Pasti.Dll	beta release		pasti.fxatari.com

Copyright (c) 2004 by Jorge Cwik

Pasti is a software package consisting of imaging and preservation tools 
for Atari ST software.

Pasti.Dll is the emulation helper tool. It extends Atari ST emulators, 
adding support for extended disk images. These disk images support exotic, 
custom, and copy-protected formats. You can now use emulators to run ST 
software in its original uncracked form.

Pasti.Dll is almost completely transparent to the user. All the work is 
performed behind the scenes interacting between Pasti and the emulator. You 
must use an emulator with Pasti support. Pasti Dll is useless and will not 
be activated if the emulator itself is not Pasti aware. The most popular ST 
emulators already have, or will have soon, support for Pasti.

The Dll should normally installed in the same root directory that the 
emulator is installed. Depending on the emulator, Pasti will be enabled 
automatically or it must be enabled on some of the emulator configuration 
menus or dialogs. You won't be able to run Pasti images if Pasti is not 
enabled. Besides Pasti images, the Dll supports standard images in MSA and 
ST format.


Pasti.Dll configuration.

For most cases Pasti can be run with the default configuration. For the 
advanced user, detailed configuration of Pasti is available. The emulator 
will bring access to the Pasti configuration dialog on some of its 
configuration menus.

The Pasti configuration dialog has three panes. There are panes for 
configuring disk emulation speed, options and warnings.

The most interesting configuration aspect is emulation speed. There is a 
trade off between speed and accuracy. At maximum accuracy Pasti emulates 
disk access exactly as in a real machine. At maximum speed disk access is 
almost instantaneously. The more accurate is obviously the more compatible, 
but also the slower.

For most cases you will only use the two extreme options, either max 
accuracy or max speed. But many options in between are available. You can 
configure individually each aspect of disk emulation.


Pasti options

"Fake Write Protect"

When this option is enabled and the image is loaded as read only, Pasti 
"lies" to the software making it to believe that the disk is not write 
protected. Some programs refuse to run if the disk is write protected, even 
though they will never write to the disk. This option is very useful for 
these cases. Note that this option doesn't change the actual write protect 
status; any actual attempt to write to the disk will fail.

"Disable Randomize"

A floppy drive is an imprecise mechanical device, timings are not very 
accurate or constant. By default Pasti introduces some small randomization 
to mimic this behavior. Check this option to disable it. The small 
variations of disk timing are used by some software as a random number 
generator (or more precisely, to seed the generator). Checking this option 
will make Pasti fully deterministic and might interfere with this.


Warnings

Pasti will issue a warning under some circumstances. You can enable or 
disable all of them in the warnings pane.



Steem version 3.2 specifics

Steem 3.2 is the first version with Pasti support. You can't use Pasti with 
previous Steem versions.

The most important Pasti options are available at the Disk Manager Options 
menu. Once you enable Pasti on this menu by selecting "Use Pasti", Pasti 
will be activated. Clicking on "Pasti Configuratin" will bring the Pasti 
configuration dialog.

The debug build of Steem has additional Pasti options. The "Pasti Status" 
dialog is available from the "Browsers" submenu, and the "Pasti 
Breakpoints" dialog at the Breakpoints one.

All pasti configuration options, except Pasti Breakpoints are saved across 
Steem sessions.


Debugging and monitoring tools.

These tools are available with the emulator debugger. They are intended for 
the advanced user. Some minimal knowledge of ST and FDC programming is 
required. Some emulators have a separate debug build. In those cases these 
tools will not be available in the normal build.

Pasti Status

This dialog shows the current state of the drives and FDC and DMA 
registers.


Pasti Breakpoints

Pasti implements breakpoint at the FDC level. You can specify conditions 
for a breakpoint to be triggered. A breakpoint is triggered when all the 
conditions match at the time that the FDC Command register is written. 
Conditions are available for all the FDC registers and other hardware 
registers.

Some conditions are selected using a value/mask pair, and a range of values 
is used for others.
 
For value/mask settings, the condition matches when the "current register 
state" AND "mask" equal the "value". For range settings, the condition 
matches when the "current register" is higher or same than the "minimum" 
and lower or same than the "maximum".

If you want to ignore a specific register, so that the breakpoint will be 
triggered no matters the state of this register, use a mask of 0 or the 
maximum range (0 - ff).



Saint specifics

Saint 1.85 is the first version with Pasti support. You can't use Pasti 
with previous Saint versions.

Currently Saint doesn't provide user access to the Pasti dialogs. All Pasti 
options are handled internally by Saint.



Release notes

This is a beta release. Currently there are two major limitations.

Save and load state (sometimes known as memory snapshot) is partially 
implemented. Specifically, save state can't be performed while a FDC 
operation is in progress. States are version specific, you can't load a 
state saved with a different version of Pasti.Dll

Writes to Pasti images are lost and discarded on eject. You can write to 
the in memory image if the image is not loaded as read only. But the actual 
disk image file will not be modified. This affect Pasti images only. 
Writing to ST and MSA image files is fully implemented.


LEGAL

Pasti.Dll is copyright (c) 2004 by Jorge Cwik.

This software is provided as is. No warranty of any kind is given or 
implied.


Pasti.Dll 	beta release		pasti.fxatari.com

