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INI File | 1994-08-24 | 32.9 KB | 971 lines |
- [Main menu]
-
- The AMIDiag 4.5 main menu has the following items:
-
- {System Board menu},
- {Memory menu},
- {Hard disk menu},
- {Floppy menu},
- {Keyboard menu},
- {Video menu},
- {Misc menu},
- {User menu},
- {Options menu}.
-
- Use the left and right arrow keys to select a menu.
- Then use the up and down arrow keys to select a test.
- Press <Enter> to run the test. Press <F1> at any time to
- display a Help screen.
-
- If using a mouse, you can double-click on a menu item to select
- that item. To select a test to be run in batch mode, single-click
- on the test. Single-click on a selected test to deselect it.
-
- See also - {About AMIDiag}
-
- [About AMIDiag]
-
- AMIDiag 4.5 provides the most comprehensive tests for advanced
- PC technologies like {EISA}, {PCI}, {Plug&Play}, and {PCMCIA}.
-
- Equally outstanding is the SYSINFO utility that is part of AMIDiag.
- SYSINFO can detect resource allocation (such as IRQ and DMA
- assignments) for SCSI controllers, IDE controllers, sound cards,
- CD-ROM drives, and many other types of devices.
-
-
- [System board menu]
-
- This set of diagnostic tests checks motherboard functions.
- The tests are:
-
-
- {Basic Functionality test},
- {CPU Protected Mode test},
- {Processor speed test},
- {Coprocessor test},
- {DMA controller test},
- {Interrupt controller test},
- {Timer test},
- {Real time clock test},
- {CMOS validity test},
- {EISA system test},
- {PCI system test}
-
- See also - {Main menu}
- {About AMIDiag}
-
-
- [Memory menu]
-
- This set of tests checks the memory functions. The tests are:
-
-
- {BIOS ROM test},
- {Parity test},
- {Pattern test},
- {Walking 1's test},
- {Walking 0's test},
- {Random read/write test},
- {Address test},
- {Refresh test},
- {Cache memory test}
-
- See also - {Main menu}
- {About AMIDiag}
-
-
- [Hard disk menu]
-
- This set of tests checks the hard disk drive functions.
- The tests are:
-
-
- {Hard disk format},
- {Auto interleave},
- {Media analysis},
- {Performance test},
- {Seek test},
- {Read/verify test},
- {Check test cyl},
- {Force bad tracks}
-
- See also - {Main menu}
- {About AMIDiag}
-
- [Basic Functionality Test]
-
- The Basic Functionality Test runs in one of two modes,
- depending on the {CPU} installed in the system.
-
- If the processor is an 80286, the test is run in 16-bit
- mode and checks:
-
- * the functionality of the 16-bit registers,
- * {16 bit flags}, and
- * special 80286 instructions.
-
-
- If the processor is an 80386 or higher:
-
- The test is run in 32-bit mode and checks:
-
- * the functionality of the 32-bit registers,
- * {32 bit flags}, and
- * special 80386 and 80486 instructions.
-
- [CPU Protected Mode Test]
-
- The CPU Protected Mode Test tests the {protected mode}
- features of Intel 80286 and above {CPU}s.
-
- The processor is switched to protected mode and then all
- protected mode special instructions are tested.
-
- For example, a protected mode selector is loaded with a
- segment limit of 256 bytes. Then an LSL (Load Segment Limit)
- instruction is used to make sure it returns the segment
- limit properly.
-
- [Processor Speed Test]
-
- This test determines and displays the CPU clock speed by
- measuring the time taken to execute a specific instruction.
- The time is calculated by using a separate clock source
- with a known frequency.
-
- Special care has been taken to eliminate the effect of any
- {prefetch queue} and cache memory. The CPU speed is displayed
- in bar chart form. The CPU clock speeds of commercially
- available CPUs are displayed on the scale for reference.
-
- [Coprocessor Test]
-
- This test checks the functionality of the 80287 or 80387
- math coprocessor.
