Multiple Word Write

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.

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