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What is the reason of extended diagnostic overflow in Unity PLC on pfofibus when trying to communicate with TEsysT?

Published date: 21 February 2019

On profibus network during initialization , the PLC (master) always ask slaves for diagnostic data (get_diagnostic telegram).
Slave will respond with diagnostic data.
Diagnostic data can cosnist of:
- standard diagnostic or
- standard diagnostic + extended diagnostic
Length of standard diagnostic data is fixed, while extended diagnostic is manufacturer-specific and its content and lenght is defined by manufacturer 
TesysT serve not only standard diagnostic but also extended diagnostic (manufacturer specific). Max length of diagnostic telegram from TEsysT is 36bytes. Description of TEsysT diag telegram is in attachment.
In unity, the profibus modules by default allocate 32bytes for diagnostic telegram which is not enough for TEsysT. Change it to 36 bytes or more.

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