Telenetics 2185 manual Applications, Anti-Streaming

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Telenetics 2185

phase, frequency, and the presence of jitter could cause the subchannel and the main channel to lose synchronization. If synchronization is lost, data errors occur and transmission fails.

When the 2185 is configured for asynchronous operation, the retiming buffer is bypassed.

Anti-Streaming

Anti-streaming protects the network from becoming jammed if one of the subchannel devices fails. If the subchannel remains active for longer than the anti-streaming time-out period, nominally 25 seconds, it auto- matically is disabled and its alarm LED indicator lamp illuminates.

When a subchannel is disabled, it disconnects from the main channel and is not permitted to contend for the main channel again until after it is re-enabled. Before attempting to re-enable the subchannel device, it must be inactive for approximately 1.5 seconds. The alarm LED then extinguishes and the subchannel can again contend for the main chan- nel. You may disable anti-streaming with a front panel switch.

APPLICATIONS

The 2185 is used in multipoint networks made up of a controller and polled terminals. The controller inserts terminal address codes and the terminals must be able to respond to their own address code. The 2185 arbitrates if two or more terminals try to transmit simultaneously.

When considering possible applications for your 2185, remember the following points:

•The 2185 can transmit in either asynchronous or synchronous for- mat, but all devices in the network must use the same format.

•All devices must operate at the same data rate. When the main channel is connected to a DCE device, the transmit and receive clocks may be at different rates, but all devices have common transmit clocks and common receive clocks.

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Contents Telenetics Proprietary Material Page Page Contents Ordering Information Features IntroductionData Interface Subchannel Contention Main Channel BroadcastSynchronous Data Retiming Buffer Anti-Streaming ApplicationsPort-Sharing Application Port-Sharing ModeModem-Sharing Application Modem-Sharing ModeCascading Co-Located TerminalsLocal Cascading Application Remote Cascading Application Specifications SpecificationsTelenetics Site Selection and Preparation Customer ResponsibilitiesPacking Materials UnpackingEquipment Supplied Damage/Material ShortagesEquipment Assembly Installation ProcedureInstallation Tools Required Mechanical InstallationRear Panel Assembly Straight-Through Cable Interface Telenetics Front View Door Closed Operating Controls IndicatorsInside Front Panel Function Switches Function Switch OneEnabling/Disabling Subchannels Function Switch Two Data Rate Selection Using Switch Segments 1-6 toFunction Switch Two Summary Switch Segment 2-1 Contention Mode Clock Routing Configurations Switch Segment 2-4 Anti-Streaming Enable/DisableSwitch Segment 2-7 Main Channel RTS/DCD Strapping External Clock Reference with Main Channel DTE External Clock Reference with Main Channel DCE Internal Clock Reference with Main Channel DTE Internal Clock Reference with Main Channel DCE Subchannel 1 DCE Clock Reference with Main Channel DTE Subchannel 1 DCE Clock Reference with Main Channel DCE Configuration Examples LED IndicatorsFunction Switch Three DTE/DCE OptioningDigital Bridging Application Example Digital Bridging Application Switch Two Switch OneSwitch Three Leased-Line Backup Application Example10 Leased-Line Backup Application Switch One 11. Switch Three 10. Switch Two11. Multimaster Multidrop Application Multimaster Multidrop Application Example12. Switch One Settings 2185 a 13. Switch Two Settings 2185 a 14. Switch Three Settings 2185 a15. Switch One Settings 2185 B 17. Switch Three Settings 2185 B 16. Switch Two Settings 2185 B18. LED Status Indicator Functions Main Power Connection12 Power Connection Operation POWER-DOWN ProcedurePreventive Maintenance Maintenance PhilosophyCorrective Maintenance Recovery from Anti-Streaming Alarm ConditionInstallations in the USA Returning Defective Equipment for RepairGeneral Packing Information Installations Outside the USA or Canada Telenetics Telenetics Ordering Information Ordering InformationTelenetics Glossary Glossary-2 Glossary-3 Glossary-4 Index INDEX-2 INDEX-3 INDEX-4