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7.4 Serial data output
The transmission of data via the RS485 interface is known as serial data output. Two modes are
available for data transmission:
•
independent transmission of data
•
transmission of data via interrogation telegram
Independent transmission of the data is selected using the command 00TTXX, with XX standing
for the relevant telegram number. In this case the ULTRASONIC transmits its data cyclically in the
repeat rate selected with the parameter OR.
7.4.1 Data enquiry
The command TR is used for data enquiry via the ULTRASONIC. The command has no access
protection. After processing the command the instrument sends back the appropriate response
telegram. The time between the last character in the request telegram and the first character in the
data telegram is < 0.5ms.
The user-defined telegram and the telegrams, as for the definitions described under 7.4.3 'Fixed
telegram formats‘, are available as data telegrams.
7.4.2 Independent telegram output
Independent telegram output is selected using the command TT. After a valid telegram type has
been input, the ULTRASONIC independently transmits the data telegram selected. The
transmission interval is set in ms using the command OR. The telegram is transmitted every 100ms
as standard. If the baud rate selected does not allow the output cycle to be observed (the time for
data transmission is greater than the interval time), it is possible that telegram output cannot be
carried out.
Remark:
Independent telegram output is only possible in full duplex mode.