Suddenly it will come in handy - Scheme for eliminating the conflict between the #FF port and the modem (#EF) in GRM.

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║  What if it comes in handy?        ║
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(C) EVP-SOFT

 Hello everyone. After two weeks of annoying meMULTISOFTom
on the topic of eliminating the conflict between the #FF port and the modem in GRM
(#EF), I finally drew the corresponding diagram (Fig. 1).And
so, this circuit blocks port #FF if the address line is reset
A4 (i.e. the modem is selected). First
it is necessary to cut the path coming from  1┌────┐
12 pins m/s ID7 (D56 - old  FFRD ──────────┤ │3
GRM / D58 - new); then in her  5┌────┐6 2│LL1 ├─ FFRD'
gap enable FFRD (to m/s) and  A4 ─┤LN1 o───┤ │
FFRD'(to track). A4 can be taken from  └────┘ └────┘
34 Z-80 pins.  On the GRM board  Fig.1
there is onefree element in LN1,
this is which D61 - old GRM / D63 - new GRM, pins 5 and 6 - in
This is exactly the scheme that will be used. And check the diagram
simple - type in BASIC (without a modem, of course):

10 PRINT AT 0,0;IN 239;" ";:GO TO 10

if port #FF no longer conflicts with the modem, then on the screen
will always be "255", and to make sure that port #FF is working,
dial:

10 PRINT AT 0,0;IN 255;" ";:GO TO 10

and on the screen there will be not 255, but mainly the screen attribute code.

 * * *

 Many people try to connect the drive EPSON SMD-300 to the Spectrum,
(for those who don’t know, this is 3.5", 1.44). And you can usually connect it,
only it doesn't work :( ┌───┬───┬───┬───┬───┬───────┬───┐
because it is necessary to correctly high-│ G │ A │ A │ T │ I │ 0 * │ 1 │
place jumpers on it. Their├───┼───┤ ├───┼───┼───┬───┼───┤
you only need to leave two, and │ H │ * │ L │ S │ * │ 2 │ * │ 3 │
put it asshown on └───┴───┴───┴───┴───┴───┴───┴───┘
Fig.2.  In this example, disco  Fig. 2
water is selected as "A" ("0"+"*"), but to select it, for example,
as "D" you need to place this jumper between "3" and "*". I already have
Two of these drives have been installed for a year, and so far there are no problems.