Info Guide #02

Железо

Pentagon - Instructions for remaking the Spectrum for the entire screen.

  AlCo


   Immediately I ask out of my head the whole
that nonsense, which I shipped in the last issue ... As 
explained to me, short legs on the chips is not good, they can 
from this deteriorate ... Based on these data publish the final 
result of my experiments over the scheme display the Pentagon. 

   Thus,

            Contact v2.03!


   Goals that I pursued were the following: allow the use of 
the entire area screen, including the curb, not adding to the 
scheme computer or a single chip; release

processor from toil in the switching / moving screen buffers 
used in all of this serial double switch for on / off obtained 
ruleza. 

   But what should we do first? Naturally, finding a signal curb
(Here is a characteristic plot charts) ...


                           D10

           D9 +5 v 13
1 B3 4 ___ <oR T
2 B4 'BOR June 1912 Q
4 B5 5 x D
Aug. 1 / C _ C5

                       11 Q
> B1 oS

                      10 C6


... And cut it (which put a cross).
Naturally, this should be done when the computer is off:). 
Rulez first will be seen when you turn on your computer: No, 
not characteristic of the smoke, but that edge will disappear 
and his place will see the following things:




         d a b c d b

        ___ ___


         d A B C D b

        ___ ___ ___ ___ ___ ___


         h E F G H f

        ___ ___ ___ ___ ___ ___


         l I J K L j

        ___ ___


              dirt every



   This is mainly a repetition of already existing images. The 
lower part is read from Address # 5800, and attributes to it - 
with addresses # 5B00. (From this it follows that as long as it 
can not be used.) 

   For a start, and it's not bad. I even wrote
scrolling across the screen, switching
with the insane speed (and a jeweler's precision) screen buffer.

   You can, of course, to entrust it to automation,
filing, such as former signal curb instead of numbers on the 
screen 13/D17. But, believe me me, it's a dead-end path.


   Let's find out, what does is signal to the curb:
 000000
 111111
 111111 D9
 ___ 111 ​​111 4 000 000
 000,000 '6 BOR 011110

            5 011110
 011110 011110
 011110 000000
 011110 LI1
 011110
 011110

   So, the signal from the fourth leg we serve ... uh-uh ... on 
what is the address of the file? 

   Let's enter a name for all addresses (no addresses of the 
processor and the device address inputs of memory management - 
Whoop): 


   A0, A1, A2, A3, A4, A5, A6, A7,

   A8, A9, A10, A11, A12, A13,

   P0, P1, P2.


   Signals P0-P2 - it's in the usual sense
Bits number pages to which we turn. Signals A0-A12 is used. On
page set one's bag for as long as we will not. Remains
A13. Or rather - A13V, t.e.tot A13, which
served on Whoop Video Controller (D16-D17),
Unlike Whoop Processor (D18-D19). Normally, A13V hangs on 
earth. And our message to field on the main screen - a unit. 
Have to put the switch:


     ___

     BOR in ___

                   BOR out

        +5 V

       (<)


                A13V (11/D17)

     4/D9



   Now the central portion of the screen will
read from the address # 6000, and that at the edges,
will remain at the old location # 4000.

   I think we all? And here and there! After all, the top third 
is still duplicated, and at the bottom - the attributes and 
mask are read from a the same mesta.Posmotrim again at the 
scheme Pentagon and find the signal P0V (14/D17), at

who received 5 v.Nashli? So, these five
we cut the current (cutting mat those who held this track under 
the chip) and Deputy They kinematic signal 5/D9. What we got:



 4-th page # C018 # E000 # C008 4-th page

            ____ ____


           # 4018 # 6000 # 4008


 4-th page # D818 # F800 # D808 4-th page



   It remains to make the final leap: untie address attributes 
and a mask from each other so that the bottom third was can be 
used not only to attribute scrolls. Locate the circuit 
multiplexer, which commutes these addresses: 


                D14


  B12 2 A0

  B13 5 A1 Y0 4 B14 (A8V)

  +5 V 11 A2

   <14 A3 Y1 7 B15 (A9V)

  B6 3 B0

  B7 6 B1 Y2 9 B16 (A10V)

  B8 1910 B2

  B12 13 B3 Y3 12 B17 (A11V)

               KP11

  C30 1 V


          15 W



   Cut off the +5 v from 14/D14 (be careful not to cut off 
power in the chip itself) and serve in his place all the same 
signal 5/D9. Everything! Now the attributes in the top

and the lowest thirds are taken not on the basis of "all the 
attributes are stored at addresses 4-th third, and the rate of 
"all the attributes are stored at 2 nd third, "that is, for the 
upper third of the addresses and # D000 # F000, but for the 
bottom - # D300 and # F300.Razumeetsya in 4-th page of RAM. 

   The second screen can also be used -
He scattered through the 7 th and 6 th page.

   Keanu, eh, you Junk source listalki to 80 characters per 
line (LISTER80.H). And maybe even write something, too, Toda 
kin.