-
- The tests include loading and storing the control and
- status word, data transfer between CPU and NPX, and
- exception checking while the data transfer is in progress.
-
- [DMA Controller Test]
-
- The {DMA} Controller Test is a series of read/write tests
- on the memory address registers and page registers of DMA
- controllers 1 and 2.
-
- [Interrupt Controller Test]
-
- This test performs a series of read/write tests on the {interrupt}
- mask registers of the interrupt controller. It also checks for
- stray interrupts by setting the mask for all interrupts and
- then enabling the processor interrupt.
-
-
- [Timer Test]
-
- This test checks the accuracy of the timer count by
- calibrating it against the periodic interrupt of the real
- time clock ({RTC}).
-
- [Real Time Clock Test]
-
-
- This test checks the accuracy of the real time clock by
- calibrating it against the timer (IRQ 0) interrupt.
-
- [CMOS Validity Test]
-
- This test checks the condition of AT {CMOS} RAM
- (non-volatile memory).
-
- The test makes sure that the CMOS battery is in good
- condition and that the CMOS RAM checksum is correct.
-
- [EISA system test]
-
- This test runs on {EISA} systems only.
-
- This test performs read/write/compare tests on some
- EISA-specific {DMA} and {interrupt} controller registers.
- It also checks the EISA software NMI and fail-safe timer.
-
-
- [PCI system test]
-
- This test runs on {PCI} systems only.
-
- This test scans the PCI bus and finds all PCI devices.
- Then it uses a different procedure to find the same devices.
- It checks for all valid combinations of PCI bus number, device
- number and function number. It also checks the validity of PCI
- BIOS32 service directories and the generation of PCI special
- cycles.
-
- [BIOS ROM Test]
-
- The {BIOS ROM} test checks the data path of the BIOS
- ROM and also assures that the ROM is write-protected.
-
- A shadowed ROM may remain write-enabled by mistake, which may
- cause serious problems.
-
-
- [Parity Test]
-
- This test reads all memory locations and checks for parity
- errors in the entire memory space.
-
- All IBM AT-compatible systems include memory {parity} checking
- circuitry. When the {CPU} accesses a memory location that has
- a parity error, a bit is set in a specific register and an
- NMI (nonmaskable interrupt) is generated. The AMIDiag parity
- test captures the interrupt so that the system does not crash
- even when a parity error is encountered, Then it reads the
- entire memory region for parity errors.
-
-
- [Pattern Test]
-
- This test performs a comprehensive read/write test on the
- entire memory space, using worst-case bit patterns
- such as AA55 (1010101001010101).
-
- This test will identify most memory problems.
-
- [Walking 1's Test]
-
- This test identifies shorts on data lines. The following
- diagram explains how this test works.
-
- ┌───────────────────────────────────────────┐
- │ M E M O R Y D A T A │
- └──┐ ┌─┐ ┌─┐ ┌─┐ ┌─┐ ┌─┐ ┌─┐ ┌─┐ ┌──┘
- │D7│ │D6│ │D5│ │D4│ │D3│ │D2│ │D1│ │D0│
- └┐┌┴─┴┐┌┘ └┐┌┘ └┐┌┘ └┐┌┘ └┐┌┘ └┐┌┘ └┐┌┘
- BUS ───────┼┼───┼┼───┼┼───┼┼───┼┼───┼┼───┼┼───┼┼────────────
- └┘ └┘ └┘ └┘ └┘ └┘ └┘ └┘
-
- This test writes a rolling 1s pattern in memory. It first
- writes 1, then 2, then 4, then 8, then 16, etc, so that in the
- written data, only one bit is on at a time.
-
- Consider the memory chip shown above. It has a short between
- data bits 7 and 6 (shown as D7 and D6). The walking 1s
- test will pass up to the data pattern 20h (bit 5 on). When this
- test writes 40h (bit 6 on), it reads back 0C0h (bits 7 and 6 on),
- because bits 7 and 6 are shorted together.
