1 files changed, 48 insertions, 0 deletions
diff --git a/src/modbus.h b/src/modbus.h
new file mode 100644
index 0000000..32ca596
--- /dev/null
+++ b/src/modbus.h
@@ -0,0 +1,48 @@
+#ifndef _MODBUS_H
+#define _MODBUS_H
+
+#include "stm32f1xx_hal.h"
+#include "string.h"
+
+#define read_holding_regs  0x03
+#define read_input_regs    0x04
+#define write_single_reg   0x06
+
+#define lowByte(w) ((uint8_t) ((w) & 0xff))
+#define highByte(w) ((uint8_t) ((w) >> 8))
+#define word(h, l) ((h << 8) | l)
+
+#define MODBUS_TIMEOUT 50
+#define MAX_BUFSIZE    64
+
+typedef struct {
+    uint8_t              slave_id;
+    uint16_t             response_buffer[MAX_BUFSIZE];
+    uint8_t              rbuf_len;
+    UART_HandleTypeDef   modbus_uart;    
+} modbus_slave_device;
+
+typedef enum {
+    MB_OK             =  0x0,
+    MB_SLAVE_ID_ERR   =  0x1,
+    MB_FUNC_ERR       =  0x2,
+    MB_CRC_ERR        =  0x3,
+    MB_UART_ERR       =  0x4,
+    MB_BUSY_ERR       =  0x5,
+    MB_TIMEOUT_ERR    =  0x6
+} MB_StatusTypeDef;
+
+
+uint16_t crc16_update(uint16_t crc, uint8_t a);
+MB_StatusTypeDef modbus_transaction (uint8_t func, modbus_slave_device *device,
+				     uint16_t rw_addr, int read_num,
+				     uint16_t write_value);
+MB_StatusTypeDef ReadHoldingRegisters(modbus_slave_device *device, uint16_t reg_addr,
+				      int read_num);
+MB_StatusTypeDef ReadInputRegisters(modbus_slave_device *device, uint16_t reg_addr,
+				    int read_num);
+MB_StatusTypeDef WriteSingleRegister(modbus_slave_device *device, uint16_t reg_addr,
+				     uint16_t write_val);
+void ClearResponseBuffer(modbus_slave_device *device);
+
+#endif