IBM 300 Series 6268, Hardware Maintenance Manual

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Software-generated error messages are displayed if
a problem or conflict is found by an application
program, the operating system, or both. For an
explanation of these messages, refer to the
information supplied with the installed software
package. Also, refer to “Software considerations.”
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Multiple messages occur when the first error causes
additional errors. Follow the suggested action of the
first error displayed.
Software considerations
Suspect a software failure if:
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Hardware diagnostics run error-free.
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Swapping hardware components fails to isolate the
problem.
A software problem might be the result of a mismatch
between the hardware and the operating system
device drivers or direct drivers.
BIOS:
The BIOS acts as an interface between the
system hardware, application software, and the
operating system.
BIOS contains the instructions to operate the basic system
components:
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Keyboard
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Serial and parallel ports
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Diskette drive
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Hard disk drive
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VGA display
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Clock
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Memory controller
The BIOS then starts the IPL or Boot functions.
Drivers:
Device drivers are the BIOS for additional
hardware. Device drivers are the communicators of the
hardware assignments to the operating system, including:
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IRQ level
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DMA channel
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I/O address
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ROM or RAM
Some device drivers like HIMEM.SYS are position
sensitive and must be placed before other device drivers in
the CONFIG.SYS file.
All device drivers are not found in the CONFIG.SYS file.
Advanced operating systems use .INI files to setup and
start devices.
Device drivers can access the hardware five ways.
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Operating system direct to hardware using a
direct driver. Direct drivers, which bypass BIOS,
Related Service Information
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