
                                f6x86
                                =====

What is f6x86?
==============

f6x86 is an xforms based program for viewing/setting some of the
Cyrix/IBM 6x86 CPU configuration registers.
It uses the program 'set6x86' by Koen gadeyne (koen.gadeyne@barco.com)
for the actual manipulation of the registers. set6x86 is included with
the f6x86 package.

The registers accessible with f6x86 are:-

Read/Write:   MAPEN SUSP_HLT LINBRST WT_ALLOC NC1 DTE_EN

Read only:    IORT DIR0 DIR1 ARR[0-7] RCR[0-7]

My restrictions on the read-only nature of some of the registers (except
DIRx). You may, of course, change any of the registers (except DIRx) with
set6x86 from the command line.

For more information, read the file ./set6x86/README and get Cyrix's
data book:- 
             ftp.cyrix.com:/6x86/

             6X-ABDB.PDF   ( 361748 bytes) - abbreviated data book
             6X-DBOOK.PDF  (2039298 bytes) - full data book

Please take care when using f6x86. It is possible to crash your
computer if you set unsupported/silly things. However, if you only
'quit without saving' it seems quite safe. (FLW)

Installing.
==========

To install f6x86 you must have (at least) version 0.81 of the xforms
library ( http://bragg.phys.uwm.edu/xforms ) installed on your system.

    make     will make the binaries (f6x86 and set6x86).

    make install   (as root) installs the binaries and sets the suid
                   bit of set6x86. The default path is /usr/local/bin
                   Edit the Makefile if you want it somewhere else.


Using f6x86.
===========

It should be pretty obvious. :)

My motherboard's default is to leave the 'map enable' register OFF
after booting. This means that some of the registers are unavailable.
Buttons that are gold in colour and entries that are marked 'unknown'
mean that that register is not accessable.
To enable these registers, click on the 'all registers enabled' button.
The gold buttons should turn red or green, and the unknowns should
become know. If you 'quit without saving', the map enable register
will revert to the value it was when you started.


WARNING to SYSADMINS.
====================

Once installed, f6x86 is executable by any user who has an xterm.
Setting some of the CPU registers to unsupported or silly values
can cause the computer to hang/crash. f6x86 does not access most
of the 'dangerous' registers, but as set6x86 is available and suid
root, a user can alter *any* register if they have the information.

Unless you trust all your users, I would reccomend removing the
suid bit from /usr/local/bin/set6x86, and only use it as root.


Copying.
=======
                  f6x86 is:
                  ^^^^^
 Copyright (C) 1996  Ian J Peters.  (ijp@floot.demon.co.uk)

  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

                   set6x86 is:
                   ^^^^^^^
 Copyright (C) 1996  Koen Gadeyne.  (koen.gadeyne@barco.com)

  GNU GPL also.

     See the file COPYING for more information about the GPL.

   ===================   end of README  ======================
