Incompatibilities and possible technical problems:
===========================================================================

1) DPMI server HDPMI32
---------------------
For its work, Bloček needs a memory manager called DPMI server. It can be
provided by the Windows kernel or an external program in case when running from
DOS. The default DPMI server is CWSDPMI which is included in the distribution 
archive. However, you can start an alternative DPMI server and Bloček will use
it instead.
One of such popular DPMI servers is HDPMI32 which is included in the HX-DOS
package by Japheth. 
Bloček can certainly work with this server, but there's one pitfall. You can set
various parameters of this server using the HDPMI environment variable.
There's an incompatibility between set fifth bit of the HDPMI variable (like
HDPMI=32).
This setting separates parent's and child's memory regions when the parent calls
the child process.
In Bloček, this technique is used by the QR code generator. With this setting, 
it won't work.


2) Mouse driver
---------------
During initialization, Bloček follows the DOS programming recommendation and
before using any mouse function, it checks whether the mouse is properly
installed. If not, Bloček will refuse to run.
Unfortunately, this test can be sometimes misleading and the mouse driver
reports an error even if the mouse is usable. It can happen e.g. after a
previous program which uses the mouse crashes.
If that's the case, open the configuration file BLOCEK.CFG and edit the
parameter "ruzne_sys_priznaky = ..." to use an uppercase B


3) Keyboard driver
------------------
Bloček as a DOS program uses the DOS (and BIOS) services to handle the 
keyboard events. But it can use its own keyboard layout simultaneously, so it
can behave differently.
It is important that Bloček cooperates with the BIOS/DOS driver even in their
own layout mode.
In some situations, some conflicts can occur. Main problem are the so called 
"dead keys" used by some drivers for certain non english languages. They're used
as a prefix for next keys.
They're processed by the BIOS/DOS driver in a non-transparent way and it is 
difficult to solve the situations when DOS thinks that the "dead key" was
pressed, but our scheme uses the key as a normal key.
Example: We have a DOS Czech driver which has mapped the dead key
(prefix key for carron) to key +/=
But in Bloček we use the built in Russian layout. Accordingly the Russian 
layout the +/= key is just a normal key for +/=
Bloček tries to solve such conflicts but it can be always 100% reliable.
It's better to use Bloček without any DOS keyboard layouts containing dead keys.
   Since version 1.74, two keyboard processing routines are available.
   The new one (and default one) is based on the BIOS interrupt 15h/AH=4Fh and
   the older one is based on the BIOS interrupt 9h. The new one should cooperate
   better with the DOS kernel and the DOS drivers, but in several situations 
   (mainly when running under debuggers) the older routine can be better.
   To select the desired routine, open the BLOCEK.CFG file and edit the line
   beginning with "ruzne_sys_priznaky=abcde"
   To select the old handler change the letter "e" to "E"
   (ruzne_sys_priznaky=abcdE)


4) Link between Bloček Clipboard #7 and MS Windows Clipboard
--------------------------------------------------------------------------
If you see the indicator "7W" instead of "7", it means that the API is 
available allowing access to Windows clipboard from DOS programs. 
This API is called WinOldApp and it is accessible from Windows 3.1, 95, 98 
and ME. There are also some DOS TSRs compatible with this standard and some 
versions of DOSBox (e.g. DOSBox-X) can use this interface.
In such case, when pressing CTRL-7, the text block is copied also to the 
Windows clipboard where it's available to other programs.
Analogically, Bloček watches the state of the Windows clipboard and text is 
detected, it signalizes that.
There is a limitation, though. Although the native MS Windows programs can
use Unicode transfers to and from the buffer, it is not available to DOS.
So all Unicode text from Windows inside the WinOldApp API is converted to 
DOS OEM page so the Unicode characters not in that code page will not be 
transferred correctly.


5) VGA fonts from video card and from disk files
--------------------------------------------------------------------------
By default Bloček during videomode initialization scans the video card and
downloads the VGA fonts from RAM memory. This is very flexible however on
some configurations it can take more time than expected and your monitor can
switch off for few seconds. The reason is the multiple video mode switching
during this process. Most of video cards and monitors don't have any problem
with that, however on other cards can be the mode switch a little bit time
consuming.
For these situations you can use the different way how to get VGA fonts - not
from hardware but from font files in .FV or .WFV format.
Look into BLOCEK.CFG and look for parameter "vga_fonts".
If this parameter is set to "vga", "hw" or "hardware" it uses the hardware fonts.
But if you specify three font files for sizes 8, 14, and 16px, Bloček will
use them and will not use the downloading from hardware and the videomode
switches.
However, if your bottle neck is not the speed of videomode setting but the disk
access speed, it can slow down the program initialization.