-
- The walking 1s test is useful in isolating data shorts.
-
-
- [Walking 0's Test]
-
- This test identifies open data lines. The following
- diagram explains how this test works.
-
- ┌───────────────────────────────────────────┐
- │ M E M O R Y D A T A │
- └──┐ ┌─┐ ┌─┐ ┌─┐ ┌─┐ ┌─┐ ┌─┐ ┌─┐ ┌──┘
- │D7│ │D6│ │D5│ │D4│ │D3│ │D2│ │D1│ │D0│
- └┐┌┴─┴┐┌┘ └┐┌┘ └┐┌┘ └┐┌┘ └┐┌┘ └┐┌┘ └┐┌┘
- ││ └┘ ││ ││ ││ ││ ││ ││
- BUS ───────┼┼────────┼┼───┼┼───┼┼───┼┼───┼┼───┼┼────────────
- └┘ └┘ └┘ └┘ └┘ └┘ └┘
-
- This test writes a rolling 0s pattern in memory. It first
- writes FEh, then FDh, then FBh, etc, so that in the written
- data, only one bit is 0 at a time.
-
- Consider the memory chip shown above. It has an open data pin
- in bit position 6 (shown as D6). The walking 0s test will pass
- up to the data pattern DFh (bit 5 off). When this test writes
- BFh (bit 6 off), it reads back FFh, because bit 6 is open and
- will always appear as set.
-
- The walking 0s test is useful in isolating data opens.
-
-
- [Random read/write test]
-
- This test uses a pseudo-random number generator to
- generate random addresses to the entire memory area. It
- then writes random data to the location, reads
- it back, and compares the data read with the data written.
-
- Most motherboards have 32 KB 50 to 2 MB of cache memory.
- However, depending on the cache algorithm, soft or flaky errors
- in dynamic memory are sometimes difficult to catch. If a
- memory test progresses sequentially, after some time it starts
- accessing only cache memory. The random read/write test defeats
- the cache strategy and accesses the DRAM as much as possible.
-
- This test is also useful in finding cache loading problems
- in motherboards. Since this test produces cache misses more
- frequently than any other application program, this test
- exercises the cache loading thoroughly.
-
- [Address Test]
-
- This test checks for shorts and opens on address lines.
- The following diagram explains how the address test works.
-
- ┌───────────────────────────────────────────┐
- │ M E M O R Y A D D R E S S │
- └──┐ ┌─┐ ┌─┐ ┌─┐ ┌─┐ ┌─┐ ┌─┐ ┌─┐ ┌──┘
- │A7│ │A6│ │A5│ │A4│ │A3│ │A2│ │A1│ │A0│
- └┐┌┴─┴┐┌┘ └┐┌┘ └┐┌┘ └┐┌┘ └┐┌┘ └┐┌┘ └┐┌┘
- BUS ───────┼┼───┼┼───┼┼───┼┼───┼┼───┼┼───┼┼───┼┼────────────
- └┘ └┘ └┘ └┘ └┘ └┘ └┘ └┘
-
- The address test writes a value in one location of memory
- and then scans the entire memory region to find a
- reflection of that value. The address locations are so
- selected that in the complete address, only one bit
- remains set at a time. For example,, this test writes to
- memory locations 1, 2, 4, 8, 16, etc.
-
- In the memory chip shown above, address bits 7 and 6 are shorted
- together. Any value written to xxxxxx40 will also appear at
- xxxxxC0. On the other hand, if bit 7 if open, the address
- xxxxxx01 becomes the same as xxxxxx81, since address bit 7
- always remains high. The value written at xxxxxx01 will be
- duplicated at xxxxxx81.
-
- [Refresh Test]
-
- This test makes sure the refresh circuitry is functioning and
- measures the refresh interval.
-
- Bit 4 of I/O port 0061h is set every time refresh takes
- place. By polling port 0061h over a known period of time, it is
- possible to calculate the refresh interval. An error is reported
- if this interval is not within +/- 5 percent of the standard
- refresh interval of 15 microseconds.
