FreeGEM 4.0 video drivers
=========================

  This zipfile contains the following FreeGEM drivers, compatible with 
GEM/4.0 (Artline):

Driver      | Resolution | Colours | Supported hardware
============+============+=========+=========================================
SDCAT10.EGA |  640x400   |   2     | AT&T 6300, Toshiba 3100e, DEC VAXmate
SDEH110.EGA |  640x350   |   2     | EGA mono
SDEH810.EGA |  640x350   |   8     | EGA colour
SDEHF10.EGA |  640x350   |  16     | EGA colour
SDHRC10.EGA |  640x350   |   2     | Hercules
SDPSC10.VGA |  640x480   |  16     | VGA 
SDPS810.VGA |  640x480   |   8     | VGA 
SDPS410.VGA |  640x480   |   4     | VGA 
SDPSM10.VGA |  640x480   |   2     | MCGA 
SDU8610.VGA |  800x600   |  16     | Trident, Paradise, EGA Wonder, C&T
SDUNI10.VGA |  640x480   |  16     | EGA/MCGA/VGA "universal" driver
SDV1010.VGA | 1024x768   |  16     | VESA
SDV8610.VGA |  800x600   |  16     | VESA
============+============+=========+=========================================

 These drivers differ from the stock GEM/4 ones in having the following added
features:

- Codepage support. If GEM.CPI is present, the correct codepage will be 
  loaded from it.

- Support for the FreeGEM v_delay() function, allowing these drivers to be
  used in FreeGEM if desired.

Other compatibility issues
==========================

  VIDPATCH.EXE has been supplied in case the automatic video mode probes 
in SDUNI10.VGA or SDCAT10.EGA do not work as expected. The following commands
override the probe:

VIDPATCH SDUNI10.VGA 0	  -- force EGA mono
VIDPATCH SDUNI10.VGA 1	  -- force EGA colour
VIDPATCH SDUNI10.VGA 2	  -- force VGA/MCGA mono
VIDPATCH SDUNI10.VGA 3 	  -- force VGA colour
VIDPATCH SDUNI10.VGA AUTO -- go back to automatic probe

VIDPATCH SDCAT10.EGA 6	  -- force CGA mode
VIDPATCH SDCAT10.EGA 64	  -- force AT&T 6300 mode
VIDPATCH SDCAT10.EGA 116  -- force Toshiba 3100e mode
VIDPATCH SDCAT10.VGA AUTO  -- go back to automatic probe

  It is also used to configure SDU8610.VGA if this cannot detect the 800x600 
mode used by your card. As supplied, the driver probes the modes used by VESA, 
Trident and Paradise cards. If you have a different make (eg, Oak or 
Chips & Technologies) you need to set the video mode by hand:

VIDPATCH SDU8610.VGA <mode>

where <mode> is a decimal number. For example, 

VIDPATCH SDU8610.VGA 82

selects the 800x600 mode that Oak chipsets use.



