[comp.sys.ibm.pc] Wanted: Help on writing a bitblter for Wyse-700 monitor.

whw@doc.ic.ac.uk (Victor Wu) (04/15/87)

Hello folks,

	I've recently bought a Wyse-700 monitor for my AT-clone and trying to
port the bitblter for the X windowing system (from Brown University) to run on
it. However, I found it is very difficult to work with this particular
monitor. The reason being that when it is at its highest resolution (ie. 1280
X 800 pixels black and white), the frame buffer is divided into two banks of
memory. One for the even scanlines and the other for the odd scanlines. Both
of them occupy the same address space A0000H to AFFFFH. To be able to read
from or write to either one banks of memory, one have to write to a control
port at address 3DF. This makes the bitblt routines very clumsy and tedious
and very inefficent. I wonder is anyone out there have any experience with
this monitor or any solution to the problem.

	Thank you very much indeed in advance for your kind attention and
help.

Victor WU
Department of Computing,
Imperial College of Science & Technology,
180, Queen's Gate,
London SW7 2BZ,
England.