BW Broadcast rds2+, Technical Manual

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BW Broadcast Technical Manual
Page 20
Further Features
2.7.1 Additional Information
This additional information provides all details required for implementation of the RDS2+ protocol into your
application (broadcast automation system, messaging system, TMC data source etc.).
Please see also the Annex 1 - Communication Protocol Implementation Flowcharts. Some source code examples are
provided on the website.
2.7.2 Unidirectional or bidirectional – What is the difference?
The RDS2+ supports both unidirectional and bidirectional communication modes. Nothing is required to be set, the
mode of operation results only from the method of communication.
2.7.3 Command synchronization
Unidirectional communication:
If sending more commands in sequence, the execution times must be taken into consideration. In other case some
commands may be discarded after internal buffer filling (the RX buffer length is 48 bytes).
The times result from the EEPROM write cycle duration or from the requirement of internal synchronization with
RDS data group order. Most of commands require no perceptible delay due to internal RX line buffering.
Bidirectional communication:
Next command can be sent after receiving confirm sequence from previous command. This ensures right timing
and optimal channel usage in all cases. There is no need to consider any timing or delays.
2.7.4 Useful notes
• ASCII char. 9 (TAB) is converted to char. 32 (space).
• In addition to the <Enter> (char. 13, CR) used for command validating, character 26 (EOF) can be used. This allows to
insert the validating character on platforms where char. 13 (CR) is not accepted.
• The command interpreter ignores other characters in ASCII range 0-31.
• Space characters (char. 32) are ignored if typed behind validating character on a new line. In this case, the space
characters may be used to realize a delay between two commands.
• The COM port time-out is 2 minutes. If no character is received during this time, the command line is internally cleared.