path: root/c/README.DOS
blob: 5219479910238532dd36e559e63dddff675acc3f (plain) (tree)







#   $Id$

The RTEMS build procedure was designed with the capabilitiies of a 
typical UNIX computer in mind.  Making this procedure work under MS-DOS
is not that difficult but requires that MS-DOS versions of a number
of UNIX utilities be acquired and installed.  For time being, the 
best advice which can be offered is:

    "This is a nasty question, since when I first set up the DOS machine
     (long before I acquired RTEMS) I ftp'd a bunch of different tool
     sets (all from SimTel), and then picked individual tools from each 
     set that worked best for me.  The djgpp tools are probably a good 
     starting point, especially to get a working sed.  Next the gnu tools 
     in SimTel/msdos/gnuish, and then others.  Sorry I can't give you more
     specific names.  The only real requirement for the tools is that
     they *must* accept redirection of command line arguments from a file
     using the '@' notation (i.e., "mkdir @/tmp/args" reads the argument
     list from file /tmp/args)."

There is a special version (source and executable) of GNU make 3.71 for
MS-DOS which minimizes the amount of memory used by recursive makes
available on in the file: 


Many of the RTEMS specific utilities used in the build and installation 
are UNIX shell scripts.  On a UNIX host, these are normally interpreted
by the Bourne Again Shell (BASH) or the Korn Shell (ksh).  Most of these
scripts can be successfully executed with the following shell from the
MS-DOS archives from Simtel. 


Please be sure to use the 16-bit version.  The Simtel archives are 
available from as well as a number of mirror sites.

go32 dumps the stack when a program seg-faults, and if this happens while
on an alternate stack an infinite loop can ensue.  Setting the environment
variable GO32="core /tmp/core" will prevent more than 20 lines or
so of stack information from being dumped after a crash, and the output
will go to a file rather than the screen.

The go32 debuggers get confused by the relocated stacks used by tasks,
and tend to crash when variables are inspected.

djgcc include files
In general, we use RTEMS include files because these contain the proper
declarations for the libc, and in particular, the stdio functions.
When calling go32-specific functions it is necessary to include some 
djgpp include files, as well.  Unfortunately, there are some disagreements
between RTEMS and djgpp as to how certain functions and types are 
declared.  In these cases, the RTEMS source have been modified to 
special-case the differences.

* Pressing F12 will immediately abort the program.
See lib/libbsp/i386/go32/console/inch.c.

* lib/libbsp/i386/go32/timer uses the on-board timer chip by default, 
which has a resolution of about 1 microsecond.  However, if executing 
on a Pentium processor you can use the on-chip 64-bit cycle counter, 
which counts at whatever clock rate your processor runs at.  To enable 
this, set RTEMS_CPU_MODEL=pentium in make/custom/go32.cfg.