /**
- * @brief Modbus Input Register Addresses.
+ * @file modbus_server.h
+ * @brief API for the Modbus server implementation.
+ *
+ * This file defines the Modbus register map and provides functions to
+ * initialize and manage the Modbus server.
+ */
+
+/**
+ * @brief Modbus Input Register Addresses (Read-Only).
+ * @see docs/modbus-registers.de.md
+ */
+enum {
+  /**
+   * @brief Kombiniertes Status-Register für das Ventil.
+   * High-Byte: Bewegung (0=Idle, 1=Öffnet, 2=Schliesst, 3=Fehler).
+   * Low-Byte: Zustand (0=Geschlossen, 1=Geöffnet).
    */
-enum
-{
-	/* Valve Control & Status */
   REG_INPUT_VALVE_STATE_MOVEMENT = 0x0000,
+  /**
+   * @brief Aktueller Motorstrom in Milliampere (mA).
+   */
   REG_INPUT_MOTOR_CURRENT_MA = 0x0001,
-	/* Digital Inputs */
+  /**
+   * @brief Bitmaske der digitalen Eingänge. Bit 0: Eingang 1, Bit 1: Eingang 2.
+   * 1=Aktiv.
+   */
   REG_INPUT_DIGITAL_INPUTS_STATE = 0x0020,
+  /**
+   * @brief Event-Flags für Taster (Clear-on-Read). Bit 0: Taster 1 gedrückt.
+   * Bit 1: Taster 2 gedrückt.
+   */
   REG_INPUT_BUTTON_EVENTS = 0x0021,
-	/* System Config & Status */
+  /**
+   * @brief Firmware-Version, z.B. 0x0102 für v1.2.
+   */
   REG_INPUT_FIRMWARE_VERSION_MAJOR_MINOR = 0x00F0,
+  /**
+   * @brief Firmware-Version Patch-Level, z.B. 3 für v1.2.3.
+   */
   REG_INPUT_FIRMWARE_VERSION_PATCH = 0x00F1,
+  /**
+   * @brief Gerätestatus (0=OK, 1=Allgemeiner Fehler).
+   */
   REG_INPUT_DEVICE_STATUS = 0x00F2,
+  /**
+   * @brief Untere 16 Bit der Uptime in Sekunden.
+   */
   REG_INPUT_UPTIME_SECONDS_LOW = 0x00F3,
+  /**
+   * @brief Obere 16 Bit der Uptime in Sekunden.
+   */
   REG_INPUT_UPTIME_SECONDS_HIGH = 0x00F4,
+  /**
+   * @brief Aktuelle Versorgungsspannung in Millivolt (mV).
+   */
   REG_INPUT_SUPPLY_VOLTAGE_MV = 0x00F5,
+  /**
+   * @brief CRC16 des zuletzt im Puffer empfangenen Daten-Chunks für das
+   * Firmware-Update.
+   */
   REG_INPUT_FWU_LAST_CHUNK_CRC = 0x0100
 };
 
 /**
- * @brief Modbus Holding Register Addresses.
+ * @brief Modbus Holding Register Addresses (Read/Write).
+ * @see docs/modbus-registers.de.md
+ */
+enum {
+  /**
+   * @brief Ventilsteuerungsbefehl (1=Öffnen, 2=Schliessen, 0=Bewegung stoppen).
    */
-enum
-{
-	/* Valve Control */
   REG_HOLDING_VALVE_COMMAND = 0x0000,
+  /**
+   * @brief Sicherheits-Timeout in Sekunden für den Öffnen-Vorgang.
+   */
   REG_HOLDING_MAX_OPENING_TIME_S = 0x0001,
+  /**
+   * @brief Sicherheits-Timeout in Sekunden für den Schliessen-Vorgang.
+   */
   REG_HOLDING_MAX_CLOSING_TIME_S = 0x0002,
-	/* Digital Outputs */
+  /**
+   * @brief Bitmaske zum Lesen und Schreiben der digitalen Ausgänge. Bit 0:
+   * Ausgang 1, Bit 1: Ausgang 2. 1=AN, 0=AUS.
+   */
   REG_HOLDING_DIGITAL_OUTPUTS_STATE = 0x0010,
-	/* System Config */
+  /**
+   * @brief Timeout des Fail-Safe-Watchdogs in Sekunden. 0=Deaktiviert.
+   */
   REG_HOLDING_WATCHDOG_TIMEOUT_S = 0x00F0,
+  /**
+   * @brief Schreiben von 1 startet das Gerät neu.
+   */
   REG_HOLDING_DEVICE_RESET = 0x00F1,
-	/* Firmware Update */
+  /**
+   * @brief Befehl für das Firmware-Update.
+   * 1: Verify Chunk - Slave schreibt den letzten Chunk ins Flash.
+   * 2: Finalize Update - Installation abschliessen und neu starten.
+   */
   REG_HOLDING_FWU_COMMAND = 0x0100,
+  /**
+   * @brief Untere 16 Bit des 32-Bit-Offsets für den nächsten
+   * Firmware-Update-Chunk.
+   */
   REG_HOLDING_FWU_CHUNK_OFFSET_LOW = 0x0101,
+  /**
+   * @brief Obere 16 Bit des 32-Bit-Offsets für den nächsten
+   * Firmware-Update-Chunk.
+   */
   REG_HOLDING_FWU_CHUNK_OFFSET_HIGH = 0x0102,
+  /**
+   * @brief Grösse des nächsten Firmware-Update-Chunks in Bytes (max. 256).
+   */
   REG_HOLDING_FWU_CHUNK_SIZE = 0x0103,
+  /**
+   * @brief Startadresse des 256-Byte-Puffers für Firmware-Update-Daten.
+   */
   REG_HOLDING_FWU_DATA_BUFFER = 0x0180,
 };
 
+/**
+ * @brief Initializes the Modbus server.
+ *
+ * This function sets up the Modbus RTU server interface, loads saved settings
+ * (baudrate, unit ID), and starts listening for requests.
+ *
+ * @return 0 on success, or a negative error code on failure.
+ */
 int modbus_server_init(void);
+
+/**
+ * @brief Reconfigures the Modbus server at runtime.
+ *
+ * Updates the baudrate and unit ID of the server. If the reconfiguration
+ * fails, the settings are saved and will be applied after a device reset.
+ *
+ * @param baudrate The new baudrate to set.
+ * @param unit_id The new Modbus unit ID (slave address).
+ * @return 0 on success, or a negative error code if immediate reconfiguration
+ * fails. Returns 0 even on failure if settings could be saved for the next
+ * boot.
+ */
 int modbus_reconfigure(uint32_t baudrate, uint8_t unit_id);
+
+/**
+ * @brief Gets the current baudrate of the Modbus server.
+ *
+ * @return The current baudrate.
+ */
 uint32_t modbus_get_baudrate(void);
+
+/**
+ * @brief Gets the current unit ID of the Modbus server.
+ *
+ * @return The current unit ID.
+ */
 uint8_t modbus_get_unit_id(void);
 
