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Canoga Perkins
4.4.1 RTS_BIAS Jumper
The RTS_BIAS jumper controls the state that RTS floats to when there is no signal
driving the RTS pin. The OFF position forces this signal to the OFF (negated) state
when the interface cable is disconnected. The ON position forces it to ON (asserted).
Factory Setting = OFF
4.4.2 DCD Jumper
The DCD jumper determines the source of the DCD output. In the CTRL position,
the DCD output functions as the output for the RTS input at the far end. In the CD
jumper position, the DCD output will turn ON either when the modem’s fiber optic
receiver is in sync (main board internal switch S1 CD / DCD = OFF and CD / SYNC
= ON)
or
when the far end RTS is ON (main board switch S1 CD / DCD = ON and
CD / SYNC = OFF). Refer to Section 2.2.1 for more information on the internal
switch S1 CD / DCD and CD / SYNC positions.
Factory Setting = CTRL
4.4.3 DSR Jumper
The DSR jumper controls the behavior of the DSR signal. The EIA position turns
DSR OFF when the far end 2240 has a local loopback active. The TEST position
causes DSR to turn OFF whenever any loopback is active at one or both of the
modems.
Factory Setting = TEST
4.4.4 CHASSIS_GND Jumper
The jumper selects whether chassis ground is connected directly to signal ground
(SHORT position) or through a 100 Ohm resistor (100_OHM position).
NOTE: In the standalone model, the 100_OHM position only puts a
100 Ohm resistor between the two grounds if the 2240's main board
SIGNAL GND jumper is set to the FLOAT position.
When installed in the 2201 Rack Chassis, any modem main board,
interface or rack chassis jumper being set to SHORT will override the
FLOAT and 100_OHM positions on all of the other modems.
CONSIDER THIS JUMPER CAREFULLY.
Factory Setting = 100_OHM
Содержание 2240
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Страница 4: ...4 Canoga Perkins Model 2240 Fiber Optic Modem...
Страница 15: ...2240 Fiber Optic Modem 15 Figure 1 4 2240 Functional Block Diagram...
Страница 34: ...34 Canoga Perkins Table 3 E Standard Oscillator and Divide Factors...
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Страница 92: ...92 Canoga Perkins Table 4 V Models D22 and D88 Connector Pin Assignments...