-
- [Cache Memory Test]
-
- If AMIDiag detects {cache} memory, this test displays the
- internal and external cache memory size.
-
- [Hard Disk Format]
-
-
- THIS TEST IS DESTRUCTIVE. IT ERASES ALL DATA ON THE DISK.
-
- Use the Hard Disk Format Test to integrate a new hard
- disk into the system or reformat a used hard disk that
- has developed some bad tracks because of aging or poor
- handling. DO NOT RUN THIS TEST ON SCSI OR IDE DRIVES.
-
- [Auto Interleave]
-
- Run Auto Interleave to optimize hard disk performance.
-
- AMIDiag calculates the optimum interleave value by measuring
- the data transfer rate for several interleave factors.
-
- The hard disk is formatted with the interleave factor that
- has the fastest data transfer rate.
-
- DO NOT RUN THIS TEST ON SCSI OR IDE DRIVES.
-
- [Media Analysis]
-
- The Media Analysis routine runs a series of tests to
- locate bad tracks.
-
- DO NOT RUN THIS TEST ON SCSI OR IDE DRIVES.
-
- [Performance Test]
-
- The Performance Test determines the Data Transfer Rate,
- the Sequential Seek Time, and the Random Seek Time.
-
- The Data Transfer Rate is measured in kilobytes per second.
- The Seek times are measured in milliseconds.
-
-
- [Seek Test]
-
- The Seek Test determines the head movement capability of
- the hard disk by seeking to a specified cylinder and
- head range.
-
- A series of sequential seeks is performed, followed
- by a series of random seeks.
-
- [Read/Verify Test]
-
- This test performs sequential and random read and verify
- operations on the specified cylinder and head range.
-
- [Check Test Cylinder]
-
- The last cylinder on the hard disk is the test cylinder.
- This test performs write and verify tests on all
- sectors in the test cylinder.
-
- If all sectors on the test cylinder are bad, BIOS POST
- issues a "C (or D): Drive failure" message at system boot.
-
- [Force Bad Tracks]
-
- This routine allows you to mark a set of tracks as faulty.
-
- If you did not enter the bad tracks before performing
- a low level format, use this option to enter bad tracks at
- any time.
-
- [Diskette Format Test]
-
- This test determines the ability of the floppy disk
- controller to perform low-level formatting.
-
- It also determines the condition of the magnetic
- media inside the diskette.
-
-
- [Drive Speed Test]
-
- This test determines the rotational speed of the floppy
- drive.
-
- The ideal rotational speed, expressed in RPM
- (revolutions per minute), is:
-
- * 360 RPM for high density (1.2 MB or 1.44 MB)
- drives, and
- * 300 RPM for low density (360 KB or 720 KB) drives.
-
- [Random Read/Write Test]
-
- This test checks the random seek, read, and write
- capability of the floppy drive.
-
- The diskette used in this test must be formatted.
-
- [Sequential Read/Write Test]
-
- This test checks the sequential seek, read, and write
- capability of the floppy drive.
-
- The diskette used in this test must be formatted.
-
- [Disk Change Line Test]
-
- This test verifies the disk change line capability
- of the floppy drive.
-
- The disk change line is only found in high density
- (1.44 MB or 1.2 MB) drives. It allows the operating
- system to recognize that a diskette was
- removed from the drive and a new diskette inserted.
-
- [Controller Test]
-
- The Controller Test issues a Self Test command to the
- keyboard controller and checks for an OK response.
-
-
- [Scan/ASCII Code Test]
-
- The Scan/ASCII Code Test determines whether the pressed
- key matches its respective Scan and ASCII codes.
-
- [Keyboard Clock Line Test]
-
- The Keyboard Clock Line Test verifies that the keyboard
- clock line is working properly. This test makes sure
- the keyboard clock line is not stuck on high or low).
