Multitech MT56DSU-R, Owner'S Manual

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Chapter 3 - Operation
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3.2.3 Anti-Streaming
This option is typically enabled on remote DSUs using multi-point
lines. When enabled, the anti-streaming feature prevents a
streaming (“jammed”) DTE from affecting the communications from
remote sites(in a multi-point circuit) that are operating properly.
When Anti-Streaming is enabled, the MT56DSU-R will detect when
the DTE device holds RTS (Request To Send) on for longer than 20
seconds. The MT56DSU-R then forces RTS and CTS off internally
and sends the DDS Idle Channel signal to the network. The DTE’s
interface is ignored until the streaming DTE is repaired. The RTS
LED is continuously lit and the CTS LED is off when a streaming
DTE has been detected.
The default for this function is Anti-Streaming disabled. (Refer to
Chapter 2 for changing the default DIP switch settings.)
3.2.4 Elastic Store
This function allows the MT56DSU-R to compensate for small timing
phase “drifts” that occur in applications using analog modems for
off-net (non-DDS) extensions. An analog off-net extension
application is described in Appendix A. This option should be
enabled on all MT56DSU-Rs that are connected to analog modems.
Notes for off-net (elastic store enabled) sites:
• a special DCE-DCE cross-over cable is required (not supplied
by Multi-Tech).
• the modem located with the MT56DSU-R must be set for
external timing. The modem located at the far end of the off-net
extension must be set for slave timing.
• with applications using controlled carrier, the CTS delay of the
far-end modem of the off-net extension must be set for a longer
period than the MT56DSU-R’s CTS delay time.
The default for this function is Elastic Store disabled. (Refer to
Chapter 2 for changing the default DIP switch settings.)
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