 #endif  // MODBUS_SERVER_H

software/include/lib/valve.h

@@ -4,33 +4,120 @@
 #include <stdint.h>
 #include <zephyr/drivers/gpio.h>
 
+/**
+ * @file valve.h
+ * @brief API for controlling the motorized valve.
+ *
+ * This library provides functions to initialize, open, close, and stop the
+ * valve. It also allows getting the valve's state and movement status, and
+ * configuring the maximum opening and closing times.
+ */
+
+/**
+ * @brief Defines the GPIO pins used for the valve controller.
+ */
 struct valve_gpios {
-    const struct gpio_dt_spec in0;
-    const struct gpio_dt_spec in1;
-    const struct gpio_dt_spec rst;
-    const struct gpio_dt_spec sen;
-    const struct gpio_dt_spec s0;
-    const struct gpio_dt_spec s1;
+  const struct gpio_dt_spec
+      in0; /**< Control input 0 for the VND7050AJ driver. */
+  const struct gpio_dt_spec
+      in1; /**< Control input 1 for the VND7050AJ driver. */
+  const struct gpio_dt_spec rst; /**< Reset pin for the VND7050AJ driver. */
+  const struct gpio_dt_spec sen; /**< Sense (current measurement) pin. */
+  const struct gpio_dt_spec s0;  /**< S0 select pin. */
+  const struct gpio_dt_spec s1;  /**< S1 select pin. */
 };
 
+/**
+ * @brief Represents the static state of the valve (open or closed).
+ */
 enum valve_state {
-    VALVE_STATE_CLOSED,
-    VALVE_STATE_OPEN,
+  VALVE_STATE_CLOSED, /**< The valve is fully closed. */
+  VALVE_STATE_OPEN,   /**< The valve is fully open. */
 };
-enum valve_movement { VALVE_MOVEMENT_IDLE, VALVE_MOVEMENT_OPENING, VALVE_MOVEMENT_CLOSING, VALVE_MOVEMENT_ERROR };
 
+/**
+ * @brief Represents the dynamic movement status of the valve.
+ */
+enum valve_movement {
+  VALVE_MOVEMENT_IDLE,    /**< The valve is not moving. */
+  VALVE_MOVEMENT_OPENING, /**< The valve is currently opening. */
+  VALVE_MOVEMENT_CLOSING, /**< The valve is currently closing. */
+  VALVE_MOVEMENT_ERROR    /**< An error occurred during movement. */
+};
+
+/**
+ * @brief Initializes the valve control system.
+ *
+ * Configures the GPIOs and loads saved settings for timeouts.
+ */
 void valve_init(void);
+
+/**
+ * @brief Starts opening the valve.
+ *
+ * The valve will open for the configured maximum opening time.
+ */
 void valve_open(void);
+
+/**
+ * @brief Starts closing the valve.
+ *
+ * The valve will close for the configured maximum closing time.
+ */
 void valve_close(void);
+
+/**
+ * @brief Stops any ongoing valve movement immediately.
+ */
 void valve_stop(void);
 
+/**
+ * @brief Gets the current static state of the valve.
+ *
+ * @return The current valve state (VALVE_STATE_CLOSED or VALVE_STATE_OPEN).
+ */
 enum valve_state valve_get_state(void);
+
+/**
+ * @brief Gets the current movement status of the valve.
+ *
+ * @return The current movement status.
+ */
 enum valve_movement valve_get_movement(void);
+
+/**
+ * @brief Gets the motor current.
+ *
+ * @return The motor current in milliamps (currently simulated).
+ */
 uint16_t valve_get_motor_current(void);
 
+/**
+ * @brief Sets the maximum time for the valve to open.
+ *
+ * @param seconds The timeout in seconds.
+ */
 void valve_set_max_open_time(uint16_t seconds);
+
+/**
+ * @brief Sets the maximum time for the valve to close.
+ *
+ * @param seconds The timeout in seconds.
+ */
 void valve_set_max_close_time(uint16_t seconds);
+
+/**
+ * @brief Gets the configured maximum opening time.
+ *
+ * @return The timeout in seconds.
+ */
 uint16_t valve_get_max_open_time(void);
+
+/**
+ * @brief Gets the configured maximum closing time.
+ *
+ * @return The timeout in seconds.
+ */
 uint16_t valve_get_max_close_time(void);
 
 #endif  // VALVE_H

software/lib/CMakeLists.txt

@@ -1,3 +1,4 @@
+add_subdirectory_ifdef(CONFIG_ADC_SENSOR adc_sensor)
 add_subdirectory_ifdef(CONFIG_LIB_FWU fwu)
 add_subdirectory_ifdef(CONFIG_LIB_MODBUS_SERVER modbus_server)
 add_subdirectory_ifdef(CONFIG_LIB_VALVE valve)

software/lib/Kconfig

@@ -1,5 +1,6 @@
 menu "Irrigation system software libraries"
 
+rsource "adc_sensor/Kconfig"
 rsource "fwu/Kconfig"
 rsource "modbus_server/Kconfig"
 rsource "valve/Kconfig"

software/lib/adc_sensor/CMakeLists.txt

@@ -0,0 +1 @@
+zephyr_library_sources(adc_sensor.c)

software/lib/adc_sensor/Kconfig

@@ -0,0 +1,16 @@
+config ADC_SENSOR
+	bool "ADC sensor library"
+	default y
+	help
+	  Enable ADC sensor library for voltage and current measurements.
+
+if ADC_SENSOR
+
+config ADC_SENSOR_SIMULATED
+	bool "Use simulated ADC readings"
+	default n
+	help
+	  Use simulated values instead of real ADC readings.
+	  Voltage: 12000mV, Current: 45mA
+
+endif # ADC_SENSOR

