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06.91
The following parameters of the 3964R procedure are configurable:
Transmission rate
Priority
Repetitions
Monitoring times
Block length
Acknowledgement delay
3.3.2
LSV2 procedure
This procedure is based on the German DIN standard 66019.
The transmission procedure is an agreement on the data exchange procedure, the operating
mode and other parameters. It ensures reliable transmission of data. LSV2 is an asynchronous
synchronous data transmission procedure (start-stop procedure) for point-to-point connections.
Both stations are authorized to start transmission.
Phases of the procedure
3 phases are possible for the procedure:
EOT
Control characters initiating a change of phase are entered in the phase diagram. With the
transmitting station, the change of phase is caused by transmission of a control character, and
with the receiving station by reception of that character.
The ENQ character also occurs in the enquiry and text transfer phases but does not cause a
change of phase.
Transmission is idle during the basic phase. The station moves to the enquiry phase through a
request to send or when it receives the ENQ character.
In the enquiry phase, the station informs the other station that it wishes to send, where upon
the station at the other end assumes its status as receiving station. In the text transfer phase,
the text is transmitted in the form of a message frame.
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SINUMERIK 840/880 (PJ)
(speed of data transmission)
(master or slave; only valid in the event of a conflict)
(number of repetitions after negative or incorrect
acknowledgement)
(acknowledgement monitoring time for transmitter and character
delay or monitoring time)
(128 bytes or 256 bytes)
(with/without)
Basic phase
ENQ
Enquiry phase
STX
Text transfer phase
6FC5 197-0AB20-0BP0
3 Interface Modules
3.3.1 3964R procedure
EOT
EOT
3–17
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