# Write operations

### Read Write Multiple Holding Register <a href="#read-write-multiple-holding-register" id="read-write-multiple-holding-register"></a>

Read Write Multiple Holding Register

#### Parameters <a href="#parameters" id="parameters"></a>

| Parameter                             | Description                                                                                                  |
| ------------------------------------- | ------------------------------------------------------------------------------------------------------------ |
| First Address to be read              | Address from where the data read begins.                                                                     |
| Number of addresses to be read        | Length of data.                                                                                              |
| Slave Address / Unit identifier       | Unit identifier (previously slave address). In asynchonous mode this unit is given to the callback function. |
| First address to be written           | Length of data.                                                                                              |
| Holding register inputs to be written | Contains the register information.                                                                           |

#### Output <a href="#output" id="output"></a>

Return table with values.

#### Since <a href="#since" id="since"></a>

6.4

### Write Multiple Coils <a href="#write-multiple-coils" id="write-multiple-coils"></a>

Write Multiple Coils

#### Parameters <a href="#parameters" id="parameters"></a>

| Parameter                       | Description                                                                                                  |
| ------------------------------- | ------------------------------------------------------------------------------------------------------------ |
| First Address to be written     | Address from where the data written begins.                                                                  |
| Number of addresses to be set.  | Values to be set.                                                                                            |
| Slave Address / Unit identifier | Unit identifier (previously slave address). In asynchonous mode this unit is given to the callback function. |

#### Output <a href="#output" id="output"></a>

No return!

#### Since <a href="#since" id="since"></a>

6.4

### Write Multiple Registers <a href="#write-multiple-registers" id="write-multiple-registers"></a>

Write Multiple Registers

#### Parameters <a href="#parameters" id="parameters"></a>

| Parameter                       | Description                                                                                                  |
| ------------------------------- | ------------------------------------------------------------------------------------------------------------ |
| First Address to be written     | Address from where the data read begins.                                                                     |
| Number of addresses to be read  | Values to write.                                                                                             |
| Slave Address / Unit identifier | Unit identifier (previously slave address). In asynchonous mode this unit is given to the callback function. |

#### Output <a href="#output" id="output"></a>

No return!

#### Since <a href="#since" id="since"></a>

6.4

### Write Coil <a href="#write-coil" id="write-coil"></a>

Write Coil

#### Parameters <a href="#parameters" id="parameters"></a>

| Parameter                       | Description                                                                                                  |
| ------------------------------- | ------------------------------------------------------------------------------------------------------------ |
| First Address to be written     | Address from where the data read begins.                                                                     |
| Number of addresses to be read  | Length of data.                                                                                              |
| Slave Address / Unit identifier | Unit identifier (previously slave address). In asynchonous mode this unit is given to the callback function. |

#### Output <a href="#output" id="output"></a>

No return!

#### Since <a href="#since" id="since"></a>

6.4

### Write Single Register <a href="#write-single-register" id="write-single-register"></a>

Write Single Register

#### Parameters <a href="#parameters" id="parameters"></a>

| Parameter                             | Description                                                                                                  |
| ------------------------------------- | ------------------------------------------------------------------------------------------------------------ |
| First Address to be written           | Address from where the data written begins.                                                                  |
| Holding register input to be written. | Value to write on the address.                                                                               |
| Slave Address / Unit identifier       | Unit identifier (previously slave address). In asynchonous mode this unit is given to the callback function. |

#### Output <a href="#output" id="output"></a>

No return!

#### Since <a href="#since" id="since"></a>

6.4


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