HARDWARE - Mode switch Profi / Pentagon.

Echo #03

                Hardware



   (C) Falcon / Atlanta h. g.

   specifically for the ECHO.


   Two in one, or you want to be happy - be happy! "


   And this revision is designed to nearly
lucky owners of laptop models
"Profi". Almost - because in spite of
All appeals of wider support advanced
Memory of the existing computer models
they do not find much response from the programmers. A number 
of programs that support extended memory standard 
"Pentagon"-and by bits D6-D7 port # 7FFD, everything grows. In 
this regard, I have developed and put yourself into the 
computer a little refinement, allowing further does not 
particularly think about this problem. 


   Finalization of a switch to "Profi / Pentagon", which allows
work as in the usual "Profi" mode and control mode pamatyu 
through bits D6-D7 port # 7FFD. When translating mode 
"Pentagon-512 additional memory pages at once included in the 
address space, even when locked additional switch ports (switch 
ON / OFF), memory above 512K in this case is not supported.



   Required for completion of 2 chips: TM9 and KP11 series 
555/1533. The board Cutting the track between the 15U23 and 
13U60, 10U23 and 3U60. IC D1 'is convenient to install the 
system on the old port of U58, when This pins 1, 8, 9, 16, 
leave as is, while the rest turn down. D2'-at any

convenient place on the board. With the rest I hope is clear - 
act in accordance with the scheme. 


   Legend chips are given according to the scheme "Profi" v3. 
2, and at the same model made the installation and testing. 



            D1 'D2'

      3 2 2

  D6 

      4 D3 Q3 May 5 A2

         D4 Q4 A3 Y1>

         D5 Q5 July 3

         D6 Q6 15U23  13U60


   -> 3U60

   7



   Falcon / Atlanta h. g.

   Andrew Panyutich

   225140 Belarus, Brest region.

   g.Pruzhany Str. Vashkevich, 4, kv.42.

   phone 8 + (01632) 2-13-90