User`s guide

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Chapter 4: Solving Problems
74 Test real-time clock
76 Check for keyboard errors
7A Test for key lock on
74 Test real-time clock
76 Check for keyboard errors
7A Test for key lock on
7C Set up hardware interrupt vectors
7E Test coprocessor if present
80 Detect and install external RS-232 ports
82 Detect and install external parallel ports
85 Initialize PC-compatible PnP ISA devices
86 Re-initialize on board I/O ports
88 Initialize BIOS Data Area
8A Initialize Extended BIOS Data Area
8C Initialize floppy controller
90 Initialize hard disk controller
91 Initialize local bus hard disk controller
92 Jump to UserPatch2
93 Build MPTABLE for multi-processor boards
94 Disable A20 address line
95 Install CD-ROM for boot
96 Clear huge ES segment register
98 1-2 Search for option ROMs. One long, two short beeps on
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Table 4-1 (continued) Port-80 Codes
Normal Port 80
Codes
Beeps Error