Comtech EF Data CDM-550T Manual page 7

CDM-550T Satellite Modem
7.1 Introduction ................................................................................................................................................7-1
7.2 Viterbi..........................................................................................................................................................7-1
7.3 Sequential ....................................................................................................................................................7-2
7.4 Reed-Solomon Outer Codec (Option) .......................................................................................................7-3
7.5 Turbo Product Codec (Option) .................................................................................................................7-4
7.1.1 End-to-End Processing Delay ..............................................................................................................7-6
7.6 Uncoded Operation (No FEC) ...................................................................................................................7-7
CHAPTER 8. OFFSET QPSK OPERATION .............................................................. 8-1
CHAPTER 9. EIA-232 DATA INTERFACE - ASYNCHRONOUS OPERATION ........ 9-1
9.1 Introduction ................................................................................................................................................9-1
9.2 ASYNC EIA-232 Specifications.................................................................................................................9-1
9.3 Setup ............................................................................................................................................................9-2
9.4 Other Considerations .................................................................................................................................9-2
9.4.1 Baud Rate Accuracy ............................................................................................................................9-2
9.4.2 Async Character Formats Using 1.5 Stop Bits.....................................................................................9-2
CHAPTER 10. CLOCKING....................................................................................... 10-1
10.1 Transmit Clocking ...............................................................................................................................10-1
10.1.1 Internal Clock ................................................................................................................................10-1
10.1.2 External Clock...............................................................................................................................10-1
10.1.3 Loop-Timed, RX=TX....................................................................................................................10-2
10.1.4 Loop-Timed, RX<>TX (Asymmetric Loop Timing) ....................................................................10-2
10.2 Receive Clocking ..................................................................................................................................10-2
10.2.1 Buffer Disabled .............................................................................................................................10-2
10.2.2 Buffer Enabled, RX=TX ...............................................................................................................10-2
10.2.3 Buffer Enabled, RX<>TX .............................................................................................................10-3
10.3 X.21 Notes .............................................................................................................................................10-3
10.4 Loop Timing With Sync EIA-232 .......................................................................................................10-3
CHAPTER 11. EDMAC CHANNEL .......................................................................... 11-1
11.1 Theory Of Operation ...........................................................................................................................11-1
11.2 M&C Connection .................................................................................................................................11-2
11.3 Setup Summary ....................................................................................................................................11-3
Rev.1.3
Preface
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