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*		   Falcon MC68040 CPU ToolKit v5.00			* 
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DMASNOOP.PRG
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Description:
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DMASNOOP is a special patch which can be used in conjunction with the
TKROMDRV ToolKit driver to fix a whole host of problems connected with
floppy disk, SCSI drives, CD-ROM's & scanners and many other such SCSI
and/or DMA based peripherals. The ToolKit driver fixes a great many of
these problems on it's own, but there are special situations where some
device drivers or disk cacheing programs try to be a bit too smart and
manage to get around the ToolKit's internal DMA counter-measures.

If you are having nasty problems with disk errors and/or difficulty
reading or writing or accessing one of your SCSI or otherwise DMA based
peripherals, and you have found that disabling the CPU data cache is the
only way to cure the problems, then DMASNOOP is very probably the answer
to your problem.


Installation:
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Simply place DMASNOOP.PRG just after the TKROMDRV.PRG and perform a cold
boot (CTRL-ALT-SHIFT-DEL). When the machine has rebooted, you should find
your device problems have cleared up.


Important details:
------------------

DMASNOOP has some 'side effects', which are not normally a problem, but
it is better to know what they are in case they lead to confusion at
some later date. Any programs loaded into ST-RAM *after* DMASNOOP in the
autofolder (or on the desktop - it doesn't matter) will effectively run
with the CPU caches turned off, even though the caches are still really
turned on. This is because DMASNOOP changes all free ST-RAM into non-
cacheable RAM, and although this is generally very good news for the
kind of programs which need ST-RAM for DMA transfers, it is very bad for
running the program code itself. It can slow things down a lot. The only
way to avoid slowdown problems with DMASNOOP is to run as much software
from FastRAM as possible (which is always cacheable and therefore is not
affected). Remember that it is only programs running AFTER DMASNOOP that
can suffer if executed from ST-RAM. Anything installed *before* DMASNOOP
will not be adversely affected in any way!.

To recap, only programs which agree with all of the following points are
at risk of running 'slowly' due to DMASNOOP:

a) Only programs which run *after* DMASNOOP is installed.
b) Only programs with the 'TT-prg' (or 'run-from-fastram') flag cleared.

All other software can only ever benefit from DMASNOOP, or will remain
totally unaffected!


Known applications:
-------------------

For reference, here are some programs which are known to benefit from the
DMASNOOP patch when SCSI devices are present:

* TCACHE6?.PRG (when 'malloc-from-fastram' flag is cleared).
* Some harddisk drivers (when run from the auto folder).
* Some SCSI CD-ROM device drivers (when TKROMDRV isn't enough).

If you have no problems with SCSI or other DMA devices using TKROMDRV on
it's own, then you can probably survive without needing DMASNOOP.


Installation details:
---------------------

DMASNOOP can only be run after TKROMDRV - an the sooner afterwards the
better. DMASNOOP can only 'help' programs which are run *after* it and
which rely on ST-RAM for DMA transfers, so running DMASNOOP last in the
auto folder is not a good idea when some of the auto folder programs
could be responsible for your disk problems in the first place!

A good, reliable auto-folder order should start like this:

XBOOT.PRG	(or your favourite boot manager)
TKROMDRV.PRG
DMASNOOP.PRG
68882.PRG