DEUTSCHMANN AUTOMATION UNIGATE CX C4Map, Инструкция по эксплуатации

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28.9.20 Fieldbus-Gateway UNIGATE
®
CX C4Map - PROFIBUS V. 1.0 21
Deutschmann Automation GmbH & Co. KG Implemented protocols in UNIGATE® CX C4Map
7.1.2.14 Start phase
The UNIGATE
®
sends the NMT command "BusStart" every 2 seconds during the start phase; i.e.
all connected CANopen
®
slaves are set to the "Operational" state.
As soon as the UNIGATE
®
has received the first PDO that is present in the mapping, this start
phase is exited; i.e. the NMT command is no longer sent.
There is no timeout here because the CANopen
®
slaves do not have to react to this NMT com-
mand.
If a CANopen
®
slave is later connected to the network, it no longer receives this NMT command.
However, it can be triggered again at any time via the FB command byte (bit 6) in order to also
set later CANopen
®
slaves to the "Operational" state.
7.1.2.15 Data throughput time
Processing times of the data through the gateway:
The actual throughput time of the data from CANopen
®
to the fieldbus or vice versa depends,
among other things, on the following parameters:
• Number of mappings
• Length of the configured PROFIBUS data
• Number of COB IDs used in the mappings
• Number of changed PROFIBUS data between 2 transmissions
• Number of bytes mapped in a COB ID
• Baud rate in PROFIBUS or CAN
Due to these many parameters and the interdependencies of the parameters, no calculation for-
mula for the lead time can be specified. From practical measurements, lead times from 10 ms to
100 ms were observed, the maximum time being measured with a PB configuration of 244 bytes
I / O and 488 mappings.
In practice, under "normal" conditions, a lead time of a few milliseconds can be expected. To opti-
mize the lead time, the following guidelines should be followed:
• Number of mappings as small as possible
• Length of the fieldbus configuration as short as possible
• Use all 8 bytes in the COB-IDs if possible => use as few COB-IDs as possible