Telenetics 2185 manual Switch Segment 2-1 Contention Mode

		Telenetics 2185
Table 3-3. Function Switch Two Summary
Function	Switch
Switch	Position	Function
2-7	Up	Sets main channel RTS or DCD transparent
	Down	Straps main channel RTS or DCD ON
2-8	Up	Straps main channel inbound CTS ON
	Down	Sets main channel inbound CTS transparent

In certain synchronous configurations, the internal clock generator is not used and the data rate is determined by the selected external clock source. (For details, refer to the section on function switch segments 2-5 and 2-6 - Clock Routing.) The internal clock generator is also used in asynchronous applications when Data Contention is selected.

Switch Segment 2-1 — Contention Mode

•Switch 2-1 set to up position – Control Signal Contention

•Switch 2-1 set to down position – Data Contention

In applications where the subchannel devices toggle control signals, set this switch to the up position for Control Signal Contention. Where active control signals are not provided, set to the down position for Data Contention. This selects the RTS or DCD control signal for contention, depending on whether the subchannel is configured as a DTE or DCE. When Data Contention mode is selected, switch segments 2-7 and/or 2- 8 must be strapped ON.

Switch Segment 2-2 — Data Format

•Switch 2-2 set to up position – Synchronous format

•Switch 2-2 set to down position – Asynchronous format

Set this switch to the up position for Bisynchronous or HDLC applica- tions (synchronous operation). When set to the down position, (asyn- chronous operation selected), the retiming buffer is bypassed.

Switch Segment 2-3 — Synchronous Data Retiming Buffer

•Switch 2-3 set to up position – Normal

•Switch 2-3 set to down position – Buffer bypassed

When the 2185 is configured for asynchronous data format (function switch 2-2 is set to the down position), that switch may be ignored.

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