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WRITE_MODBUS_MULTI_DATA

This structure defines a Modbus TCP multi-register write request, including the target address, slave information, register start index, and count.

BYTE#

Field Name

Data Type

Value

Remarks

0

_szSymbol

char[MAX_SYMBOL_SIZE]

Symbol name

32

_szIpAddr

char[16]

IPv4 string (null-terminated)

48

_iPort

unsigned short

TCP port

50

_iSlaveID

int

Slave ID

54

_iRegType

unsigned char

Register type

55

_iRegIndex

unsigned short

Start register address

57

_iRegCount

unsigned char

Number of registers

Total size: 58 bytes

Defined in: DRFS.h

typedef struct _WRITE_MODBUS_MULTI_DATA
{
    /* symbol name */
    char                        _szSymbol[MAX_SYMBOL_SIZE];
    /* tcp address */
    char                        _szIpAddr[16];
    /* tcp port */
    unsigned short              _iPort;
    /* Slave ID*/
    int                         _iSlaveID;
    /* i/o type */
    unsigned char               _iRegType;
    /* register start address */
    unsigned short              _iRegIndex;
    /* register count */
    unsigned char               _iRegCount;

} WRITE_MODBUS_MULTI_DATA, *LPWRITE_MODBUS_MULTI_DATA;

typedef WRITE_MODBUS_MULTI_DATA
     WRITE_MODBUS_TCP_MULTI_DATA, *LPWRITE_MODBUS_TCP_MULTI_DATA;