MADROM

There were questions about installing the subject. One of these days it will be thrown into ZX.SPECTRUM with help.
If anyone is not subscribed to it, or if something doesn’t work out, complain asap!
Questions/reviews - here. I will subscribe to that echo only for one day.

In the meantime, here it is:

╒═════════ MAD_inst.W ════════════──

MADROM is a program that flashed into page
A15="0", A14="0" ROM 27512 (D36). Those. to a separate page:
"0" and "1" - TR-DOS,
"1" and "0" - Basic-128 or NeOS,
"1" and "1" - Basic-48.

In different computers you can get to this page in different ways.
In the Pentagon this is probably the most difficult. :) To get
to the service page you need to do the following:

Cut off legs 11 and 12 of D76 from +5V. Apply GND to the 12th, and connect the 11th as follows:

/RESET ──┤>├─┬── to 11n.D76
KD522 │
+5B ──███─┤
10K │
/ enter the service page.
│
═╧═

and 4n.D82 apply “1”, freeing it first (or
exclude this element from the circuit altogether by applying immediately from
8n.D77 to 10n.D76). From 12n.D62 we feed it to 27n.D36, cut off the old signal from 27n.D36. and 1n.D36, having previously released it
, we serve directly with 9n.D76.

and Leningrad-clones putcontrollers are very capable,
so it’s quite
difficult to say anything definite here. but usually one diode is enough for everything
to work as expected.

The point is that when you press the button, RESET goes through and
simultaneously _turns on_DOS_.

╘═════════ end of file ════════════──

All the best.
Sincerely, Roman.