Improved version of BeebEm 0.9 for Unix/Linux

I have compiled an improved version of BeebEm 0.9 (written by Dave Gilbert). The changes aren't revolutionary, but are making the work with the UNIX version of BeebEm much more pleasant (and user friendly). Here is a list of the changes:

The BBC screen is emulated in a 640x512 window and not in a 640x256 window as in the original version. The screen isn't distorted anymore.
I have introduced following changes which Richard Gellman made to the MS Windows version of BeebEm:

Timing differences when a 6522 VIA timer reaches zero (Revs now works properly).
6845 CRTC: 3 cycle VSync delay, not a 2 cycle VSync delay (removes flicker from Revs).

The ROM images are now located in /var/lib/beebem/romimg
No changes to the source code and no recompilation are needed when a new ROM image is added: Just insert a new line to the file /var/lib/beebem/romimg/romimg.rc where each ROM image is associated to a ROM bank. BeebEm looks in this file when it is started and decides which ROM image is loaded. Example of a romimg.rc file:
OS os12 ROM basic 0xf ROM dnfs 0xd
(The columns are TAB separated)
I have included a shell script which starts BeebEm from the Linux console by starting a new X server without a window manager in the correct colour depth (8 bit). Unfortunately BeebEm only works in 8 bit mode and as most people use a 24 bit or a 32 bit display it makes sense to start BeebEm on an another Linux virtual terminal with its own X server. You can switch between your regular desktop and the emulated Beeb display by pressing [CTRL][ALT][function key]. The emulated 640x512 display is placed at the center of an 800x600 X display with a black background.

It also looks better if you don't have a window border around your emulated screen as most games don't use the full width or height of the screen, so that the distance between the window border and the games display isn't constant. Since you don't have a window manager running, you don't have to bother about pressing some key combinations.

Installing instructions

Simply download the precompiled package beebem0.9p1.tgz and log in as root. Slackware users should execute the command installpkg beebem0.9p1.tgz. Users of other distributions should execute the following commands: (sorry, I did not made a RPM or DEB package yet)

cd / tar zxvf beebem0.9p1.tgz

Then make sure that 800x600 is the default resolution for 8 bit displays (It doesn't hurt if your resolution is better, but it is nicer to have a lower resolution). You have to change your /etc/X11/XF86Config file or use a tool like xf86config. Then you can invoke the script beeb from the Linux console (not from an X terminal):

beeb diskimage.ssd

diskimage.ssd is automatically used as the default disc image. You can quit BeebEm by pressing [CTRL][ALT][BACKSPACE]. Your X cursor should be over the BeebEm area as otherwise BeebEm would not receive any key events.

Postscript

A nice idea would be to create a 640x512 Modeline for XFree86. Then you would be running a real full screen Beeb emulator. To do this you should also replace the numbers 80 and 44 by 0 in the file beebwin.cc line 76 and recompile BeebEm (beebem0.9p1.src.tgz). I do have a LCD display, so I can't test this.

Files

beebem0.9p1.tgz: Precompiled package (ROM images included)
beebem0.9p1.src.tgz: Source code (without ROM images or shell scripts)

Improved version of BeebEm 0.9 for Unix/Linux

Installing instructions

Postscript

Files

Links