modbus_write_registers

 

Function

 

Uses the function code Write Multiple Registers (code 16) to write multiple registers to the holding register area.

 

Format

 

ret = modbus_write_registers( ctx , addr , nb , data )

 

Parameters

 

ctx [ VB.NET： IntPtr ] [ C, C++： modbus_t * ] [ C#： IntPtr ] [ Python： ctypes.c_int ]

Specify the pointer to the libmodbus structure.

 

addr [ VB.NET： Integer ] [ C, C++： int ] [ C#： int ] [ Python： ctypes.c_int ]

Specify the start address to write.

 

nb [ VB.NET： Integer ] [ C, C++： int ] [ C#： int ] [ Python： ctypes.c_int ]

Specify the number of registers to write.

 

data [ VB.NET： Ushort() ] [ C, C++： uint16_t * ] [ C#： ushort[] ] [ Python： ctypes.POINTER(ctypes.c_uint16) ]

Specify the start address of the array that has stored the data to be written.

 

Return values

 

ret [ VB.NET：Integer ] [ C, C++： int ] [ C#： int ] [ Python： ctypes.c_int ]

 

If the function succeeds, the number of registers that were successfully written is returned.

If the function fails, -1 is returned, and the following errno is set.

 

Definition

Description

EMBMDATA

The number of request data is too large.

 

Remarks

 

Uses the function code Write Multiple Registers (code 16) to write multiple registers to the holding register area.

 

Example

 

Writes 0x55 for 8 words from the register at address 0.

 

VB.NET

Dim ret As Integer

Dim ctx As IntPtr

Dim data(8) As Ushort

Dim i As Short

For i = 0 To 7

     data(i) = &H55

Next

ret = modbus_write_registers(ctx, 0, 8, data)

 

C, C++

int ret;

modbus_t *ctx;

Uint16_t status[8];

for( i = 0 ; i < 8 ; i++ ){

     data[i] = 0x55;

}

ret = modbus_write_registers( ctx, 0, 8 , data );

 

C#

int ret;

IntPtr ctx;

ushort data = new ushort[8];

short i;

for( i = 0 ; i < 8 ; i++ ){

     data[i] = 0x55;

}

ret = modbus.WriteRegisters(ctx, 0, 8, data);

 

Python

ret = ctypes.c_int

ctx = ctypes.POINTER(modbus_t)

uint16_buff_type = ctypes.c_uint16 * 8

data = uint16_buff_type()

for i in range(8):

     data[i] = 0x55

ret = modbus.modbus_write_registers(ctx, 0, 8, data)