-
- [Keyboard Data Line Test]
-
- The Keyboard Data Line Test verifies that the keyboard
- data line is working properly. This test makes sure that the
- keyboard data line is not stuck on high or low.
-
- [Adapter Test]
-
- This option tests the video display memory at B800h or B000h,
- depending on whether the display adapter is color or monochrome.
- Since random characters are written in the display memory and
- then read back, the screen may show some irregular characters
- and colors while the test is being executed.
-
- This test can be run with both monochrome and color display
- adapters.
-
-
- [Attribute Test]
-
- This option tests the display attributes. It displays a
- screen with a blinking line, reverse video line, high
- intensity line and lines in eight colors. The screen is
- displayed in video mode 03h (video mode 07h is used
- for monochrome).
-
- This test can be run with both monochrome and color display
- adapters.
-
-
- [80x25 Display Test]
-
- This routine tests the 80x25 character set of the display
- adapter, displaying the entire character set in black and
- white, then in reverse video. The program uses video mode
- 3 (7 for monochrome).
-
- This test can be run with monochrome and color display
- adapters.
-
- [40x25 Display Test]
-
-
- This option tests the 40x25 character set of the display
- adapter, displaying the entire character set in black
- and white, then in reverse video. The program uses video
- mode 1 for this test.
-
- This test can be run with both monochrome and color display
- adapters.
-
-
- [320x200 Graphics Test]
-
- This test displays a black and white 9 x 13 window and then
- redisplays it in reverse video. Then it displays a three
- color screen, a screen filled with random dots of random
- colors, then a blank screen, and finally 256 colors.
-
- This test uses video modes 04h and 13h.
-
- [640x200 Graphics Test]
-
- This screen displays three black and white boxes, then displays
- a blank screen, then an all white screen filled with dots.
- The blank screen is then redisplayed.
-
- This test can be run only with color display adapters.
-
-
- [Page Selection Test]
-
- Color display adapters usually have several pages on
- which text can be displayed. BIOS interrupt INT 10h function
- 05h accesses different video pages.
-
- This test writes all 0s on page 0, all 1s on page 1,
- all 2s on page 2, and so on. Then it displays all video pages
- to make sure each video page functions properly.
-
- This test can be run only with color display adapters.
-
- [Color Test]
-
- This test displays all possible color combinations in
- the foreground, background, and border.
-
- This test can be run only with color display adapters.
-
- [640x350 Graphics Test]
-
- This test displays a 16-color screen, then fills the
- screen with random colors, then again displays a blank
- screen.
-
- This test uses EGA video mode 0Fh if an EGA monochrome
- monitor is detected. It uses EGA mode 10h if an EGA color
- monitor is detected.
-
- This test can only be run with EGA or higher video
- adapter.
-
-
- [640x480 Graphics Test]
-
- This test displays a 16-color screen, then fills the
- screen with random colors, then displays a blank screen.
-
- This test uses VGA mode 11h if a VGA monochrome monitor
- is detected. It uses VGA mode 12h if a VGA color monitor is
- detected.
-
- This test can only be run with VGA or higher video
- adapters.
-
-
- [Serial Port Test]
-
- This test checks the serial ports found in the global
- memory locations 40:0 to 40:7. A maximum of four serial
- ports (COM1 through COM4) are tested. The communication
- parameters, such as the number of data bits, number of stop
- bits, parity type, etc.) can be individually selected
- for each serial port. All parameters can be entered in a
- single edit window.
-
- The serial port tests are:
-
- 1 Register test,
- 2 Interrupt ID test,
- 3 Internal loopback test,
- 4 Line status test,
- 5 Modem control register test,
- 6 Data transfer test (baud rates - 300 bps to 9600 bps),
- 7 External loopback test.
