Beckhoff EtherCAT EL6001, Документация

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Commissioning
EL600x, EL602x 139 Version: 4.6
Fig. 162: Confirming program start
• After the character 0x13 has been received, the barcode is stored in “LastBarcode”
Fig. 163: Received barcode
5.8.2 Sample program 2
https://infosys.beckhoff.com/content/1033/el600x_el602x/Resources/zip/1719192971.zip
Reading and interpreting time telegrams
This example shows a way to process and interpret the most diverse serial time protocols in the PLC. To this
end, IEC61131-PLC blocks will be presented that interpret the bit stream arriving at the PLC and, if
necessary, extract the time/place information. This information can be used, for example, to synchronize
controllers or record movements.
In this example, it is assumed that the data is delivered via a 22-byte interface by a Beckhoff EL/KL60xx
serial data exchange terminal.
Background information
Not only in maritime applications is time and place information transported via serial buses: In the majority of
cases an existing source distributes its information to lower level listeners/listeners cyclically or after a trigger
via RS232 / RS485, USB or Ethernet.
A very large number of telegram formats exists worldwide for the distribution of time and place information;
these are also known as ‘sentences’. Such a telegram consists of n bytes of data and is characterized by:
• Start and end characters STX, ETX for telegram recognition, possibly more than one end character
• a defined and fixed length
• a defined structure
• checksum (not necessary)
• type designations in the sentence if necessary
The most diverse organizations and companies have developed open or proprietary formats for specific
purposes of use. Therefore, two sample implementations will be presented in this example that can easily be
adapted to other specific protocols. The telegram formats in the example are the Meinberg Standard and
NMEA0183 v2.3 type RMC.