Patton electronic 2500RC, 2520RC, 2510RC Switches S2-1, S2-2 and S2-3 Rate Adapter/DTE Rate

Switches S2-1, S2-2 and S2-3: Rate Adapter/DTE Rate

The Model 2500RC Series includes a rate adapter that allows the unit to be used with DTE devices that support rates lower than 56/64 kbps. All switch settings below are valid for line rates of 56 or 64 kbps.

S2-1	S2-2	S2-3	DTE Rate
On	On	On	2.4 kbps
Off	On	On	4.8 kbps
On	Off	On	9.6 kbps
Off	Off	On	19.2 kbps
On	On	Off	38.4 kbps
Off	Off	Off	Line Rate = DTE Rate

NOTE: for DTE devices that operate at 57.6 kbps, set the Line Rate to 56 kbps (see Section 3.1.1 4.1.1), set the rate adapter for “Line Rate=DTE Rate”, and configure your DTE device for two stop bits (set character length accordingly).

Switch S2-4: DTE Loop Control

The local loop and remote loop can be activated from the DTE interface using signals “LL” and “RL”.

S2-4

On Enable LL and RL inputs

Off Disable

Switches S2-5 and S2-6: Clock Mode

The appropriate transmitter clocking modes can be selected for Dedicated DDS, Switched-56 or campus-area (private) operation.

S2-5	S2-6	Mode	Description
On	Off	External Clock Mode	Transmit Clock
			derived from terminal
			interface
Off	Off	Network Clock Mode	Transmit clock derived
		(Looped Clock Mode)	from the received line
			signal; Use this mode
			for Dedicated DDS
			operation
On	On	Internal Clock Mode	Transmit Clock
			derived internally
Off	On	Switched 56	(Model 2510, 2520)

Switch S2-7: Anti-Stream Timer

The anti-stream timer protects multidrop networks from a drop that is continuously transmitting. If the terminal keeps RTS raised for more than 30 seconds, the timer forces RTS off internally. This allows the rest of the multidrop network to resume operation. The CSU/DSU remains in the forced-off condition until the terminal drops RTS.

		Timer Value in Sec at Various Line Rates
S2-7	Timer	56	19.2	9.6	4.8	2.4
On	Disabled
Off	Enabled	2	4	8	15	30

Switch S2-8: RTS/CTS Delay

The RTS/CTS turn-on delay can be set to Normal or Extended.

		Delay in mSec at Various Line Rates
S2-8	CTS Delay	56	19.2	9.6	4.8	2.4
Off	Normal	0.3	0.9	1.9	3.8	7.5
On	Extended	1.3	3.8	7.5	15	30

3.1.3 Setting the Reversible Interface Driver Board

The Model 2500RC Series supports both RS-232 and V.35 electrical interfaces for the terminal connection port. Which electrical interface is active is determined by the orientation of the small reversible daughter board on the front card (see Figure 3, below). The daughter board is clearly marked “THIS SIDE UP FOR RS-232”and “THIS SIDE UP FOR V.35”. Note: When plugging the daughter board into the socket, the arrow should always point toward the front of the PC board.

	8
	7
	6
	5
	4	Interface
	3
ON	1 2	Driver
	6 7 8	Board
	5
	4
	3
ON	1 2
	FRONT	THIS SIDE UP FOR V.35

Figure 3. Closeup of Model 2500RC Interface Driver Board

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