PROFIBUS Extended Slave Diagnostics

Operator Menu Location: Generic Hardware Operators -> Networking -> PROFIBus

This operator provides access to Profibus Slave Extended Diagnostic Data.
A Profibus slave's extended diagnostic data is an array of bytes appended to a regular reply to the DDLM_Slave_Diag message. The format is prescribed by EN 50 170 Normative Parts section 9.3.1: "Read DP Slave Diagnostic Information".
Octet 7 to 32: Ext_Diag_Data (extendible to 244, see section "Restrictions")
In this area the DP-Slave can enter its specific diagnostic. It is
defined a block structure with one header byte each for the device
related diagnostic and the identifier related diagnostic.
These bytes are exposed via 2 additional pins (one INPUT, one OUTPUT) of the Slave Diagnostic operator:



Methodology:
The extended diagnostic data is accessed similarly to a demultiplexer:
INPUTS:
Ext Diag Byte Select (FLOAT): Selects extended diagnostic data byte to display (0...N-1), where N is the number of extended bytes present.
OUTPUTS:
Ext Diag Data Byte (FLOAT): Outputs value of Extended Diagnostic data byte from the selected array index, above. Returns value of (-1) if index is invalid. See the following table.

When operator "Byte Select" input is "0" (zero) , the operator "Data Byte" output contains the first byte of extended diagnostic data, i.e. octet 7 of that slave's DDLM_Slave_Diag reply message.
Note: Extended diagnostic data is not always available. If no extended data is present (N=0), Data_Byte will be -1. This fact may be used to indicate the presence (or lack) of extended data.


Example schema Fills variable fExtDiagByte with each diagnostic data byte from the configured slave, in ascending order. Resets index at the end of the buffer, indicated by output byte equaling (-1).


Proprties:
Name: A string used to identify the specific operator.