ProSoft Technology 5204SE-MNET-PDPMV1 - Manual (Page 170)

5204SE-MNET-PDPMV1 ♦ ProLinx Gateway Reference
Modbus TCP/IP to PROFIBUS DP-V1 Pass-Through Master User Manual
Page 170 of 235
ProSoft Technology, Inc.
December 22, 2009
Variable Name Size/Type Description
In -
SlaveDiagnosticData[ ] 200-element
8-bit Byte
Array For detailed breakdown of the data available in this array,
see Get (Extended) Slave Diagnostic Message Structure
(page 198).
The amount and type of extended diagnostic data returned
varies, and depends on the capabilities of the slave
device. Refer to the device manufacturer's documentation
for slave diagnostic information.
In - RDDiagnostActive 1
Single-bit
Boolean
The DFB will set this bit when the Modbus TCP/IP
message has been initiated and is being processed.
In - RDDiagnostError 1
Single-bit
Boolean
The DFB will set this bit when the Modbus TCP/IP
response is not successfully received. When this bit is set,
it indicates your control and sequencing logic should retry
the command.
In -
RDDiagnostSuccess 1
Single-bit
Boolean
The DFB will set this bit when the Modbus TCP/IP
response is successfully received and the PROFIBUS
cyclic input data variables have been updated.
NOTE: The MBP_MSTR function used on the Quantum platform has a lower data transfer limit
than the DATA_EXCH function for the M340 platform. As a result, on the Quantum platform, the
amount of data that can be transferred between a Quantum PAC and the ProLinx Gateway is 200,
8-bit bytes (100, 16-bit words) per message transaction.
This limit is more than enough for most PROFIBUS DP message telegrams. However, there are a
few PROFIBUS messages that could contain more data in the PROFIBUS response than can be
sent to the Quantum processor using the MBP_MSTR funcution for Modbus TCP/IP. It such
cases, the PROFIBUS data is truncated after the first 200-bytes, any PROFIBUS data beyond that
limit will not be sent to the Quantum, and the excess data will be lost.
The performance of this Get Slave Diagnostics mailbox message may be affected by this limitation.
Please consult your device manufacture's documentation to see if any of your PROFIBUS DP
slave devices provide more than 200 bytes of extended diagnostic data in per message.