Problems When Booting from the A: Drive
Ifyouencounterproblemswithattemptingtobootfromafloppydisk,checkthefollowing: Diskette media The diskette may not be a bootable disk, which means it does
not contain the system files needed to boot the system. Use the SYS A: command
to copy the system boot files to the diskette.
CMOS settings The boot device setting in CMOS may not be configured with
the floppy disk drive as the first boot disk or it may not be listed as a boot device
at all. Enter the Setup program and change the boot disk sequence or add the
floppy disk drive to the boot device list.
Drive problems A very common problem is that during work inside the
system case, a drive’s power supply connector or data cable becomes partially
disconnected, which results in intermittent errors. Typically, this would be
caught during the POST process, but it can show up in operation as well.Floppy Disk Drive Failures
If the POST process signals a floppy disk drive is bad or missing with either a beep code
ora600-serieserrormessage(seeTable24-1earlierinthechapter),theproblemcouldbea
general failure of the floppy disk drive. Here are some things to check out: Power connector Verify that the power supply connector on the floppy disk
drive is snuggly connected. Also check that the cables in the connector are not
loose, frayed, bent, or crimped. Try using a different power supply connector
or checking the connector’s voltage with a multimeter. If the power in the cable
is not correct, the problem is the power supply.
Cabling It is easy to install the data cable with the wrong alignment or to
shift it one or more pins off. The cable should have a red or blue stripe down
the edge of the cable to indicate Pin 1. If the cable is installed backwards or
incorrectly, the floppy disk drive’s LED will light during the boot and stay lit
solid all the time.
Installing two floppy drives As a general rule, the A: drive (first floppy disk
drive) is installed after (behind) the twist in the cable, and the B: drive (second
floppy disk drive) is installed before (ahead) of the twist in the cable. Figure 24-1
illustrates a floppy disk data cable. The floppy disk drives may have a jumper
to configure it for the twist or without the twist. Check the cable and the drives
against the drives’ documentation.
CMOS The floppy disk controller (FDC) may be disabled in the CMOS setup
data. Verify that the controller is enabled. Also check that the CMOS has the
correct drive types indicated for the A: and B: drives.
Resource conflicts Floppy disk resource conflicts are very rare, since
virtually every PC system reserves IRQ6 and DMA channel 2 for the floppy(^628) PC Hardware: A Beginner’s Guide