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Modbus TCP/IP Client Write

Client device writes data to server device register(s) over TCP/IP network

Since R2021a

Add-On Required: This feature requires the Simulink Support Package for Raspberry Pi Hardware add-on.

  • Raspberry Pi MODBUS TCP/IP Client Write icon

Libraries:
Simulink Support Package for Raspberry Pi Hardware / Network

Description

In the Modbus TCP/IP Client Write block, the client device writes data to the register(s) of the server device.

Simulink® Support Package for Raspberry Pi® Hardware supports the Modbus® communication protocol over the TCP/IP network. The client and the server must be connected to the TCP/IP network for successful Modbus communication.

The client can perform either a read, write, or a read and write operation on the server register depending on the server register(s) type.

Register TypeRegister SizeOperation Performed by Client
Coil1-bitRead and Write
Discrete Input1-bitRead
Holding Register16-bitRead and Write
Input Register16-bitRead

The client can perform either a read or a write operation (depending on the register type) on register(s) of a server device.

Ports

Input

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The input to the block is the data that the client writes to the server register(s). Specify the input data as a N-by-1 vector, where N represents the number of registers on the server device.

  • If you select the Coil or Discrete Input write operations, the client writes data to the server registers as a 1-bit write operation as Boolean data.

  • If you select the Holding Register or Input Register write operations, the client writes data to the server registers as a 16-bit write operation as uint16 data.

Data Types: Boolean | uint16

Parameters

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Enter the IP address of the server device to identify the server to which the client writes the data.

Select the type of write operation you want to perform on the server register(s). Specify any one of the following:

  • Write Coil: Write data to the coil register address specified in the Coil Address parameter.

  • Write Holding register: Write data to the holding register address specified in the Holding Register Address parameter.

  • Write Multiple Coils: Write data to multiple coil registers depending on the values specified in the Coil Address and Number of Coils parameters.

  • Write Multiple Holding registers: Write data to multiple holding registers depending on the values specified in the Holding Register Address and Number of Holding registers parameters.

  • To notify the client to write data to a specific coil register, specify the coil register address in this parameter. For example, for the client to write data to the coil register with the address 10, enter 10.

  • To notify the client to write data to a group of coil registers, specify the address of the first coil register in the group. For example, for the client to write data to the coil registers with addresses ranging from 10 to 14, enter 10.

Dependencies

To enable this parameter, set Function to Write Coil.

Enter the number of coil registers to which you want the client to write the data. For example, for the client to write data to the coil registers with addresses ranging from 10 to 14, enter 5.

Dependencies

To enable this parameter, set Function to Write Multiple Coils.

  • To notify the client to write data to a specific holding register, specify the holding register address in this parameter. For example, for the client to write data to the holding register with the address 37, enter 37.

  • To notify the client to write data to a group of holding registers, specify the address of the first holding register in the group. For example, for the client to write data to the holding registers with addresses ranging from 37 to 44, enter 37.

Dependencies

To enable this parameter, set Function to Write Holding register.

Enter the number of holding registers from which you want the client to write the data. For example, for the client to write data to the holding registers with addresses ranging from 37 to 44, enter 8.

Dependencies

To enable this parameter, set Function to Write Multiple Holding registers.

Version History

Introduced in R2021a