Optelecom 9525A, Инструкция по установке и эксплуатации

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Optional Switches
ECHO CANCEL, SWITCH #7: In RS232, RS422, or RS485 4-wire modes, when operating as a master in
a fault tolerant ring, the data ECHO may be disabled by setting MODES switch #7 in the DOWN
position.
RS485 LINE TERMINATION, SWITCH #10: If the modem is connected to an RS485 bus, terminate the
input by setting switch #10 in the DOWN position only if it is the terminating unit on the bus.
2.4.4 RS232 Anti-stream Enable/Timeout Selection
To set switch numbers 1 and 2 of the TIMEOUTS dipswitch to disable or select an RS232 anti-
streaming timeout as explained in section 2.3.1, refer to Table 4.
Table 4 – RS232 Antistream Timeout Selection via the Timeouts Dipswitch
Time S2
(seconds) 1 2 3
Disabled Dn Dn Dn
64 Up Dn Dn
32 Dn Up Dn
16 Up Up Dn
8 Dn Dn Up
4 Up Dn Up
2 Dn Up Up
1 Up Up Up
D (DOWN) = ON; U (UP) = OFF
2.4.5 Optical Side Anti-streaming Enable
The optical side anti-streaming feature (see section 2.3.2) can be enabled or disabled via switch
position #4 of the MODES dipswitch. It is disabled when the switch is set in the DOWN position and
enabled when the switch is set in the UP position.
2.4.6 Priority Select Timeout Selection
To select the Priority Select timeout as explained in Section 2.3.3, set TIMEOUTS switch number 5
DOWN for 2.22 ms and UP for 8.88 ms.
To help in the selection consider the following:
1) The Priority Select function is not used when operating in Daisy Chain Mode.
2) The purpose of the Priority Select timeout is to keep the modem output from switching from
one receiver to the other within a data message, between bits, rather than only at the
beginning of a message. To prevent this, select a timeout equal to one whole byte, say 10 bits,
at the operating data rate. For example, at 9600 bps, one bit equals 104 microseconds. Ten
times 104 microseconds equals 1040 microseconds, or about 1millisecond. Select the 2.22 ms
timeout.