-
- [Parallel port test]
-
- This test checks the parallel ports found in the global
- memory locations 40:8 to 40:d. A maximum of three
- parallel ports (LPT1 through LPT3) are tested. The
- test parameter window asks if a printer or external loopback
- plug is connected. If none is connected, only the register
- read/write test on the parallel port data buffer is
- performed. Otherwise, the following tests are performed:
-
- 1 Register test,
- 2 IRQ activation test,
- 3 Pattern printing,
- 4 Bold letter printing,
- 5 Compressed mode printing,
- 6 Printer form feed test.
-
- If a printer is connected, check the printer output.
- If an external loopback is connected, there is no printed
- output, but the response from the parallel port controller
- is checked.
-
- [Set/view run time parameters <F2>]
-
- Selecting this option is the same as pressing <F2>
- from the main menu.
-
- This option allows you to specify different groups
- of parameters:
-
- * Hard disk test parameters
- * Hard disk types
- * Floppy test parameters
- * Batch mode parameters
-
- You can specify the physical dimensions of the hard disk as
- well as the starting and ending cylinder numbers and head
- numbers where the tests will be executed.
-
- [Load/save run time parameters <F7>]
-
- Selecting this option is the same as pressing <F7>
- from the main menu.
-
- This option allows you to save certain run time parameters
- in an ASCII file with a .SAV file extension, or to load
- these parameters from a .SAV file.
-
- The parameters that are saved include information on the
- tests that have been selected for batch mode execution
- (by pressing <F3>, <F4>, or <F8>), the batch mode run time
- option (time bound, pass bound, or continuous), the error
- logging option, the error log file name and heading, and
- other test parameters.
-
- [System Information]
-
- This option allows you to run SYSINFO.EXE from
- within AMIDiag.
-
- SYSINFO.EXE displays memory block details, a software
- interrupt summary, IRQ allocation information, CMOS
- information, the contents of AUTOEXEC.BAT and
- CONFIG.SYS files, and lots of other information.
-
- SYSINFO.EXE can also be run from the DOS command line
- as a standalone program.
-
- [Configuration program]
-
- This program allows you to run CONFIG.EXE from within
- AMIDiag. CONFIG.EXE can also be executed from the DOS
- command line.
-
- CONFIG allows you to define memory organization and CPU
- components graphically, so that in case of error, the
- exact location of the component is displayed on a
- graphics screen in AMIDiag.
-
- CONFIG also allows you to integrate cache controller
- programs and user-defined diagnostic programs with AMIDiag.
-
- CONFIG displays the faulty memory chip or CPU component when
- called by AMIDiag via a special command line option.
-
- It also loads or saves configuration data to or from an ASCII
- file.
-
- [Report generation]
-
- This option allows you to specify if error messages are
- logged to a disk file, a printer, or a serial port.
-
- If you select "Yes" and the previous selection was "No",
- type the name of the log file as well as an optional
- ASCII header string for identification.
-
- If you select "Yes" and the previous selection was "Yes"
- and the log file name is the same, choose whether the new
- error log file is appended to the old file or the old file
- is rejected and a new error log file is started.
-
- Similarly, if you select "No" and the previous selection
- was "Yes", you must discard or save the old log file.
-
- [Change color settings <F10>]
-
- This selection is the same as pressing <F10> from the
- main menu. By repeatedly pressing <F10>, you can rotate
- the color scheme and see the different color sets
- available.
-
- When you select a color set, press <Enter> to save that
- color set and return to the main menu.
-
- [Virus scanning]
-
- This is a new feature in AMIDiag that will let you SCAN
- whole or part of your disk for virus. This option will
- load the AMU(Anti-viral Maintenance Utility) that provides
- a graphical user interface for virus scanning.
-
- [Toggle speaker on/off]
-
- This option allows you to enable or disable the system
- speaker.
-
- If the speaker is disabled, memory tests and others tests
- that issue beeps will run in quiet mode.
-
- The speaker can be enabled by selecting "Speaker on"
- in the dialog box displayed by this option.
-
- [DOS shell]
-
- This option allows you to return to the DOS prompt
- temporarily.
-
- You can issue all DOS commands from the DOS shell.
