Added modbus lib and test

software/lib/modbus.c

@@ -0,0 +1,164 @@
+#include "modbus.h"
+#include <zephyr/kernel.h>
+#include <zephyr/sys/util.h>
+#include <zephyr/modbus/modbus.h>
+#include <zephyr/logging/log.h>
+
+// LOG_MODULE_REGISTER(mbc, CONFIG_LOG_DEFAULT_LEVEL);
+LOG_MODULE_REGISTER(mbc, 4); // Set log level to 4 (Debug)
+
+#define MODBUS_NODE DT_COMPAT_GET_ANY_STATUS_OKAY(zephyr_modbus_serial)
+
+static int client_iface;
+
+static struct
+{
+    int level;   // Water level value
+    int minimum; // Minimum value
+    int maximum; // Maximum value
+    int factor; // Factor for unit conversion
+} measurement;
+
+int mb_init_client(void)
+{
+    const char iface_name[] = {DEVICE_DT_NAME(MODBUS_NODE)};
+    client_iface = modbus_iface_get_by_name(iface_name);
+    LOG_DBG("Modbus client interface: %d", client_iface);
+    if (client_iface < 0)
+    {
+        LOG_ERR("Failed to get Modbus interface by name: %s", iface_name);
+        return client_iface;
+    }
+    return modbus_init_client(client_iface, client_param);
+}
+
+int mb_read_holding_registers(int node, uint16_t reg_addr, uint16_t *data, size_t len)
+{
+    return modbus_read_holding_regs(client_iface, node, reg_addr, data, len);
+}
+
+int mb_read()
+{
+    int rc;
+    int16_t data[5] = {0};
+    rc = mb_read_holding_registers(1, 0x0002, data, sizeof(data) / sizeof(data[0]));
+    if (rc < 0)
+    {
+        LOG_ERR("Failed to read holding registers: %d", rc);
+        return rc;
+    }
+    LOG_HEXDUMP_DBG(data, sizeof(data), "Holding Registers Data");
+
+    int unit, decimals;
+    unit = data[0];
+    decimals = data[1];
+    int factor;
+    switch (unit)
+    {
+    case 1: // cm
+        factor = 10;
+        break;
+    case 2: // mm
+        factor = 1;
+        break;
+    default:
+        LOG_ERR("Unknown unit: %d", unit);
+        return -EINVAL;
+    }
+    switch(decimals)
+    {
+    case 0: // no decimals
+        factor /= 1;
+        break;
+    case 1: // one decimal
+        factor /= 10;
+        break;
+    case 2: // two decimals
+        factor /= 100;
+        break;
+    default:
+        LOG_ERR("Unknown decimals: %d", decimals);
+        return -EINVAL;
+    }
+    measurement.factor = factor;
+    measurement.level = data[2] * factor;
+    measurement.minimum = data[3] * factor;
+    measurement.maximum = data[4] * factor; 
+    LOG_DBG("Water level: %dmm, Minimum: %dmm, Maximum: %dmm", 
+            measurement.level, measurement.minimum, measurement.maximum);
+    return 0;
+}
+
+int mb_read_water_level(double *mb_read_water_level)
+{  
+    int rc = mb_read();
+    if (rc < 0)
+    {
+        LOG_ERR("Failed to read water level: %d", rc);
+        return rc;
+    }
+    *mb_read_water_level = (double)measurement.level / 1000.0; // Convert to meters
+
+    return 0;
+}
+
+int mb_read_water_level_mm(int *mb_read_water_level)
+{  
+    int rc = mb_read();
+    if (rc < 0)
+    {
+        LOG_ERR("Failed to read water level: %d", rc);
+        return rc;
+    }
+    *mb_read_water_level = measurement.level;
+
+    return 0;
+}
+
+int mb_read_minimum_mm(int *mb_read_minimum)
+{
+    int rc = mb_read();
+    if (rc < 0)
+    {
+        LOG_ERR("Failed to read water level: %d", rc);
+        return rc;
+    }
+    *mb_read_minimum = measurement.minimum;
+    return 0;
+}
+
+int mb_read_maximum_mm(int *mb_read_maximum)
+{
+    int rc = mb_read();
+    if (rc < 0)
+    {
+        LOG_ERR("Failed to read water level: %d", rc);
+        return rc;
+    }
+    *mb_read_maximum = measurement.maximum;
+    return 0;
+}
+
+int mb_write_minimum_mm(int minimum)
+{
+    int rc = mb_read();
+    if (rc < 0)
+    {
+        LOG_ERR("Failed to read water level: %d", rc);
+        return rc;
+    }
+    modbus_write_holding_reg(client_iface, 1, 0x0005, minimum / measurement.factor);
+    return 0;
+}
+
+int mb_write_maximum_mm(int maximum)
+{
+    int rc = mb_read();
+    if (rc < 0)
+    {
+        LOG_ERR("Failed to read water level: %d", rc);
+        return rc;
+    }
+    modbus_write_holding_reg(client_iface, 1, 0x0006, maximum / measurement.factor);
+    return 0;
+}

software/lib/modbus.h

@@ -0,0 +1,24 @@
+#ifndef __waterlevel_h
+#define __waterlevel_h
+
+#include <zephyr/modbus/modbus.h>
+
+const static struct modbus_iface_param client_param = {
+	.mode = MODBUS_MODE_RTU,
+	.rx_timeout = 50000,
+	.serial = {
+		.baud = 9600,
+		.parity = UART_CFG_PARITY_NONE,
+	},
+};
+
+int mb_init_client(void);
+int mb_read_holding_registers(int node, uint16_t reg_addr, uint16_t *data, size_t len);
+int mb_read_water_level(double *mb_read_water_level);
+int mb_read_water_level_mm(int *mb_read_water_level_mm);
+int mb_read_minimum_mm(int *mb_read_minimum);
+int mb_read_maximum_mm(int *mb_read_maximum);
+int mb_write_minimum_mm(int minimum);
+int mb_write_maximum_mm(int maximum);
+
+#endif