Spectrofon #16 20 декабря 1995

Железо     Scorpion ZS     Profi

Designer - Universal decoding scheme expansion ports for machines with additional memory. Comparison of computer "PROFI" and "SCORPION".

         DESIGNER



   We are opening a new chapter in
which will publish articles
a hardware issue. Increased
a stream of letters from both the authors of the new
hardware development, and on
novice users
"ZX-SPECTRUM" allows you to make
concluded that the old Speccy, it seems, finds our country a 
second youth. 

   In this to your attention the article discusses the 
compatibility issues of different classes of machines with more 
memory (in particular, ATM-Turbo and "Professional"), is

version of the circuit design of a universal decoder system
port, which allows to
access to available memory
address to the port on any of the
two addresses. The article also covers the issue of conflicts 
of registers expansion port # FD, often used to control the 
configuration of your computer. This scheme is decryption

virtually eliminates the likelihood of an erroneous situation, 
resulting from collisions. 



(C) A. Titov, R. Akmalov (Izhevsk)


      UNIVERSAL SCHEME
Decoding PORT EXPANSION FOR
 MACHINES WITH MORE MEMORY


   For a start I would like to say what the reasons prompted 
the authors to study this area. In recent years, the market 
Spectrum-compatible computers had some

fundamentally new models with much more capabilities than
with a standard machine. The number
their advantages include a large
RAM (up to 1 MB in the ATM-Turbo
2 +, and "Professional"). There was a software that supports 
this memory. 



   While most of these programs are focused on work in
specific environment, there
opportunity to use the advanced resources of the Sinclair-mode, 
as do, for example, Honey Commander, PSW boot,

Conver and other means. Together
so there is no
standard access methods
extended memory, which vary greatly from model to
model. Address this discrepancy, as shown in
Further, extremely simple.


   The authors have not aimed
achieve full compliance
configuration of different computers in all modes, but allow 
for dual memory access (via one of two ports available) would 
be very desirable.


   On the other hand, ATM-Turbo and
"Professional" (as well as Scorpion 256K)
still have something in common. This
"Something" - overlapping ports
extensions to the standard configuration registers ZX-Spectrum
128K (its hexadecimal address = # xxFD: upper 8 bits are
matter). The peculiarity of this
everyone can observe, trying, for example, run
something like Insult
Megademo, Turbo Assembler, or
Stalker Stealth Monitor on
ATM-Turbo, or "Professional" with pressed
button ON / OFF. It is not an end
complaining about the stubbornness of the programmers who do 
not wish to specify full address # 7FFD when working with

pages of Spectrum-128. Much more efficient
means of dealing with the incompatibility is the way set out in 
Chapter 2 of this article. 

   With the help of a pair of chips can avoid the complexities 
associated with the work of these programs (And not only them).




            Chapter I


   First, some theoretical information. As is well known
from the literature, the register address
configuration of Profi "= # DFFD (in
scheme it is commonly referred to CMR1),
port address of the memory access
ATM-Turbo = # FDFD. In the binary
as the high bytes of address
as follows:


     # DF # FD

  11011111 11111101
 (Bit A13 = 0) (bits A9 = 0)



   Due to the presence in each byte
just dropped by 1 bit, decoding of such addresses is simple. In
"Professional" She made the following
way (for version 3.02):


A1 1 ON S
A13



   Signal S is 1 if oba
A1 and A13 bits are reset, ie if the address bus exposed
Address # DFFD (in fact it is obvious that this is not true, but
more on that later). In this case,
byte data bus is taken
expansion port "Professional". If
at least one of the bits A1, A13
installed, the sample port is prohibited.



   Now suppose that we wish to change your registry 
configuration # FDFD (port ATM-Turbo). Clearly, for

it suffices to replace in the above diagram signal A13 to the 
A9. But from a practical point of view

more sense circuit, permitting the sample port when putting up 
the address bus of a (Any) of the addresses # DFFD,

# FDFD. Then the program, including the pages through one of 
these registers would work without additional switching 
signals, of course, if the computer has 512K of RAM

or more. Such a scheme, thanks to the efforts of Rustam, has 
turned not much more complicated an existing one.

That is what is her idea:



   A1 1 ON S

   A13 X



              DD1.1 DD2.1


                = 1 A

   A9

"X" - the gap

DD1 - K1533LP5, DD2 - K1533L1


   It is easy to see that if the bits
A9 and A13 are equal (not selected any
one of the ports # DFFD, # FDFD),
signal which is fed to the input
OR element instead of the A13, will be
set to 1 by inhibiting the sample
port. If the signals are different
(A9 = 0, A13 = 1 and A9 = 1, A13 = 0)
instead of cut A13 go
0 and case work.

   For programs that are running
TR-DOS, this scheme is quite enough (no masking of bits of the 
port ATM-Turbo, not involved in the selection of the page).

Similarly, the scheme can be completed decoding port
PC ATM-Turbo, and quite
possible, Scorpion-256 (although
the latter case, it is likely
is somewhat more complicated, for
As of this writing scheme
computer was missing from the authors). It must be noted that
these machines, the proposed scheme
tested by the authors was not.


   After the above refinement
on my "Professional" trouble-free Honey Commander 3.04,
identifying startup availability
RAM-disk capacity of 412K.



   It remains to add that blocking the port expansion button
ON / OFF does not change its
action as a result made
changes.



            Chapter II


   First things first, let me
explain the principles of the port
# FD. So, as mentioned above, meaningless bits of address
this port are the lower 8
bits. This means that the output
information on ports # 00FD,
# 01FD, ... , # FFFD for standard leads to the Spectrum
the same result.
That is why the boot configuration register can use the OUT (# 
FD), A, which is known, gives

the contents of the battery to the external port, having an 
address, junior 8 bits of which contain # FD, and

older than a specified pre-
all the same case A. In fact, when performing a command byte is 
output # xx the port with the address # xxFD.



