CON - Graphical Console Server Reference Manual
Con is graphical console server for DROPS. The hardware is hidden behind a ``virtual'' framebuffer abstraction and accesses from multiple clients are synchronized. We denote the implemented protocol as pSLIM (``pseudo'' [S]tateless [L]ow level [I]nterface [M]achine as proposed by SUN at SOSP 1999).
Con clients may receive input events (currently only from keyboard and mouse) by implementing the stream
server interface. There are stubs available for L4Linux and XFree86 4.1.0.
Con offers limited hardware acceleration for the following graphics cards:
- ATI Mach64 (also backend scaler)
- Matrox G100, G200, G400, G450 (also backend scaler)
- S3 Savage/IX{-MX} (also backend scaler)
- VMware
- NVIDIA
The console server supports also fast YUV-to-RGB conversion using MMX functions of newer x86 processors. Supported graphics cards with backend scaler (see previous list) do the YUV-to-RGB conversion in hardware.
For most purposes, starting
con without any arguments should be sufficient. Possible command line arguments are:
-a | --noaccel
- Disable autodetection of accelerated graphics cards and use none-accelerated mode. Try this if you encounter problems with not/wrong detected graphics cards.
-i | --l4io
- Use l4io to scan the PCI bus and to map I/O memory. Use this option if you also load the l4io server.
-l | --nolog
- Don't use the logserver as output but use the kernel debugger interface for direct log output. This is useful if the log server is logs to a virtual console itself.
-o | --omega0
- Allocate interrupts using Omega0 server.
-p | --pan
- Try to pan the graphics memory so that the status line begins at 4MB page granularity. This prevents an application from overwriting the statusline if it has mapped the graphics memory.
Con expects the Common L4 Environment (L4env). The following servers are expected at runtime:
rmgr
(resource manager)names
(name server)log
(log server)dm_phys
(dataspace manager)
A GRUB menu file resides in con/doc (menu.lst) and you should read con/doc/README.
As mentioned before,
con supports an interface we denoted as pSLIM. See
There is a client library available allowing text output using pSLIM:
Additional information can be found at
http://os.inf.tu-dresden.de/~ch12/con/con.xml (in German, outdated).
- Author:
- Christian Helmuth, Frank Mehnert