software/lib/adc_sensor/adc_sensor.c

@@ -0,0 +1,347 @@
+/**
+ * @file adc_sensor.c
+ * @brief Implementation of the ADC sensor library.
+ *
+ * This file contains the implementation for initializing and reading from ADC
+ * sensors. It currently provides simulated values for voltage and current, with
+ * placeholders for real hardware ADC implementation including GPIO control.
+ */
+
+#include <lib/adc_sensor.h>
+#include <zephyr/devicetree.h>
+#include <zephyr/drivers/adc.h>
+#include <zephyr/drivers/gpio.h>
+#include <zephyr/kernel.h>
+#include <zephyr/logging/log.h>
+
+LOG_MODULE_REGISTER(adc_sensor, LOG_LEVEL_INF);
+
+// Simulated values
+#define SIMULATED_VOLTAGE_MV 12000
+#define SIMULATED_CURRENT_MA 45
+
+// Devicetree node checks
+#define VOLTAGE_SENSOR_NODE DT_NODELABEL(supply_voltage)
+#define CURRENT_SENSOR_NODE DT_NODELABEL(motor_current)
+
+#ifndef CONFIG_ADC_SENSOR_SIMULATED
+// ADC device reference
+#if DT_NODE_EXISTS(VOLTAGE_SENSOR_NODE)
+#define ADC_NODE DT_PHANDLE(VOLTAGE_SENSOR_NODE, io_channels)
+#define ADC_CHANNEL DT_PHA(VOLTAGE_SENSOR_NODE, io_channels, input)
+#define ADC_RESOLUTION 12
+#define ADC_REFERENCE_MV DT_PROP(VOLTAGE_SENSOR_NODE, reference_mv)
+#define VOLTAGE_DIVIDER_RATIO \
+  DT_PROP(VOLTAGE_SENSOR_NODE, voltage_divider_ratio)
+
+static const struct device *adc_dev;
+static struct adc_channel_cfg adc_channel_cfg = {
+    .gain = ADC_GAIN_1,
+    .reference = ADC_REF_INTERNAL,
+    .acquisition_time = ADC_ACQ_TIME_DEFAULT,
+    .channel_id = ADC_CHANNEL,
+    .differential = 0};
+
+static struct adc_sequence adc_sequence = {
+    .channels = BIT(ADC_CHANNEL),
+    .buffer_size = sizeof(uint16_t),
+    .resolution = ADC_RESOLUTION,
+};
+
+static uint16_t adc_buffer;
+#endif
+#endif
+
+static bool initialized = false;
+
+#ifndef CONFIG_ADC_SENSOR_SIMULATED
+// GPIO specs for voltage sensor (if devicetree nodes exist)
+#if DT_NODE_EXISTS(VOLTAGE_SENSOR_NODE)
+static const struct gpio_dt_spec voltage_sen_gpio =
+    GPIO_DT_SPEC_GET(VOLTAGE_SENSOR_NODE, sen_gpios);
+static const struct gpio_dt_spec voltage_s0_gpio =
+    GPIO_DT_SPEC_GET(VOLTAGE_SENSOR_NODE, s0_gpios);
+static const struct gpio_dt_spec voltage_s1_gpio =
+    GPIO_DT_SPEC_GET(VOLTAGE_SENSOR_NODE, s1_gpios);
+#endif
+
+// GPIO specs for current sensor (if devicetree nodes exist)
+#if DT_NODE_EXISTS(CURRENT_SENSOR_NODE)
+static const struct gpio_dt_spec current_sen_gpio =
+    GPIO_DT_SPEC_GET(CURRENT_SENSOR_NODE, sen_gpios);
+static const struct gpio_dt_spec current_s0_gpio =
+    GPIO_DT_SPEC_GET(CURRENT_SENSOR_NODE, s0_gpios);
+static const struct gpio_dt_spec current_s1_gpio =
+    GPIO_DT_SPEC_GET(CURRENT_SENSOR_NODE, s1_gpios);
+#endif
+
+/**
+ * @brief Configure GPIO pins for ADC sensor control
+ */
+static int configure_sensor_gpios(void) {
+  int ret = 0;
+
+#if DT_NODE_EXISTS(VOLTAGE_SENSOR_NODE)
+  // Configure voltage sensor GPIOs
+  if (gpio_is_ready_dt(&voltage_sen_gpio)) {
+    ret = gpio_pin_configure_dt(&voltage_sen_gpio, GPIO_OUTPUT_INACTIVE);
+    if (ret < 0) {
+      LOG_ERR("Failed to configure voltage sen GPIO: %d", ret);
+      return ret;
+    }
+  }
+
+  if (gpio_is_ready_dt(&voltage_s0_gpio)) {
+    ret = gpio_pin_configure_dt(&voltage_s0_gpio, GPIO_OUTPUT_INACTIVE);
+    if (ret < 0) {
+      LOG_ERR("Failed to configure voltage s0 GPIO: %d", ret);
+      return ret;
+    }
+  }
+
+  if (gpio_is_ready_dt(&voltage_s1_gpio)) {
+    ret = gpio_pin_configure_dt(&voltage_s1_gpio, GPIO_OUTPUT_INACTIVE);
+    if (ret < 0) {
+      LOG_ERR("Failed to configure voltage s1 GPIO: %d", ret);
+      return ret;
+    }
+  }
+#endif
+
+#if DT_NODE_EXISTS(CURRENT_SENSOR_NODE)
+  // Configure current sensor GPIOs
+  if (gpio_is_ready_dt(&current_sen_gpio)) {
+    ret = gpio_pin_configure_dt(&current_sen_gpio, GPIO_OUTPUT_INACTIVE);
+    if (ret < 0) {
+      LOG_ERR("Failed to configure current sen GPIO: %d", ret);
+      return ret;
+    }
+  }
+
+  if (gpio_is_ready_dt(&current_s0_gpio)) {
+    ret = gpio_pin_configure_dt(&current_s0_gpio, GPIO_OUTPUT_INACTIVE);
+    if (ret < 0) {
+      LOG_ERR("Failed to configure current s0 GPIO: %d", ret);
+      return ret;
+    }
+  }
+
+  if (gpio_is_ready_dt(&current_s1_gpio)) {
+    ret = gpio_pin_configure_dt(&current_s1_gpio, GPIO_OUTPUT_INACTIVE);
+    if (ret < 0) {
+      LOG_ERR("Failed to configure current s1 GPIO: %d", ret);
+      return ret;
+    }
+  }
+#endif
+
+  return 0;
+}
+
+/**
+ * @brief Set GPIO pins for voltage measurement
+ * @param s0_state State for S0 pin (multiplexer bit 0)
+ * @param s1_state State for S1 pin (multiplexer bit 1)
+ */
+static int set_voltage_sensor_gpios(bool enable, bool s0_state, bool s1_state) {
+#if DT_NODE_EXISTS(VOLTAGE_SENSOR_NODE)
+  if (gpio_is_ready_dt(&voltage_sen_gpio)) {
+    gpio_pin_set_dt(&voltage_sen_gpio, enable ? 1 : 0);
+  }
+  if (gpio_is_ready_dt(&voltage_s0_gpio)) {
+    gpio_pin_set_dt(&voltage_s0_gpio, s0_state ? 1 : 0);
+  }
+  if (gpio_is_ready_dt(&voltage_s1_gpio)) {
+    gpio_pin_set_dt(&voltage_s1_gpio, s1_state ? 1 : 0);
+  }
+
+  // Delay for GPIO settling (from devicetree or default)
+#if DT_NODE_HAS_PROP(VOLTAGE_SENSOR_NODE, measurement_delay_ms)
