Second Edition now available!Knowing about the key hardware elements of a PC allows applications programmers to dramatically speed up the execution time of their programs. The Undocumented PC reveals for the first time the undocumented or difficult-to-find programming features of critical PC hardware. In addition, this book provides the only available reference to Input/Output ports, undocumented CPU instructions, fixed memory areas, and much more. You will find each major subsystem of the PC explained in detail, followed by extensive reference sections that show and explain both documented and undocumented BIOS functions. These are explained in far greater detail than ever before, and cover all the major system architectures including the PC, XT, AT, EISA, and MCA. A value-added disk includes: * diagnostic and analytical tools such as IO_SPY, a TSR that monitors the current I/O port status on screen * equipment detection routines for the disk, diskette, video, and other important aspects * CPU detection routines identify the exact CPU, FPU, speed, vendor, and other critical processor information * utilities to identify and test undocumented CPU instructions * demonstration utilities to access CMOS memory, the keyboard controller, and other subsystems. 0201622777B04062001