- Typing "Exit" from the DOS prompt returns to AMIDiag.
-
- [Exit AMIDIAG]
-
- Select this option to Exit AMIDiag. You will have the option
- of either returning to DOS or system reset.
-
- [CPU]
-
- CPU is acronym for Central Processing Unit. It is the
- brain of the computer, where building blocks for arithmetic
- and logical operations and control circuitry is located.
-
- In IBM PC market, the Intel 80x86 CPUs are most popular.
- Other vendors who are making 80x86-compatible CPUs
- include IBM, Cyrix, AMD, Texas Instrument etc.
-
- [16 bit flags]
-
- The CPU flag is a special register which indicate the status
- of the operations done by CPU. The different elements of the
- flag register are the carry flag, the zero flag, the sign
- flag etc. For instance, when the CPU performs an ADD
- instruction, all the three flags mentioned before (carry flag,
- zero flag, etc.) is modified.
-
- The 80286 CPU flag register has 16 bits in it. The "16 bit
- flags" refer to a flag format compatible to 80286 CPU.
-
- 16 bit EFLAGS
-
- 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0
- 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
- ┌─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┐
- │ │N│I O│O│D│I│T│S│Z│ │A│ │P│ │C│
- │0│F│P L│F│F│F│F│F│0│0│F│0│F│1│F│
- │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │
- └─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┘
- 0 1 1 1 0 0 1 0 0 1 0 0 0 1 1 0
-
- NF Nested task flag (bit 14).
- IOPL Input/Output privilege level (bits 13-12).
- IF Interrupt enable flag (bit 9).
- TF Trace flag (bit 8).
- SF Sign flag (bit 7).
- ZF Zero flag (bit 6).
- AF Auxiliary Carry flag (bit 5).
- PF Parity flag (bit 2).
- CF Carry flag (bit 0).
-
- [32 bit flags]
-
- The CPU flag is a special register which indicate the status
- of the operations done by CPU. The different elements of the
- flag register are the carry flag, the zero flag, the sign
- flag etc. For instance, when the CPU performs an ADD
- instruction, all the three flags mentioned before (the carry flag,
- zero flag, etc.) is modified.
-
- 80386 and above CPUs have 32 bits in the flag register. The
- "32 bit flags" is a flag format compatible with these CPUs.
-
- 32 bit EFLAGS
-
- 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
- 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
- ┌─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┬─┐
- │ │ │ │ │ │ │ │ │ │ │I│V│V│A│V│R│ │N│I O│O│D│I│T│S│Z│ │A│ │P│ │C│
- │0│0│0│0│0│0│0│0│0│0│D│I│I│C│M│F│0│F│P L│F│F│F│F│F│0│0│F│0│F│1│F│
- │ │ │ │ │ │ │ │ │ │ │ │P│F│ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ │
- └─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┴─┘
- 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 0 0 1 0 0 1 0 0 0 1 1 0
-
- ID Identification flag (bit 21).
- VIP Virtual interrupt pending (bit 20).
- VIF Virtual interrupt flag (bit 19).
- AC Alignment check (bit 18).
- VM Virtual 8086 mode (bit 17).
- RF Resume flag (bit 16).
- NF Nested task flag (bit 14).
- IOPL Input/Output privilege level (bits 13-12).
- IF Interrupt enable flag (bit 9).
-
- [Protected mode]
-
- Intel 80286 and higher CPUs have two modes of operation: Real Mode
- and Protected Mode.
-
- In Real Mode, the {CPU} behaves essentially like an Intel 8086 CPU.
- In Real Mode, address space is limited to 1 Megabyte and only one
- task can be executed at a time. No protection is available.
- DOS runs in Real mode.
-
- Protected mode accesses up to 4 Gigabytes of memory (for 80386
- and higher CPUs), multitasking, I/O privilege levels, and
- protection. Protected Mode also has virtual 8086 mode to
- emulate multiple 8086 machines running simultaneously.