+  k_msleep(DT_PROP(VOLTAGE_SENSOR_NODE, measurement_delay_ms));
+#else
+  k_msleep(5);  // Default 5ms delay
+#endif
+#endif
+  return 0;
+}
+
+/**
+ * @brief Set GPIO pins for current measurement
+ * @param s0_state State for S0 pin (multiplexer bit 0)
+ * @param s1_state State for S1 pin (multiplexer bit 1)
+ */
+static int set_current_sensor_gpios(bool enable, bool s0_state, bool s1_state) {
+#if DT_NODE_EXISTS(CURRENT_SENSOR_NODE)
+  if (gpio_is_ready_dt(&current_sen_gpio)) {
+    gpio_pin_set_dt(&current_sen_gpio, enable ? 1 : 0);
+  }
+  if (gpio_is_ready_dt(&current_s0_gpio)) {
+    gpio_pin_set_dt(&current_s0_gpio, s0_state ? 1 : 0);
+  }
+  if (gpio_is_ready_dt(&current_s1_gpio)) {
+    gpio_pin_set_dt(&current_s1_gpio, s1_state ? 1 : 0);
+  }
+
+  // Delay for GPIO settling (from devicetree or default)
+#if DT_NODE_HAS_PROP(CURRENT_SENSOR_NODE, measurement_delay_ms)
+  k_msleep(DT_PROP(CURRENT_SENSOR_NODE, measurement_delay_ms));
+#else
+  k_msleep(10);  // Default 10ms delay
+#endif
+#endif
+  return 0;
+}
+#endif /* !CONFIG_ADC_SENSOR_SIMULATED */
+
+#ifndef CONFIG_ADC_SENSOR_SIMULATED
+/**
+ * @brief Read ADC value and convert to millivolts
+ * @return ADC reading in millivolts, or 0 on error
+ */
+static uint16_t read_adc_voltage_mv(void) {
+#if DT_NODE_EXISTS(VOLTAGE_SENSOR_NODE)
+  int ret = adc_read(adc_dev, &adc_sequence);
+  if (ret < 0) {
+    LOG_ERR("ADC read failed: %d", ret);
+    return 0;
+  }
+
+  // Convert ADC reading to millivolts
+  // ADC reading is 12-bit (0-4095) representing 0 to ADC_REFERENCE_MV
+  uint32_t adc_value = adc_buffer;
+  uint32_t voltage_mv = (adc_value * ADC_REFERENCE_MV) / 4095;
+
+  // Apply voltage divider scaling
+  voltage_mv *= VOLTAGE_DIVIDER_RATIO;
+
+  LOG_DBG("ADC raw: %u, voltage: %u mV", adc_value, (uint16_t)voltage_mv);
+
+  return (uint16_t)voltage_mv;
+#else
+  return 0;
+#endif
+}
+
+/**
+ * @brief Read ADC value and convert to milliamps (for current sensor)
+ * @return ADC reading in milliamps, or 0 on error
+ */
+static uint16_t read_adc_current_ma(void) {
+#if DT_NODE_EXISTS(CURRENT_SENSOR_NODE)
+  int ret = adc_read(adc_dev, &adc_sequence);
+  if (ret < 0) {
+    LOG_ERR("ADC read failed: %d", ret);
+    return 0;
+  }
+
+  // Convert ADC reading to millivolts first
+  uint32_t adc_value = adc_buffer;
+  uint32_t voltage_mv = (adc_value * ADC_REFERENCE_MV) / 4095;
+
+  // Convert voltage to current based on current sensor characteristics
+  // Assuming a linear current sensor with specific mV/mA ratio
+  // This will need to be calibrated for your specific current sensor
+  uint32_t current_ma = voltage_mv / 10;  // Example: 10mV per mA
+
+  LOG_DBG("ADC raw: %u, current: %u mA", adc_value, (uint16_t)current_ma);
+
+  return (uint16_t)current_ma;
+#else
+  return 0;
+#endif
+}
+#endif
+
+int adc_sensor_init(void) {
+  if (initialized) {
+    return 0;
+  }
+
+#ifdef CONFIG_ADC_SENSOR_SIMULATED
+  LOG_INF("ADC sensor initialized (simulated mode)");
+  LOG_INF("Simulated values: %dmV, %dmA", SIMULATED_VOLTAGE_MV,
+          SIMULATED_CURRENT_MA);
+#else
+  // Initialize GPIO pins for sensor control
+  int ret = configure_sensor_gpios();
+  if (ret < 0) {
+    LOG_ERR("Failed to configure sensor GPIOs: %d", ret);
+    return ret;
+  }
+
+  // Initialize ADC hardware
+#if DT_NODE_EXISTS(VOLTAGE_SENSOR_NODE)
+  adc_dev = DEVICE_DT_GET(ADC_NODE);
+  if (!device_is_ready(adc_dev)) {
+    LOG_ERR("ADC device not ready");
+    return -ENODEV;
+  }
+
+  adc_sequence.buffer = &adc_buffer;
+
+  ret = adc_channel_setup(adc_dev, &adc_channel_cfg);
+  if (ret < 0) {
+    LOG_ERR("Failed to setup ADC channel: %d", ret);
+    return ret;
+  }
+
+  LOG_INF("ADC device ready: %s", adc_dev->name);
+#endif
+
+  LOG_INF("ADC sensor initialized (real ADC mode with GPIO control)");
+
+#if DT_NODE_EXISTS(VOLTAGE_SENSOR_NODE)
+  LOG_INF("Voltage sensor found in devicetree");
+#endif
+#if DT_NODE_EXISTS(CURRENT_SENSOR_NODE)
+  LOG_INF("Current sensor found in devicetree");
+#endif
+#endif
+
+  initialized = true;
+  return 0;
+}
+
+uint16_t adc_sensor_get_voltage_mv(void) {
+  if (!initialized) {
+    LOG_WRN("ADC sensor not initialized, calling adc_sensor_init()");
+    adc_sensor_init();
+  }
+
+#ifdef CONFIG_ADC_SENSOR_SIMULATED
+  return SIMULATED_VOLTAGE_MV;
+#else
+  // Set GPIOs for voltage measurement (example: s0=0, s1=0 for channel 0)
+  set_voltage_sensor_gpios(true, false, false);
+
+  // Read real ADC value for voltage
+  uint16_t voltage = read_adc_voltage_mv();
+
+  // Disable sensor after measurement to save power
+  set_voltage_sensor_gpios(false, false, false);
+
+  return voltage;
+#endif
+}
+
+uint16_t adc_sensor_get_current_ma(void) {
+  if (!initialized) {
+    LOG_WRN("ADC sensor not initialized, calling adc_sensor_init()");
+    adc_sensor_init();
+  }
+
+#ifdef CONFIG_ADC_SENSOR_SIMULATED
+  return SIMULATED_CURRENT_MA;
+#else
+  // Set GPIOs for current measurement (example: s0=1, s1=0 for channel 1)
+  set_current_sensor_gpios(true, true, false);
+
+  // Read real ADC value for current
+  uint16_t current = read_adc_current_ma();
+
+  // Disable sensor after measurement to save power
+  set_current_sensor_gpios(false, false, false);
+
+  return current;
+#endif
+}

