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WRITE_MODBUS_RTU_DATA

This is a structure information to define Modbus RTU write configuration, used for transmitting data to external Modbus slave devices via serial communication (RS-485/RS-232).

BYTE#	Field Name	Data Type	Value	Remarks
0	_szSymbol	char[32]		Symbol name (32-byte identifier)
32	_szttyPort	char[16]		Serial (TTY) port name (e.g., /dev/ttyUSB0, COM3)
48	_iSlaveID	int		Slave device ID (1–255)
52	_iBaudRate	int		Baud rate (e.g., 9600, 115200)
56	_iByteSize	int		Data bits (7 or 8)
60	_szParity	char		Parity (N/E/O)
61	_iStopBit	int		Stop bits (1 or 2)
65	_iRegType	unsigned char		Register type (0: Coil, 1: DI, 2: Holding, 3: Input)
66	_iRegIndex	unsigned short		Register address (index)
68	_iRegValue	unsigned short		Register value (0-65535)

Total size: 72 bytes

Defined in: DRFS.h

typedef struct _WRITE_MODBUS_RTU_DATA
{
    /* symbol name */
    char            _szSymbol[MAX_SYMBOL_SIZE];
    /* tty device */
    char            _szttyPort[16];
    /* Slave ID*/
    int             _iSlaveID;
    /* Baud Rate */
    int             _iBaudRate;
    /* Byte size */
    int             _iByteSize;
    /* Parity */
    char            _szParity;
    /* Stop bit */
    int             _iStopBit;
    /* i/o type */
    unsigned char   _iRegType;
    /* register address */
    unsigned short  _iRegIndex;
    /* register value */
    unsigned short  _iRegValue;

} WRITE_MODBUS_RTU_DATA, *LPWRITE_MODBUS_RTU_DATA;