> For the complete documentation index, see [llms.txt](https://inacks.gitbook.io/is4310-wiki/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://inacks.gitbook.io/is4310-wiki/datasheet/i2c-compatible-bus-description/multiple-word-write.md).

# Multiple Word Write

> This page is not the authoritative source for design information. The official [IS4310 datasheet](https://www.inacks.com/is4310) published on [www.inacks.com](http://www.inacks.com) is the authoritative reference: always consult it for the latest information.

A Multiple Word Write performs a similar operation to a Single Word Write, but instead of writing to only one register, it can write to a block of up to 500 registers in a single operation.

To perform a Multiple Word Write, follow the same procedure as for a Single Word Write until the first data word is received. After receiving the first word, instead of generating a Stop Condition, the Microcontroller should continue sending data words. To conclude the write operation, after sending the last data word, the Microcontroller should generate a Stop Condition.

With each word written, the Pointer Register increments by one.

After the Stop Condition, if any of the Modbus Configuration Registers (MBADR, MBBDR, MBPAR, MBSTP) are written with a value different from the previous one, a 25 millisecond Flash Memory write cycle will begin.

**Invalid Memory Addressing**

The valid memory range of the IS4310 goes from addresses 0 to 503.

If a Write Operation is performed with a Pointer Register within the valid memory range (0 to 503) but exceeds the last memory register (503), a rollover to position 0 will occur. For example, writing a value to register 504 will result in writing the value to register 0.

If a Write Operation is performed with a Pointer Register higher than 503, the IS4310 will answer with a NACK on the first received byte of the word.

(Click to enlarge)

<figure><img src="https://3728520580-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FsqF9AC2WATFaFsPXv5oP%2Fuploads%2FGMYlunWa2clvBOJgljjg%2Fimage.png?alt=media&amp;token=13e64ad6-2d2c-4e78-b42e-ab2bae76c4df" alt=""><figcaption></figcaption></figure>