software/lib/fwu/fwu.c

@@ -1,26 +1,42 @@
-#include <zephyr/kernel.h>
-#include <zephyr/sys/crc.h>
-#include <zephyr/sys/byteorder.h>
-#include <zephyr/logging/log.h>
+/**
+ * @file fwu.c
+ * @brief Implementation of the Firmware Update (FWU) library.
+ *
+ * This file implements the logic for receiving a new firmware image in chunks
+ * over Modbus. It maintains a buffer for the incoming data, calculates the CRC
+ * of the received chunk, and handles commands to verify the chunk and finalize
+ * the update process. The actual writing to flash is simulated.
+ */
+
 #include <lib/fwu.h>
+#include <zephyr/kernel.h>
+#include <zephyr/logging/log.h>
+#include <zephyr/sys/byteorder.h>
+#include <zephyr/sys/crc.h>
 
 LOG_MODULE_REGISTER(fwu, LOG_LEVEL_INF);
 
 #define FWU_BUFFER_SIZE 256
-static uint8_t fwu_buffer[FWU_BUFFER_SIZE];
-static uint32_t fwu_chunk_offset = 0;
-static uint16_t fwu_chunk_size = 0;
-static uint16_t fwu_last_chunk_crc = 0;
+static uint8_t fwu_buffer[FWU_BUFFER_SIZE];  // Buffer to store incoming
+                                             // firmware data chunks
+static uint32_t fwu_chunk_offset =
+    0;  // Offset for the current firmware chunk in the overall image
+static uint16_t fwu_chunk_size = 0;  // Size of the current firmware chunk
+static uint16_t fwu_last_chunk_crc =
+    0;  // CRC16 of the last received firmware chunk
 
 void fwu_init(void) {}
 
-void fwu_handler(uint16_t addr, uint16_t reg)
-{
-    // This is a simplified handler. In a real scenario, you would have a proper mapping
-    // between register addresses and actions.
+void fwu_handler(uint16_t addr, uint16_t reg) {
+  // This is a simplified handler. In a real scenario, you would have a proper
+  // mapping between register addresses and actions.
   if (addr == 0x0100) {  // FWU_COMMAND
-        if (reg == 1) { LOG_INF("FWU: Chunk at offset %u (size %u) verified.", fwu_chunk_offset, fwu_chunk_size); }
-        else if (reg == 2) { LOG_INF("FWU: Finalize command received. Rebooting (simulated)."); }
+    if (reg == 1) {
+      LOG_INF("FWU: Chunk at offset %u (size %u) verified.", fwu_chunk_offset,
+              fwu_chunk_size);
+    } else if (reg == 2) {
+      LOG_INF("FWU: Finalize command received. Rebooting (simulated).");
+    }
   } else if (addr == 0x0101) {  // FWU_CHUNK_OFFSET_LOW
     fwu_chunk_offset = (fwu_chunk_offset & 0xFFFF0000) | reg;
   } else if (addr == 0x0102) {  // FWU_CHUNK_OFFSET_HIGH
@@ -39,7 +55,4 @@ void fwu_handler(uint16_t addr, uint16_t reg)
   }
 }
 
-uint16_t fwu_get_last_chunk_crc(void)
-{
-    return fwu_last_chunk_crc;
-}
+uint16_t fwu_get_last_chunk_crc(void) { return fwu_last_chunk_crc; }

software/lib/modbus_server/modbus_server.c

@@ -1,14 +1,24 @@
-#include <zephyr/kernel.h>
-#include <zephyr/drivers/uart.h>
-#include <zephyr/device.h>
-#include <zephyr/modbus/modbus.h>
-#include <zephyr/logging/log.h>
-#include <zephyr/settings/settings.h>
-#include <zephyr/sys/reboot.h>
+/**
+ * @file modbus_server.c
+ * @brief Modbus RTU server implementation for the irrigation system slave node.
+ *
+ * This file implements the Modbus server logic, including register callbacks,
+ * watchdog handling, and dynamic reconfiguration. It interfaces with other
+ * libraries like valve control, ADC sensors, and firmware updates.
+ */
+
+#include <app_version.h>
+#include <lib/adc_sensor.h>
+#include <lib/fwu.h>
 #include <lib/modbus_server.h>
 #include <lib/valve.h>
-#include <lib/fwu.h>
-
+#include <zephyr/device.h>
+#include <zephyr/drivers/uart.h>
+#include <zephyr/kernel.h>
+#include <zephyr/logging/log.h>
+#include <zephyr/modbus/modbus.h>
+#include <zephyr/settings/settings.h>
+#include <zephyr/sys/reboot.h>
 #include <zephyr/usb/usb_device.h>
 
 LOG_MODULE_REGISTER(modbus_server, LOG_LEVEL_INF);
@@ -23,25 +33,42 @@ static struct modbus_iface_param server_param = {
 static uint16_t watchdog_timeout_s = 0;
 static struct k_timer watchdog_timer;
 
-static void watchdog_timer_handler(struct k_timer *timer_id)
-{
+/**
+ * @brief Timer handler for the Modbus watchdog.
+ *
+ * This function is called when the watchdog timer expires, indicating a loss
+ * of communication with the Modbus master. It triggers a fail-safe action,
+ * which is to close the valve.
+ *
+ * @param timer_id Pointer to the timer instance.
+ */
+static void watchdog_timer_handler(struct k_timer *timer_id) {
   LOG_WRN("Modbus watchdog expired! Closing valve as a fail-safe.");
   valve_close();
 }
 
-static inline void reset_watchdog(void)
-{
-	if (watchdog_timeout_s > 0)
-	{
+/**
+ * @brief Resets the Modbus watchdog timer.
+ *
+ * This function should be called upon receiving any valid Modbus request
+ * to prevent the watchdog from expiring.
+ */
+static inline void reset_watchdog(void) {
+  if (watchdog_timeout_s > 0) {
     k_timer_start(&watchdog_timer, K_SECONDS(watchdog_timeout_s), K_NO_WAIT);
   }
 }
 
-static int holding_reg_rd(uint16_t addr, uint16_t *reg)
-{
+/**
+ * @brief Callback for reading Modbus holding registers.
+ *
+ * @param addr Register address.
+ * @param reg Pointer to store the read value.
+ * @return 0 on success.
+ */
+static int holding_reg_rd(uint16_t addr, uint16_t *reg) {
   reset_watchdog();
-	switch (addr)
-	{
+  switch (addr) {
     case REG_HOLDING_MAX_OPENING_TIME_S:
       *reg = valve_get_max_open_time();
       break;
@@ -58,22 +85,22 @@ static int holding_reg_rd(uint16_t addr, uint16_t *reg)
   return 0;
 }
 
-static int holding_reg_wr(uint16_t addr, uint16_t reg)
-{
+/**
+ * @brief Callback for writing Modbus holding registers.
+ *
+ * @param addr Register address.
+ * @param reg Value to write.
+ * @return 0 on success.
+ */
+static int holding_reg_wr(uint16_t addr, uint16_t reg) {
   reset_watchdog();
-	switch (addr)
-	{
+  switch (addr) {
     case REG_HOLDING_VALVE_COMMAND:
-		if (reg == 1)
-		{
+      if (reg == 1) {
         valve_open();
-		}
-		else if (reg == 2)
-		{
+      } else if (reg == 2) {
         valve_close();
-		}
-		else if (reg == 0)
-		{
+      } else if (reg == 0) {
         valve_stop();
       }
       break;
@@ -85,20 +112,16 @@ static int holding_reg_wr(uint16_t addr, uint16_t reg)
       break;
     case REG_HOLDING_WATCHDOG_TIMEOUT_S:
       watchdog_timeout_s = reg;
-		if (watchdog_timeout_s > 0)
-		{
+      if (watchdog_timeout_s > 0) {
         LOG_INF("Watchdog enabled with %u s timeout.", watchdog_timeout_s);
         reset_watchdog();
-		}
-		else
-		{
+      } else {
         LOG_INF("Watchdog disabled.");
         k_timer_stop(&watchdog_timer);
       }
       break;
     case REG_HOLDING_DEVICE_RESET:
-		if (reg == 1)
-		{
+      if (reg == 1) {
         LOG_WRN("Modbus reset command received. Rebooting...");
         sys_reboot(SYS_REBOOT_WARM);
       }
@@ -110,17 +133,22 @@ static int holding_reg_wr(uint16_t addr, uint16_t reg)
   return 0;
 }
 
