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Next: Fifth Annual EMME/2 Users' Conference Up: EMME/2 News 9 April 1990 Previous: Bugs + Fixes

DOS/DSI Corner

If you are using a PC with a 1024x768 graphic adapter, such as Toucan or IBM 8514/A, you most likely also use the PLOTDEV7.HRS display driver (see your CONFIG.SYS file, if in doubt). While this driver is perfect for the EMME/2 plots, it produces screen reports which are only barely readable. This is due to the very small font size used in this driver and the fact that the horizontal and vertical spacing between the characters is minimal. In order to make the reports on these devices more readable, we have developed a different version of the driver, named PLOTDEV9.HRS, which uses a larger font and increased vertical and horizontal character spacing. If you use a 1024x786 graphic board and are bothered by the small report characters generated by PLOTDEV7.HRS, please contact INRO in order to receive a pre-release copy of the PLOTDEV9.HRS diskette.

By the way, are you aware that the speed of the Toucan board (and most other super-VGA type boards) can be increased drastically if the Video-BIOS, which is usually located in a EPROM memory on the board itself, is relocated into the RAM memory of your computer. While the EPROM is read by the CPU by accessing the slow 8 bit bus (usually running at 8 MHz), the RAM memory can be accessed in 16-bit (80286) or 32-bit (80386) mode using the full processor speed. This might results in an increase in speed of up to a factor five. Thus, if your graphic display seems painfully slow, read on, there might be an easy cure for it!

There are two ways to relocate the slow EPROM Video-BIOS into the fast RAM: Firstly, most manufacturers provide special software driver programs which, when installed, will relocate the Video-BIOS into the base memory of the PC. For the Toucan board, this driver is called FASTBIOS.SYS and is on the diskette provided with the board. For other graphic display boards, look for files named RAMBIOS, TVGABIOS or similar. The second possibility to relocate the Video-BIOS is the Shadow-RAM feature which is available on most recent 80386 machines, as well as on some of the fast 80286 systems. This approach is provided directly by the system hardware and is independent of the graphic card used. In this case, RAM memory is also available in the address range between 640kb and 1Mb, which is where the EPROMS with the SYSTEM and VIDEO BIOS are located. If the Shadow-RAM feature is enabled (usually in the SETUP procedure), the contents of the EPROMS are copied into the RAM memories at the same location during the booting process and the EPROMS are then disabled. If both, installable software driver and Shadow-RAM, are available on an installation, the latter is preferable, since it does not occupy any of the precious 640kb base memory.


next up previous
Next: Fifth Annual EMME/2 Users' Conference Up: EMME/2 News 9 April 1990 Previous: Bugs + Fixes


Heinz Spiess, EMME/2 Support Center, Thu Jun 6 14:21:14 MET DST 1996