IBM RS/6000 H50, Installation And Service Manual

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Ring Detection
Most modems produce an interrupt request each time they detect a ring signal.
Some modems generate an interrupt only on the first ring signal they receive. AT&T
DataPort 2001 is an example of such a modem.
The Service Processor uses the ring interrupt request to count the number of rings
when Ring Indicate Power-On (RIPO) is enabled. If your modem produces an inter-
rupt on only the first ring, set Ring Indicate Power-On to start on the first ring. Other-
wise, you may choose to start Ring Indicate Power-On on any ring count that makes
your operation convenient.
Terminal Emulators
The Service Processor is compatible with simple ASCII terminals, and therefore com-
patible with most emulators. It is for the cases when a remote session is handed off
from the Service Processor to the operating system that agreeing terminal emulators
becomes important.
The server's operating system will have some built-in terminal emulators. You may
also have a commercially available terminal emulation. It is important that the local
and host computers select the same or compatible terminal emulators so the key
assignments and responses will match. This will assure successful communications
and control.
For best formatting, choose line wrap in your terminal emulator setup.
Recovery Procedures
Line noises, power surges, etc., can sometimes cause your modem to enter an
undefined state. When it is being used for dial in, dial out or Ring Indicate
Power-On, your modem is initialized each time one of these actions is expected. If
one of these environmental conditions occur after your modem has been initialized, it
may be necessary to recover your modem to a known state.
Appendix C. Modem Configurations
C-5