-static int input_reg_rd(uint16_t addr, uint16_t *reg)
-{
+/**
+ * @brief Callback for reading Modbus input registers.
+ *
+ * @param addr Register address.
+ * @param reg Pointer to store the read value.
+ * @return 0 on success.
+ */
+static int input_reg_rd(uint16_t addr, uint16_t *reg) {
   reset_watchdog();
   uint32_t uptime_s = k_uptime_get_32() / 1000;
-	switch (addr)
-	{
+  switch (addr) {
     case REG_INPUT_VALVE_STATE_MOVEMENT:
       *reg = (valve_get_movement() << 8) | (valve_get_state() & 0xFF);
       break;
     case REG_INPUT_MOTOR_CURRENT_MA:
-		*reg = valve_get_motor_current();
+      *reg = adc_sensor_get_current_ma();
       break;
     case REG_INPUT_UPTIME_SECONDS_LOW:
       *reg = (uint16_t)(uptime_s & 0xFFFF);
@@ -129,16 +157,16 @@ static int input_reg_rd(uint16_t addr, uint16_t *reg)
       *reg = (uint16_t)(uptime_s >> 16);
       break;
     case REG_INPUT_SUPPLY_VOLTAGE_MV:
-		*reg = 12300;
+      *reg = adc_sensor_get_voltage_mv();
       break;
     case REG_INPUT_FWU_LAST_CHUNK_CRC:
       *reg = fwu_get_last_chunk_crc();
       break;
     case REG_INPUT_FIRMWARE_VERSION_MAJOR_MINOR:
-		*reg = (0 << 8) | 0;
+      *reg = (APP_VERSION_MAJOR << 8) | APP_VERSION_MINOR;
       break;
     case REG_INPUT_FIRMWARE_VERSION_PATCH:
-		*reg = 2;
+      *reg = APP_PATCHLEVEL;
       break;
     default:
       *reg = 0;
@@ -148,6 +176,7 @@ static int input_reg_rd(uint16_t addr, uint16_t *reg)
 }
 
 static struct modbus_user_callbacks mbs_cbs = {
+    // Modbus server callback functions
     .holding_reg_rd = holding_reg_rd,
     .holding_reg_wr = holding_reg_wr,
     .input_reg_rd = input_reg_rd,
@@ -155,10 +184,16 @@ static struct modbus_user_callbacks mbs_cbs = {
 
 #define MODBUS_NODE DT_COMPAT_GET_ANY_STATUS_OKAY(zephyr_modbus_serial)
 
-int modbus_server_init(void)
-{
+int modbus_server_init(void) {
   k_timer_init(&watchdog_timer, watchdog_timer_handler, NULL);
 
+  // Initialize ADC sensor
+  int ret = adc_sensor_init();
+  if (ret < 0) {
+    LOG_ERR("Failed to initialize ADC sensor: %d", ret);
+    return ret;
+  }
+
   // Load saved settings
   uint32_t saved_baudrate = 19200;
   uint8_t saved_unit_id = 1;
@@ -174,13 +209,11 @@ int modbus_server_init(void)
   const struct device *const dev = DEVICE_DT_GET(DT_PARENT(MODBUS_NODE));
   uint32_t dtr = 0;
 
-	if (!device_is_ready(dev) || usb_enable(NULL))
-	{
+  if (!device_is_ready(dev) || usb_enable(NULL)) {
     return 0;
   }
 
-	while (!dtr)
-	{
+  while (!dtr) {
     uart_line_ctrl_get(dev, UART_LINE_CTRL_DTR, &dtr);
     k_sleep(K_MSEC(100));
   }
@@ -188,18 +221,17 @@ int modbus_server_init(void)
   LOG_INF("Client connected to server on %s", dev->name);
 #endif
   modbus_iface = modbus_iface_get_by_name(iface_name);
-	if (modbus_iface < 0)
-	{
+  if (modbus_iface < 0) {
     return modbus_iface;
   }
   server_param.server.user_cb = &mbs_cbs;
 
-	LOG_INF("Starting Modbus server: baudrate=%u, unit_id=%u", saved_baudrate, saved_unit_id);
+  LOG_INF("Starting Modbus server: baudrate=%u, unit_id=%u", saved_baudrate,
+          saved_unit_id);
   return modbus_init_server(modbus_iface, server_param);
 }
 
-int modbus_reconfigure(uint32_t baudrate, uint8_t unit_id)
-{
+int modbus_reconfigure(uint32_t baudrate, uint8_t unit_id) {
   // Update parameters
   server_param.serial.baud = baudrate;
   server_param.server.unit_id = unit_id;
@@ -207,14 +239,11 @@ int modbus_reconfigure(uint32_t baudrate, uint8_t unit_id)
   // Try to reinitialize - this should work for most cases
   int ret = modbus_init_server(modbus_iface, server_param);
 
-	if (ret == 0)
-	{
+  if (ret == 0) {
     settings_save_one("modbus/baudrate", &baudrate, sizeof(baudrate));
     settings_save_one("modbus/unit_id", &unit_id, sizeof(unit_id));
     LOG_INF("Modbus reconfigured: baudrate=%u, unit_id=%u", baudrate, unit_id);
-	}
-	else
-	{
+  } else {
     LOG_ERR("Failed to reconfigure Modbus: %d", ret);
     LOG_INF("Modbus reconfiguration requires restart to take effect");
 
@@ -222,7 +251,9 @@ int modbus_reconfigure(uint32_t baudrate, uint8_t unit_id)
     settings_save_one("modbus/baudrate", &baudrate, sizeof(baudrate));
     settings_save_one("modbus/unit_id", &unit_id, sizeof(unit_id));
 
-		LOG_INF("Settings saved. Type 'reset' to restart the device and apply the change.");
+    LOG_INF(
+        "Settings saved. Type 'reset' to restart the device and apply the "
+        "change.");
     return 0;  // Return success since settings are saved
   }
 

software/lib/shell_modbus/shell_modbus.c

@@ -1,17 +1,36 @@
-#include <zephyr/shell/shell.h>
-#include <stdlib.h>
+/**
+ * @file shell_modbus.c
+ * @brief Provides shell commands for Modbus and valve configuration.
+ *
+ * This file implements a set of commands for the Zephyr shell to allow
+ * runtime configuration of the Modbus server (baudrate, slave ID) and the
+ * valve (max opening/closing times). The settings are persisted to non-volatile
+ * storage.
+ */
+
 #include <lib/modbus_server.h>
 #include <lib/valve.h>
+#include <stdlib.h>
+#include <zephyr/shell/shell.h>
 