- OS/2 and Windows NT operate in protected mode only.
-
- [Prefetch queue]
-
- While the Intel 80x86 CPU is executing one instruction, it
- can fetch subsequent instruction and store them in a queue,
- to reduce overall execution time. The depth of this prefetch
- queue varies from processor to processor. Even within the same
- family, the 80386SX and DX prefetch queues are not the same size.
-
- [DMA]
-
- Direct Memory Access (DMA) is the direct transfer of data to or
- from a peripheral device such as a hard disk drive with no
- intervention from the CPU.
-
- A DMA controller, when programmed, takes care of all DMA
- transfer issues, such as DMA timing, number of bytes to transfer etc.
-
- [Interrupt]
-
- An interrupt is a signal that stops what the CPU is currently
- doing, allowing the CPU to perform a higher priority task. An
- interrupt is usually generated by a peripheral device demanding
- attention. After the interrupt is serviced, the suspended task
- is resumed at the point it was stopped.
-
- [RTC]
-
- The Real Time Clock (RTC) is found in all IBM AT-compatible
- computers. It provides a separate clock source, independent
- of the CPU clock speed, for updating the system date and time.
- This clock source can also be used as an alarm.
-
- [CMOS]
-
- Complimentary Metal Oxide Semiconductor (CMOS) is a method of
- fabricating integrated circuits (ICs). It is more frequently
- used to specify an IC that has been produced by this method.
- All CMOS ICs consume very little energy.
-
- The CMOS RAM in IBM AT-compatible systems stores vital
- system configuration data. The CMOS RAM is battery backed -
- its content remains intact even when the system is switched off.
-
- [EISA]
-
- Extended Industry Standard Architecture (EISA) is a 32-bit
- bus standard that enhances the existing 16-bit ISA bus.
-
- EISA also allows level-triggered interrupts, so the same
- interrupt can be shared by more than one device.
-
- [PCI]
-
- Peripheral Component Interconnect (PCI) is a popular local bus
- standard. A local bus allows peripherals like the display
- controller or disk controller to access the CPU bus directly,
- permitting much faster operation than the traditional ISA
- (Industry Standard Architecture) bus.
-
-
- [PCMCIA]
-
- Personal Computer Memory Card International Association (PCMCIA)
- developed and maintains a standard for credit-card-sized
- PC peripherals devices, called PC Cards.
-
- PC Cards, can include I/O controllers, memory, and mass storage
- devices. PC Cards are mostly used in AT-compatible notebook
- computers. A major advantage is the PC Card size and portability.
-
-
- [Plug&Play]
-
- Plug-and-play is a new computer industry standard that permits a
- computer to automatically configure system resources, foregoing the
- necessity for hardware switches and jumpers.
-
-
- [Cache]
-
- Caching speeds access to information in a slower device by
- storing a part of the slow devices information in a much
- faster device.
-
- For example, ISA system memory uses DRAMs (Dynamic Random
- Access Memory) with typical access times of 60 to 70 nanoseconds.
- However, if most memory accesses are to a 64 KB block of
- system DRAM memory, the data in that 64 KB of DRAM can be
- copied to cache memory.
-
- Cache memory uses SRAM (Static Random Access Memory) with
- typical access time of 12 to 14 nanoseconds.
-
- As long as the 64 KB block of data is not modified, the
- CPU can access this data from fast cache memory, permitting
- a significant boost in performance.
-
- [Parity]
-
- Parity of a block of data storage in memory is the sum of all
- bits set in the unit of memory. It is either odd or even.
- In even parity,, the number of bits set to 1 must be odd. If
- it is not, the data is in error.
-
- Computer memory is organized in bytes (collection of eight
- bits). The odd or even parity is maintained by adding a bit,
- called the parity bit. This bit is made 0 or 1 by the parity
- generation circuitry in such a way that the sum of all set
- bits including the parity bit is always kept even or odd.
-
-
- [Help on help]
-
- There is no help on help.
-