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Xylem Expert 7060_7070_Modbus User Manual

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Communication protocol Serie30

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5.7

Function 66 : Write and read new device address

Request:

DevAddr 66

NewAddr

CRC16_H CRC16_L

Response:

DevAddr 66

ActAddr

CRC16_H CRC16_L

Exception error:

3

If message length is incorrect

32

If device is not yet initialised

Note:

This function programmes the device addresses to NewAddr. The address is returned in ActAddr as confirmation. It is to be

ensured that the new address NewAddr is not already in use by another bus user.

Permissible addresses: 1 .. 249. Address 250 is transparent. This means that every device, irrespective of the set address, will

respond to address 250. Consequently, transparent DevAddr = 250 may only be used in stand-alone operating mode!

For the purpose of reading the device address when the address is not known, for example, the value 250 is transferred as

DevAddr and the value 0 is transferred as NewAddr. The current address is then returned in response.

5.8

Function 69 : Read serial number

Request:

DevAddr 69

CRC16_H CRC16_L

Response:

DevAddr 69

SN3

SN2

SN1

SN0

CRC16_H CRC16_L

Exception errors:

3

If message length is incorrect

32

If device is not yet initialised.

Note:

The serial number is allocated at the factory. It consists of 4 bytes and is calculated as follows :

SN = 256

3

* SN3 + 256

2

* SN2 + 256 * SN1 + SN0