-static int cmd_modbus_set_baud(const struct shell *sh, size_t argc, char **argv)
-{
+/**
+ * @brief Shell command to set the Modbus baudrate.
+ *
+ * @param sh The shell instance.
+ * @param argc Argument count.
+ * @param argv Argument values.
+ * @return 0 on success, -EINVAL on error.
+ */
+static int cmd_modbus_set_baud(const struct shell *sh, size_t argc,
+                               char **argv) {
   if (argc != 2) {
     shell_error(sh, "Usage: set_baud <baudrate>");
     return -EINVAL;
   }
 
   uint32_t new_baud = (uint32_t)strtoul(argv[1], NULL, 10);
-	const uint32_t valid_baud_rates[] = {1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200};
+  const uint32_t valid_baud_rates[] = {1200,  2400,  4800,  9600,
+                                       19200, 38400, 57600, 115200};
   bool is_valid = false;
 
   for (int i = 0; i < ARRAY_SIZE(valid_baud_rates); i++) {
@@ -23,9 +42,11 @@ static int cmd_modbus_set_baud(const struct shell *sh, size_t argc, char **argv)
 
   if (!is_valid) {
     char error_msg[128];
-		int offset = snprintf(error_msg, sizeof(error_msg), "Invalid baudrate. Valid rates are: ");
+    int offset = snprintf(error_msg, sizeof(error_msg),
+                          "Invalid baudrate. Valid rates are: ");
     for (int i = 0; i < ARRAY_SIZE(valid_baud_rates); i++) {
-			offset += snprintf(error_msg + offset, sizeof(error_msg) - offset, "%u ", valid_baud_rates[i]);
+      offset += snprintf(error_msg + offset, sizeof(error_msg) - offset, "%u ",
+                         valid_baud_rates[i]);
     }
     shell_error(sh, "%s", error_msg);
     return -EINVAL;
@@ -40,8 +61,15 @@ static int cmd_modbus_set_baud(const struct shell *sh, size_t argc, char **argv)
   return 0;
 }
 
-static int cmd_modbus_set_id(const struct shell *sh, size_t argc, char **argv)
-{
+/**
+ * @brief Shell command to set the Modbus slave ID.
+ *
+ * @param sh The shell instance.
+ * @param argc Argument count.
+ * @param argv Argument values.
+ * @return 0 on success, -EINVAL on error.
+ */
+static int cmd_modbus_set_id(const struct shell *sh, size_t argc, char **argv) {
   if (argc != 2) {
     shell_error(sh, "Usage: set_id <slave_id>");
     return -EINVAL;
@@ -49,7 +77,8 @@ static int cmd_modbus_set_id(const struct shell *sh, size_t argc, char **argv)
 
   uint32_t new_id_u32 = (uint32_t)strtoul(argv[1], NULL, 10);
   if (new_id_u32 == 0 || new_id_u32 > 247) {
-		shell_error(sh, "Invalid slave ID: %s. Must be between 1 and 247.", argv[1]);
+    shell_error(sh, "Invalid slave ID: %s. Must be between 1 and 247.",
+                argv[1]);
     return -EINVAL;
   }
   uint8_t new_id = (uint8_t)new_id_u32;
@@ -63,8 +92,16 @@ static int cmd_modbus_set_id(const struct shell *sh, size_t argc, char **argv)
   return 0;
 }
 
-static int cmd_valve_set_open_time(const struct shell *sh, size_t argc, char **argv)
-{
+/**
+ * @brief Shell command to set the valve's maximum opening time.
+ *
+ * @param sh The shell instance.
+ * @param argc Argument count.
+ * @param argv Argument values.
+ * @return 0 on success, -EINVAL on error.
+ */
+static int cmd_valve_set_open_time(const struct shell *sh, size_t argc,
+                                   char **argv) {
   if (argc != 2) {
     shell_error(sh, "Usage: set_open_time <seconds>");
     return -EINVAL;
@@ -77,8 +114,16 @@ static int cmd_valve_set_open_time(const struct shell *sh, size_t argc, char **a
   return 0;
 }
 
-static int cmd_valve_set_close_time(const struct shell *sh, size_t argc, char **argv)
-{
+/**
+ * @brief Shell command to set the valve's maximum closing time.
+ *
+ * @param sh The shell instance.
+ * @param argc Argument count.
+ * @param argv Argument values.
+ * @return 0 on success, -EINVAL on error.
+ */
+static int cmd_valve_set_close_time(const struct shell *sh, size_t argc,
+                                    char **argv) {
   if (argc != 2) {
     shell_error(sh, "Usage: set_close_time <seconds>");
     return -EINVAL;
@@ -91,8 +136,15 @@ static int cmd_valve_set_close_time(const struct shell *sh, size_t argc, char **
   return 0;
 }
 
-static int cmd_config_show(const struct shell *sh, size_t argc, char **argv)
-{
+/**
+ * @brief Shell command to show the current configuration.
+ *
+ * @param sh The shell instance.
+ * @param argc Argument count.
+ * @param argv Argument values.
+ * @return 0 on success.
+ */
+static int cmd_config_show(const struct shell *sh, size_t argc, char **argv) {
   shell_print(sh, "Current Modbus Configuration:");
   shell_print(sh, "  Baudrate: %u", modbus_get_baudrate());
   shell_print(sh, "  Slave ID: %u", modbus_get_unit_id());
@@ -103,17 +155,22 @@ static int cmd_config_show(const struct shell *sh, size_t argc, char **argv)
 }
 
 SHELL_STATIC_SUBCMD_SET_CREATE(sub_modbus_cmds,
-	SHELL_CMD(set_baud, NULL, "Set Modbus baudrate", cmd_modbus_set_baud),
-	SHELL_CMD(set_id,   NULL, "Set Modbus slave ID", cmd_modbus_set_id),
-	SHELL_SUBCMD_SET_END
-);
+                               SHELL_CMD(set_baud, NULL, "Set Modbus baudrate",
+                                         cmd_modbus_set_baud),
+                               SHELL_CMD(set_id, NULL, "Set Modbus slave ID",
+                                         cmd_modbus_set_id),
+                               SHELL_SUBCMD_SET_END);
 
 SHELL_STATIC_SUBCMD_SET_CREATE(sub_valve_cmds,
-    SHELL_CMD(set_open_time, NULL, "Set max valve opening time", cmd_valve_set_open_time),
-    SHELL_CMD(set_close_time, NULL, "Set max valve closing time", cmd_valve_set_close_time),
-    SHELL_SUBCMD_SET_END
-);
+                               SHELL_CMD(set_open_time, NULL,
+                                         "Set max valve opening time",
+                                         cmd_valve_set_open_time),
+                               SHELL_CMD(set_close_time, NULL,
+                                         "Set max valve closing time",
+                                         cmd_valve_set_close_time),
+                               SHELL_SUBCMD_SET_END);
 
 SHELL_CMD_REGISTER(modbus, &sub_modbus_cmds, "Modbus configuration", NULL);
 SHELL_CMD_REGISTER(valve, &sub_valve_cmds, "Valve configuration", NULL);
-SHELL_CMD_REGISTER(show_config, NULL, "Show all configurations", cmd_config_show);
+SHELL_CMD_REGISTER(show_config, NULL, "Show all configurations",
+                   cmd_config_show);

software/lib/shell_system/shell_system.c

@@ -1,8 +1,26 @@
+/**
+ * @file shell_system.c
+ * @brief Provides basic system-level shell commands.
+ *
+ * This file implements essential system commands for the Zephyr shell,
+ * such as rebooting the device.
+ */
+
 #include <zephyr/shell/shell.h>
 #include <zephyr/sys/reboot.h>
 
