Sample MSTR Block - Compressed Timestamping

The diagram below summarizes the use of the MSTR block to send unsolicited data with compressed timestamping to the CIMPLICITY Modbus TCP/IP communication enabler from a device.

In this example:

The Control Block, found in Holding Registers 40100 through 40108, contains control information for the MSTR block. These indicate that nine registers worth of data will be sent to the device at IP address 192.1687.0.57 and stored starting at address 40001.

The CIMPLICITY Modbus TCP/IP Device Communications Enabler does not use address information configured in the control block. Instead, it interprets the data area as a command.

The Data Block, found in Holding Registers 40200 through 40208, contains a command to the CIMPLICITY Modbus TCP/IP communications enabler to set the value of a point at Input Register 17 to a value of 21035 with a compressed timestamp.

More information

Control Block with Compressed Timestamping.

Data Area with Compressed Timestamping.

Modbus TCP/IP Unsolicited Data.