README 1.4 KB

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  1. # $Source$
  2. # $State$
  3. # $Revision$
  4. The pc86 platform
  5. =================
  6. pc86 is an i86-based BSP that produces bootable floppy disk images that can
  7. be run on most PCs. It is intended to be quick and dirty rather than actually
  8. useful, although it may come in handy for hardware test purposes, boot
  9. loaders, and the like.
  10. The code runs in TINY mode, where CS, DS and SS all share the same segment.
  11. This means that there's not very much memory available. It would be very easy
  12. to change it to run in SMALL mode, where CS occupies one segment and DS and SS
  13. another, which would give 64kB for nearly all programs; I just haven't done it.
  14. This port uses a syscall interface, which means you get *all* of the ACK's
  15. builtin libc with no shortcuts. File descriptors 0, 1 and 2 represent the
  16. console. All reads block. There's enough TTY emulation to allow \n conversion
  17. (set RAW to turn off) and local echo (unset ECHO to turn off); this is needed
  18. to make Basic work.
  19. Language support
  20. ================
  21. Tested with C (both), Basic, Pascal, Occam, Modula-2.
  22. Basic works, but because Basic programs require access to a data file to work,
  23. and pc86 doesn't (of course) have a file system, programs won't start unless
  24. you hack the compiler not to try and open it.
  25. Example command line
  26. ====================
  27. ack -mpc86 -O -ansi -o pc86.img test.c
  28. The file pc86.img can then be copied onto a floppy and booted, or run via qemu
  29. or somesuch emulator.
  30. David Given
  31. dg@cowlark.com