Alpha CFR 5000, Operator'S Manual

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4 Communication
54
Alpha Technologies
Step 3: Initalize the Modem
To initalize the modem start a CFR self test (Section 3.3).
The CFR must initialize the modem. If a remote host calls before initialization, the CFR/
modem combination will not answer the call.
TIP: If the modem is set for auto answer and a call is answered before the CFR
initalizes it, the modem uses its own baud rate which may not be the 1200 baud
used by the CFR. In this case the CFR cannot talk to the modem.
The modem must be set for No Answer . When the CFR initalizes the modem, it
automatically sets the RS–232 rate to 1200 baud.
The CFR automatically sends out the initialization string (Item #527):
• One minute after CFR power up and then every hour after.
• At the start of a self test.
•
Before sending out the first automatic alarm.
• Every two minutes after a failed modem command (dial, hang or initialize).
• After starting one of the modem options.
This guarantees the modem is initialized before sending out the first automatic alarm.
If initalization fails, the CFR assumes the modem is on line, sends an escape sequence,
resets the modem and then resends the initalization string. This will not work if the modem is
using a different baud rate than the CFR’s. If this fails, the CFR sends the initialization se-
quence every two minutes until initalization is successful.
Step 4: Accessing the RS–232 Menus (If Used)
Enabling the remote access feature (Item #521) allows you to call the CFR to have access to
all RS–232 menus. The auto answer command (ATSO=1) is sent to the modem during
initalization.
If a call is in progress and no RS–232 commands are received for longer than the remote
hang up time (Item #528) the CFR tells the modem to disconnect from the host. This stops a
faulty host from tieing up the phone line and preventing other calls from being received or
alarms from being sent out.
Modem Installation Finished
4.7 Installing and Using the External Modem (Continued)