$Id: KnownBugs,v 1.2 1996/10/10 22:31:22 james Exp $

Known Bugs
==========

There are probably plenty of bugs I don't know about, though I think
that the CPU emulation is good as long as you stick to legal, documented
opcodes. Here's a few problems I know about...

o The mark/space ratio for flashing teletext is a guess. I haven't a
  clue what it really is.

o The emulator possibly only works on pseudo-colour X displays. I
  haven't tried it on any others.

o The MODE 7 screen emulation flickers because it updates the whole
  screen when it changes, rather than just the changed bits, but I
  haven't worked out a suitable way to optimise that yet. The reason it
  works this way is because of the handling of double height characters
  -- the context of each line may change because of a change in the line
  above it.

o The code for re-initialising the screen when a snapshot has been
  loaded is quite horrid and is probably the source of a number of bugs.
  It needs more thought and work.

o There are numerous places where I don't know how the emulator should
  handle a given situation. These are usually documented in the code,
  but will cause a fatal error if encountered.

o The cursor isn't implemented for bitmapped modes.

o Handling of mixed case in filenames is incomplete. If a filename is
  mixed case on the disk, it's exact name must be used in any command
  for loading or running it.

o Not exactly a bug -- more of a feature, really. Although you won't
  hear anything, the emulator still does all that's necessary from the
  programming point of view to make sounds even if you don't have sound
  support. This means that there will be delays in programs that play
  sounds before they continue. The emulator hasn't crashed, honest :-)

o Handling of hardware-scrolled screens isn't perfect.  In the efs-demo
  and xdfs-demo directories there's a program called B.DEMO that will
  usually demonstrate the problem.

o Changing the Horizontal Sync. register in the CRTC isn't implemented
  but is required for some games.

o The counter in Hopper is screwy.  I did have this working at once
  stage, but I've broken it again.

o The screen window overlaps the window with the LED status in sometimes.


There must be other bugs, too, because otherwise all the software I have
would work properly, wouldn't it ?


Revision History
================

$Log: KnownBugs,v $
Revision 1.2  1996/10/10 22:31:22  james
Updates for v0.3.

Revision 1.1  1996/09/21 19:14:32  james
Added new documenation files : doc/Configuration doc/DataXfer
doc/DiskEmulation doc/Keyboard doc/KnownBugs doc/MailingLists doc/Options
doc/RomPatches doc/WorkingSoftware