-static int cmd_reset(const struct shell *sh, size_t argc, char **argv)
-{
+/**
+ * @brief Shell command to reset the system.
+ *
+ * This command performs a warm reboot of the device after a short delay
+ * to ensure the shell message is printed.
+ *
+ * @param sh The shell instance.
+ * @param argc Argument count.
+ * @param argv Argument values.
+ * @return 0 on success.
+ */
+static int cmd_reset(const struct shell *sh, size_t argc, char **argv) {
   shell_print(sh, "Rebooting system...");
   k_sleep(K_MSEC(100));  // Allow the shell to print the message
   sys_reboot(SYS_REBOOT_WARM);

software/lib/valve/valve.c

@@ -1,9 +1,18 @@
-#include <zephyr/kernel.h>
-#include <zephyr/settings/settings.h>
-#include <zephyr/logging/log.h>
+/**
+ * @file valve.c
+ * @brief Implementation of the motorized valve control library.
+ *
+ * This file contains the logic for controlling a motorized valve using a
+ * VND7050AJ high-side driver. It uses a delayed work item to handle the
+ * safety timeouts for opening and closing operations.
+ */
+
+#include <lib/valve.h>
 #include <zephyr/device.h>
 #include <zephyr/drivers/gpio.h>
-#include <lib/valve.h>
+#include <zephyr/kernel.h>
+#include <zephyr/logging/log.h>
+#include <zephyr/settings/settings.h>
 
 LOG_MODULE_REGISTER(valve, LOG_LEVEL_INF);
 
@@ -20,10 +29,18 @@ static enum valve_state current_state = VALVE_STATE_CLOSED;
 static enum valve_movement current_movement = VALVE_MOVEMENT_IDLE;
 static uint16_t max_opening_time_s = 60;
 static uint16_t max_closing_time_s = 60;
-static struct k_work_delayable valve_work;
+static struct k_work_delayable
+    valve_work;  // Work item for scheduling valve movement timeouts
 
-static void valve_work_handler(struct k_work *work)
-{
+/**
+ * @brief Work handler for valve movement timeouts.
+ *
+ * This function is executed when the valve's movement timer expires.
+ * It stops the motor to prevent damage and updates the valve's state.
+ *
+ * @param work Pointer to the k_work item.
+ */
+static void valve_work_handler(struct k_work *work) {
   gpio_pin_set_dt(&valve_gpios.in0, 0);
   gpio_pin_set_dt(&valve_gpios.in1, 0);
   gpio_pin_set_dt(&valve_gpios.rst, 0);
@@ -37,25 +54,28 @@ static void valve_work_handler(struct k_work *work)
   current_movement = VALVE_MOVEMENT_IDLE;
 }
 
-void valve_init(void)
-{
+void valve_init(void) {
   k_work_init_delayable(&valve_work, valve_work_handler);
-    settings_load_one("valve/max_open_time", &max_opening_time_s, sizeof(max_opening_time_s));
-    settings_load_one("valve/max_close_time", &max_closing_time_s, sizeof(max_closing_time_s));
+  settings_load_one("valve/max_open_time", &max_opening_time_s,
+                    sizeof(max_opening_time_s));
+  settings_load_one("valve/max_close_time", &max_closing_time_s,
+                    sizeof(max_closing_time_s));
 
   gpio_pin_configure_dt(&valve_gpios.in0, GPIO_OUTPUT_INACTIVE);
   gpio_pin_configure_dt(&valve_gpios.in1, GPIO_OUTPUT_INACTIVE);
-    gpio_pin_configure_dt(&valve_gpios.rst, GPIO_OUTPUT_ACTIVE);  // Keep VND7050AJ out of reset
+  gpio_pin_configure_dt(&valve_gpios.rst,
+                        GPIO_OUTPUT_ACTIVE);  // Keep VND7050AJ out of reset
   gpio_pin_configure_dt(&valve_gpios.sen, GPIO_OUTPUT_INACTIVE);
-    gpio_pin_configure_dt(&valve_gpios.s0, GPIO_OUTPUT_INACTIVE);  // S0 select pin - output
-    gpio_pin_configure_dt(&valve_gpios.s1, GPIO_OUTPUT_INACTIVE);  // S1 select pin - output
+  gpio_pin_configure_dt(&valve_gpios.s0,
+                        GPIO_OUTPUT_INACTIVE);  // S0 select pin - output
+  gpio_pin_configure_dt(&valve_gpios.s1,
+                        GPIO_OUTPUT_INACTIVE);  // S1 select pin - output
 
-    LOG_INF("Valve initialized: max_open=%us, max_close=%us", max_opening_time_s, max_closing_time_s);
-}
+  LOG_INF("Valve initialized: max_open=%us, max_close=%us", max_opening_time_s,
+          max_closing_time_s);
 }
 
-void valve_open(void)
-{
+void valve_open(void) {
   if (current_state == VALVE_STATE_CLOSED) {
     gpio_pin_set_dt(&valve_gpios.rst, 1);
     gpio_pin_set_dt(&valve_gpios.in1, 0);
@@ -66,8 +86,7 @@ void valve_open(void)
   }
 }
 
-void valve_close(void)
-{
+void valve_close(void) {
   if (current_state == VALVE_STATE_OPEN) {
     gpio_pin_set_dt(&valve_gpios.rst, 1);
     gpio_pin_set_dt(&valve_gpios.in0, 0);
@@ -77,17 +96,26 @@ void valve_close(void)
   }
 }
 
-void valve_stop(void)
-{
+void valve_stop(void) {
   k_work_cancel_delayable(&valve_work);
   current_movement = VALVE_MOVEMENT_IDLE;
 }
 
 enum valve_state valve_get_state(void) { return current_state; }
 enum valve_movement valve_get_movement(void) { return current_movement; }
-uint16_t valve_get_motor_current(void) { return (current_movement != VALVE_MOVEMENT_IDLE) ? 150 : 10; }
+uint16_t valve_get_motor_current(void) {
+  return (current_movement != VALVE_MOVEMENT_IDLE) ? 150 : 10;
+}
 
-void valve_set_max_open_time(uint16_t seconds) { max_opening_time_s = seconds; settings_save_one("valve/max_open_time", &max_opening_time_s, sizeof(max_opening_time_s)); }
-void valve_set_max_close_time(uint16_t seconds) { max_closing_time_s = seconds; settings_save_one("valve/max_close_time", &max_closing_time_s, sizeof(max_closing_time_s)); }
+void valve_set_max_open_time(uint16_t seconds) {
+  max_opening_time_s = seconds;
+  settings_save_one("valve/max_open_time", &max_opening_time_s,
+                    sizeof(max_opening_time_s));
+}
+void valve_set_max_close_time(uint16_t seconds) {
+  max_closing_time_s = seconds;
+  settings_save_one("valve/max_close_time", &max_closing_time_s,
+                    sizeof(max_closing_time_s));
+}
 uint16_t valve_get_max_open_time(void) { return max_opening_time_s; }
 uint16_t valve_get_max_close_time(void) { return max_closing_time_s; }