Modbus RTU - Multi Devices

main/modbus_rtu.h

@@ -0,0 +1,63 @@
+#ifndef MODBUS_RTU_H
+#define MODBUS_RTU_H
+
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#include "driver/uart.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+
+#include "modbus_memory.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define MODBUS_RTU_MAX_ADU_LEN   256
+#define MODBUS_RTU_MAX_DEVICES   16
+
+typedef struct
+{
+    uint8_t unit_id;
+    modbus_memory_t *mem;
+    const char *name;
+} modbus_rtu_device_t;
+
+typedef struct
+{
+    uart_port_t uart_num;
+    uint32_t baud_rate;
+    uint8_t unit_count;
+    modbus_rtu_device_t devices[MODBUS_RTU_MAX_DEVICES];
+} modbus_rtu_ctx_t;
+
+void modbus_rtu_init(modbus_rtu_ctx_t *ctx, uart_port_t uart_num, uint32_t baud_rate);
+
+bool modbus_rtu_add_device(modbus_rtu_ctx_t *ctx,
+                           uint8_t unit_id,
+                           modbus_memory_t *mem,
+                           const char *name);
+
+modbus_rtu_device_t *modbus_rtu_find_device(modbus_rtu_ctx_t *ctx, uint8_t unit_id);
+
+int modbus_rtu_read_frame(modbus_rtu_ctx_t *ctx,
+                          uint8_t *buf,
+                          size_t buf_size,
+                          TickType_t first_byte_timeout);
+
+bool modbus_rtu_process_request(modbus_rtu_ctx_t *ctx,
+                                const uint8_t *req,
+                                size_t req_len,
+                                uint8_t *resp,
+                                size_t resp_size,
+                                size_t *resp_len);
+
+uint16_t modbus_rtu_crc16(const uint8_t *data, size_t len);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* MODBUS_RTU_H */