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22AUG03 - HVVCBIOS.TXT - Using the HVFont in a Video Card's ROM BIOS
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The HVVCBIOS.ZIP archive contains files - and information - that may allow
you to replace the full screen VGA OEM "hardware" fonts in your computer's
video card with ProCon's Hi-Visibility HVFont.

Doing so will allow the clearer HVFont font to be used in full screen MS-DOS
applications running under:-
  MS-DOS mode, and
  All Windows true "DOS Boxes".

It will NOT change the font used in:-
  Windows DOS or NT terminal "Boxes" run in a "Windowed" Window, or
  Windows NT/2000/XP 32 bit full screen Console modes.

(Our HVDOSBox.FON is designed to be used in "Windowed" Windows, and our
HVCPIFNT package allows you to change the fonts used in Windows NT/2000/XP
full screen Console modes.)


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What is a VGA OEM Hardware Font?
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The so called "hardware" OEM fonts are provided as part of the ROM BIOS in
the computer's video card.

BIOS fonts generally use the U.S. English PC8 character set - Codepage 437 -
although some cards sold in Europe provide a Codepage 850 implementation.

The full screen fonts are stored as bitmaps in the BIOS data area and are
copied into the computer's memory during the boot process. Several font
sizes are provided. The most important is 8x16 (8 pixels wide, 16 pixels
high), but 8x8 and 8x14 fonts are also common.

All video cards should provide 8x16 and 8x8 fonts. Some cards may not
include an 8x14 font, as the VESA standard now encourages manufacturers to
drop this font to make room for other video ROM functions.

The actual sizes are a byproduct of the history of video card resolutions.
In modern PCs, they allow the standard VGA 640x480 pixel resolution to
support an 80 character wide display with a user specified number of text
lines (usually 25, 28, 30, 40, 43, or 50).


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How can these fonts be changed?
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Modern computer video cards hold their software and font images in EEPROM
(Electrically Erasable Programmable Read-Only Memory) so that bugs can be
corrected and new features added.

Manufacturer's websites provide updated binary ROM image files - and "flash"
utilities that use these image files - so that card purchasers can update
the BIOS in their cards.

Unfortunately very few manufacturers' utilities allow you to view - or
change - the embedded fonts within the video card's ROM.

However, for most popular video cards, there are public domain editors
available that allow you to replace the manufacturer supplied fonts and
often "tweak" some of the card parameters to optimise performance.


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To update a video card with changed fonts
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* * * * * * * * * * * * * * * * CAUTION * * * * * * * * * * * * * * * * * *

Flashing a video card's ROM BIOS involves some risks. For example:-
1. It will probably void the manufacturer's warranty.
2. It could destroy your video card.
3. It can leave your screen unreadable until the card is restored.

The risks can be minimised if you meticulously follow the instructions
provided with the manufacturer's flash utility - and take the extra
precautions recommended below. In any case YOU assume ALL RISKS INVOLVED.

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

1.  Go to the video card manufacturer's website and download the correct
    flash utility for your video card.

2.  Check the website - or search the internet - for a video ROM BIOS editor
    for that type of video card. Download it.

3.  Set up a MS-DOS boot floppy containing a copy of the flash utility.
    (Hardware flash utilities must be run from DOS - not Windows!)

4.  Boot to DOS from the floppy. Use the flash utility to save a copy of the
    current video card's ROM BIOS as a binary image file. Save a copy of
    this file on both the floppy and the harddisk.

5.  Most flash utilities allow you to verify an image file and compare it
    with the current video state. Do this for both binary image files.

6.  Create a GOBACK.BAT batchfile on the floppy that will flash the video
    ROM using the ORIGINAL binary image file. Structure it like this:-

       ECHO Press a Key to Restore Old Video ROM, or
       ECHO <Ctrl><C> to Abort . . .
       PAUSE
       SET LGFN=C:\GOBACK.LOG
       ECHO Starting Video ROM Restoration > %LGFN%
       . . . then the command to flash the video . . . >> %LGFN%
       ECHO Video ROM Restore Complete! >> %LGFN%
       TYPE %LGFN%
       COPY %LGFN% PRN

7.  Switch the printer on, and run GOBACK.BAT to flash the BIOS. Wait for
    the logfile to print and record how long the whole process takes. Some
    flash utilities can take several minutes. NEVER stop a flash utility
    before it completes! Examine the logfile printout for error messages.

8.  Remove the floppy and reboot the PC. Check thoroughly to ensure all
    video functions and modes are working.

9.  To produce a "fail safe" boot restoration process with the verified
    image file, append the following line to the floppy's AUTOEXEC.BAT file
    so that it runs GOBACK.BAT:-

       CALL GOBACK.BAT

    (Remember: If something goes wrong with a BIOS update you may not see
    anything on the screen. You must remember to press a key in response to
    the PAUSE command and then wait long enough for the restore process to
    complete - relying only on feedback from disk drive lights and the
    printer, etc.)

10. If you wish to update the BIOS using the manufacturer's latest image
    file do it now. Create a similar batchfile - GOUPDTE.BAT - and follow
    the same procedure using the new image file.

    When you boot to DOS from the floppy, hit <Ctrl><C> when prompted to
    bypass GOBACK.BAT. Run GOUPDTE.BAT and wait for the log file to print.

    After upgrading, use the PC for several days to ensure there are no
    incompatibilities with the new release.

11. Copy the original - or verified - image file and use the video ROM BIOS
    editor to replace the fonts in the renamed copy with the appropriate
    HVFont files (HV8X8.FNT, HV8X16.FNT, etc.,).

12. Create a GOHVFONT.BAT batchfile (similar to GOBACK.BAT) on the floppy to
    flash the video ROM using the MODIFIED binary image file. (Make sure you
    do NOT overwrite any files necessary to restore the original ROM.)

13. Boot to DOS from the floppy. Hit <Ctrl><C> when prompted to bypass
    GOBACK.BAT. Run GOHVFONT.BAT and wait for the log file to print.
    Remove the floppy, reboot and you may see the new fonts being used
    during the boot process.

While this may sound tedious, it provides a relatively foolproof process
that can be largely automated. (Use the included batch files as templates
for your own flash procedures).

Restoring improperly flashed "dead" video cards is more tedious!


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Files included in the HVVCBIOS.ZIP Package
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The ZIP archive file should contain the following files:-

  Documentation Files
    HVVCBIOS.TXT - This file
    See: http://www.procon.com.au/GCM-URLS.htm for a list of URLs 
    for Video Card ROM BIOS Flash Utilities and BIOS Editors/Updaters.

  DOS Template Batch Files (Edit as required)
    GOBACK.BAT   - Restore video card's original ROM image
    GOHVFONT.BAT - Flash video ROM with new image file

  VGA BIOS Utilities
    SHOWVBIN.EXE - Windows Console Utility to Display Fonts in a
                   Video Card's ROM BIOS Image File
    SHOWVBIN.TXT - Documentation for SHOWVBIN

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