Program:  k6wc.exe

Author:   Uart

Function: Enables one or two Wite Combining memory range for any of
          k6-2(cxt core), k6-3, k6-2+ or k6-3+ cpu's.

OS:       DOS, Win95/98/98SE. Should be run from autoexec.bat with no protected
          mode drivers loaded. Won't run if emm386.exe is loaded.

Usage:    "k6wc.exe  WC_Range_Base_Address_in_Hex  WC_Range_Size_in_Mbytes" or
          "k6wc.exe Hex_Address1  MB_size1  Hex_Address2  MB_size2"
        

Example1: "k6wc.exe e0000000 16"  ;(without quotes) enables Write Combining
          for a 16 Mbytes range at starting at hex address 0xE0000000.

Example2: "k6wc.exe e0000000 16 e4000000 16"  ; Enables write combining for
          one 16MB range starting at hex address 0xE0000000 and for another
          16MB range starting at hex address 0xE4000000

Example3: "k6wc.exe 0 0 0 0"   ;Disable all write combining.


Notes:  1.Get the program "setk6.exe" if you don't know what base address
          (LFB) to use. Run setk6.exe with no parameters and observe the
          locations it reports for the pci frame buffers. Use these for the
          hex address parameters

        2.If you don't know many megabytes to use for the size parameters
          then 16 is a good default value.


?About this file :
This is a supplement to the k6wc.exe readme file and relates to modifications
made to the new k6wcx.exe program. Please read the k6wc.exe documentation in
the file "readme.txt" first.

Summary:
k6wcx.exe is basically the same as k6wc.exe except that you specify the
size of the write combining ranges in 128KB blocks instead of whole megbytes.
It is particularly useful for enabling write combining for your legacy VGA
memory (see the last FAQ).


FAQ:
Q. Why are 2 programs (k6wc.exe and k6wcx.exe) needed to enable write combining?

A. They aren't both needed. You can use either. k6wc.exe is the original
   program and I simply added one new feature to k6wcx.exe. I left k6wc.exe
   as it was because for some people the original program will be easier to use.


Q. So how is k6wcx.exe different from k6wc.exe?

A. Very simply, k6wcx.exe expects the size of the wite combining range to be
   specified in 128K blocks (one eigth of a megaybte blocks) rather than in
   whole megabytes as was the case with k6wc.exe. Apart from how you specify
   the size of the write combining range the two programs are identical.
   
   For example the commands,
    "k6wc e8000000 4 ec000000 8"
   and
    "k6wcx e8000000 32 ec000000 64"
   would both do exactly the same job. They would both enable one 4MB write
   combining range starting at address e8000000 and another 8MB write combining
   range starting at address ec000000.


Q. Why would you use k6wcx.exe instead of k6wc.exe?

A. If you want to enable a fractional megabyte write combining range.
   For most "linear frame buffers" (pci frame buffers) this is not needed.
   One particular case where k6wcx is useful however is for enabling
   write conbining on the "legacy" VGA memory. This is a 128KB range starting
   at address A0000 (000A0000). For example on my computer I only have the one
   pci frame buffer (at address E0000000). The AMD k6-2/3 provide for two write
   combining ranges, so I make use of the second available write combining range
   by enabling write combining on the legacy VGA memory. So in my autoexec.bat
   file I have the following command (without the quotes),
   "k6wcx e0000000 128 a0000 1".
   This sets up one 16MB (128/8 MB) range at address e0000000 and another
   128KB (1/8 MB) range at a0000.