IBM eserver pSeries 690, User Manual

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Switch Position Function
13 UP 28.8KB Line Speed
14 Up
15 Up CD and DSR Normal Functions
16 Up 2-Wire Leased Line Enabled
* Only switches 11 and 12 are changed from the factory default settings.
Xon/Xoff Modems
Some early modems assume software flow control (Xon/Xoff) between the computer
and the modem. Modems with this design send extra characters during and after the
transmitted data. The service processor cannot accept these extra characters. If your
configuration includes such a modem, your functional results may be unpredictable.
The sample modem configuration files included in this appendix do not support these
modems, so custom configuration files are necessary. Anchor Automation 2400E is an
example of such a modem.
If you experience unexplainable performance problems that may be due to Xon/Xoff
characters, it is recommended that you upgrade your modem.
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 that 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 interrupt on
only the first ring, set Ring Indicate Power-On to start on the first ring. Otherwise, you
can choose to start Ring Indicate Power-On on any ring count.
Terminal Emulators
The service processor is compatible with simple ASCII terminals, and therefore
compatible with most emulators. When a remote session is handed off from the service
processor to the operating system, agreement between 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 that the key
assignments and responses match, ensuring successful communications and control.
For best formatting, choose line wrap in your terminal emulator setup.
Appendix D. Modem Configurations
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