And again about KEMPST0N M0USE - a very simple circuit.

And again about KEMPST0N M0USE.                                      
                                                                
WARL0CK 02/17/97                                               
                                                                
 Seeing the "HARDWARE" section, you probably thought that this was CRAZY again
ALEX, but I hasten to disappoint you, this is not so, this article was written
me, i.e.  WARL0CKom.  Here I will give a very simple diagram,
which is intended for users of a device called
Kempston Mouse, for which the program does not detect the presence
of this device. This happens on those computers that have
when reading from port b4223, i.e. mouse button port, not readable
255 (this is how the mouse is determined in ZX-FORMATe). For example: at
I don’t have a mouse, but the port reads consistently 255 and higher
The named log identifies this device for me.  Below
the above diagram when selecting port b4223 sets the higher
five bits per unit, and if you have a mouse then - (at least
least ZX-FORMATom) it will be determined.                              
                                                                
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 And now to the diagram itself:┌──────>+5V                           
                          │                                     
         ┌─┬───┐DD1.1 │ ┌───────────────┐           
  A8 ───1┤D│ ○├3┐ ┌─┴─┐ R4 │ ┌──┬──┬──┐ │           
 A10 ───2┤E│ │ │ │ └─████──┼──3┤D0│RG│ │ │           
         └─┴───┘ │ R1 │ ├──4┤D1│ │Q0├2─┤           
      ┌──────────┴─████─┤ ├──7┤D2│ │Q1├5─┤           
      │ ┌─┬───┐DD1.2 │ ├──8┤D3│ │Q2├b─┘           
      └─4┤D│ ○├b┐ │ ├─13┤D4│ │Q3├9────D3       
  A5 ───5┤E│ │ │ │ ├─14┤D5│ │Q4├12───D4       
         └─┴───┘ │ R2 │ ├─17┤Db│ │Q5├15───D5       
      ┌──────────┴─████─┤ ├─18┤D7│ │Qb├1b───Db       
      │ ┌─┬───┐DD1.3 │ │ ├──┤ │Q7├19───D7       
 ____ └─9┤D│ ○├8┐ │ └─11┤E, and if it is not log.0, then the output of the microcircuit goes to
Z-state.  Exactly the same latches are located at the output of IR22.
In my opinion, the circuit couldn’t be simpler, if assembled correctly during setup
Absolutely no need. CRAZY ALEXom and I checked this scheme
on his computer - he plows like a beast, and the ZX-FORMATom mouse is detected
(by the way, CRAZY has a mouseALEXa thanks to this magazine, details
read in the sixth issue of HACKERa).                              
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 CRAZY ALEX: I must also add that this problem can be solved
even simpler.  The fact is that PROFI has a scheme
maintenance of the notorious #FF port (damn it thrice...)
and for this reason from any unused port on PROFI
either pixels or attributes are read, well, in short, all sorts of crap
which is supposedly needed for some branded left-wing programs. Well
So, closer to the memory chips on the bottom PROFI+ board
there are 8 resistors. If you remove them, then you have more #FF port
will not be and will be read from any unused port
clear 255. But if you value this #FF port, I recommend
assemble the above diagram. By the way, I don't know how things are
on other PROFIs, since I have PROFI+ with black and white CP/M.      
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