Operation; Translating Sector Information; Fixed Translation Mode; Universal Translation Mode - RadiSys EXM-9 Reference

3. Operation

This chapter discusses the main setup and connectors of the EXM-9.
In addition to configuring the EXM-9 using the EXM Setup Screen, you will also
need to describe your connected disk configuration on the main setup screen. If you
have a floppy drive connected and enabled, select the diskette drive A option that
matches your floppy drive. If you have an IDE drive connected and enabled, enter
the fixed-disk menu, select "AT" as the type for fixed disk C, and then select a
numeric type that matches the characteristics of your drive.

Translating Sector Information

To select the correct IDE drive type number, you must first determine how your disk
drive translates sector information. There are two common modes: fixed translation
mode and universal translation mode.

Fixed Translation Mode

If your drive uses fixed translation mode, you must select a drive type with the exact
number of sectors per track and heads per cylinder as specified by the drive's manu-
facturer. What doesn't need to be exact is the number of cylinders. Find an entry on
the BIOS fixed-disk menu that matches the number of sectors per track and heads per
cylinder and whose number of cylinders is less than or equal to your actual drive.
Typically this will be in the range of AT drive types 1-23.

Universal Translation Mode

If your drive uses the universal translation mode, you do not have to use the exact
physical parameters of the drive. Instead, you may follow this procedure:
1. Determine the total number of blocks (sectors) on your drive. Call this
value B. If this is not specified directly by the manufacturer, it can be
computed as the number of cylinders times the number of heads times
the sectors per track.
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