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Write to Coils and Holding Registers in the Modbus Explorer

You can write to coils and holding registers in the Modbus Explorer. This is the functionality of the Modbus write function.

You must first configure your device before performing write or read operations. For information on how to configure and connect to your device, see Configure a Connection in the Modbus Explorer. For more information on performing reads, see Read Coils, Inputs, and Registers in the Modbus Explorer.

Use the Write Registers section of the app to perform write operations.

  1. Enter the information about the register you want to control in the Write Registers section. You can do one write at a time using this section of the app.

  2. To set up the write, click the Address field and enter the address of the register you want to write a value to.

  3. In the Register Type field, click the down arrow to select the register type of the address. You can perform a Modbus write operation on two types of targets: coils and holding registers.

  4. In the Precision field, click the down arrow to select the precision. This is the data format of the register being written to on the Modbus® server.

  5. In the Write Value field, enter the value to write. For coils and inputs, you can only write values of 0 or 1. For input registers and holding registers you can write other values.

  6. Once you have entered all the fields, the Write button becomes activated.

  7. To send the value to the register, click Write.

  8. If you have the same register listed in the Read Registers table, you see the read value update when you click Write. In the example shown here, you can see that the value of 30 was sent to the register and that it is now reflected in the read table for Reg_5 in the first row.

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