   It is easy to imagine that
happens during a
command on a machine with an additional register extension, yea
even when the decoding scheme is so simplified that
uses only two bits of the address bus. One need only two bits 
of output to the standard port values ​​coincide with the 
corresponding two bits of high byte addresses the configuration 
register, this register will work, that would tend all, to 
disastrous results. 


   The following scheme is
neither more nor less than the maximum
the correct way to recognize a reference to the additional port
and weed out the "foreign" output (option
for the "Professional").

A1 DD1.1

A8 '
A9
A10
On the A11 S1
A12
A13
A14
A15



      DD2.1


        About

DD1: K1533LA2, DD2: K1533L1
Signal S1 is connected to the input
OR element instead of the signal A13
(See diagram in chapter I). Old
Communications from the entrance comes off.


   In this arrangement, the decoder
additional port will only respond to "your" address
(# DFFD). Theoretically, the derivation
to port # FD # DF values ​​extended register still works,
but it should be noted that this
value has enabled
Bits 6 and 7, which are usually dumped in the formation of bytes
configuration for the transfer to the port
# FD.


   Similarly, we can modify the scheme or the ATM-Turbo
Scorpion 256K, of course, given the particular implementation 
of the decoder port. 


   The authors after
Revised the "pros" with pressed
ON / OFF button and run by without
bugs worked Insult
Megademo, as well as several
"Intros" M. Iwamoto, known
its "intransigence" on port
# DFFD.



             Summary


   Below is a summary diagram
decoder, which combines
dignity of the previous two (see
Chapter I, II).



       A DD1.1
A8 '

       2
A10

       3
On the A11 S1

       4
A12

       5


       6
A14

      11
A15

      12



   10k DD3.1 DD2.1
+5 1 3 1 2
A13 = 1, O

       2
A9

DD1: K1533LA2, DD2: K1533L1,
DD3: K1533LP5


   The scheme was tested
on "Professional" version 3.02 with 1 MB
RAM. Theoretically it should work on ATM-Turbo without 
fundamental changes. Due to the nature decoding port Computer 
Scorpion ZS256 application of the method described in resolve 
conflicts, most likely, is difficult. 

Contacts: 426006, city of
Izhevsk, ul. Club, 65-59, Alexey Titov. tel. (3412)
71-84-84.


            *



(C) Leonid Potekhin


   I want to say a few words about
the problem is not so serious but still unpleasant enough. 
Probably many have noticed that not all machines perform the 
same number of operations between two interrupts. Case

not that there is no synchronization
any type of special effects HIDDEN
PART FROM INSULT MEGADEMO, the problem is that this part of
INSULT'a, and as part of the STAR
WARS of SATISFACTION and some
others heaped up programs are not
fit into one interrupt and
terribly slow down. Especially distinguished SCORPION'y. But 
not only they are like. Although at

the same normal all pentagons
works great.



   By the way, the program FUT 2.01
(Author D. Alnbregin and
M. Kondrat) is integrated test
computer performance and well-noticeable difference in speed.


   In order to correct
this is for SCORPION'a, must
cut the jumper in the third
from quartz chip, the width of the
board and ground vacated
leg of the chip. But for
Scorpion with a professional
extension ROM, will put the switch because in this
"Accelerated" mode for some reason not
passes the initial testing.

P.S. I've heard that in Moscow organized by the club Scorpion, 
would not mind them contact, since I myself am

such. For anyone who wants to
contact me on
Scorpion:

610004, Kirov, Naberezhnaya street
Green, 1, kv.43 Potekhin Leonid. (8332) 69-28-26



             / X 5V

      Connect with the earth.
(C) Kirill Gromov


          Done!


   As I already wrote earlier, I had
work on changing work
reference sync computer
"PROS". So please hurry - the work a success! Now the details. 
Initially there was a sync versions boards 3.xx, it is perhaps 
the most dismal creature, and sharpen the focus on it I do not

I will. Let me just say that to recognize
This version can be black
frame around the screen SPECTRUM and
Playing QARX letters do not run
on top of the curb, and
somewhere in the middle of the screen. Then
the specialists of "Condor" are written version was "SAMX6" in
which was implemented SPECTRUM full screen, plus the correct 
formation of the signal INT. And though like everything was 
normal, I was not satisfied with the position of the upper curb 
effects. The idea that there is "guilty"

INT proved to be incorrect, the case was in the conversion of 
strings. As we know, right "deploy" 312 rows SPECTRUM

raster (screen + border). In many schemes, such as the "Pentagon
128 ", is computed 320 lines -
This leads to an apparent violation of
synchronization. The most noticeable
if it is from BASICa give a command "SAVE" - instead of clearly 
visible rising on the curb bands will be visible to the chaotic

mishmash. In "Profiles" things were almost as expected, only
counting eight cycles (16 * 19 + 8
= 312) occurred in personnel
momentum, rather than before them.

This led to the fact that the formation of the screen starts at 
8 lines before and looked

as if the image on the curb
"Launched" on one of familiarity.
Although "SHOCK MEGADEMO" was decent enough, the sprites are 
not disappearing. So the first problem point was the position 
calculation. Here is the first moment I removed the. And then 
turned Funny thing, the picture on the screen / curb were 
poured as a "The Pentagon 128" with modified

INTom that led me to believe
that the "PROS" versions 3.xx - 4.xx
nothing more than an improved and feature-rich "Pentagon"! True
only on the bus and makeshift. Looking ahead to say that this 
is important signal WAIT, in "Pentagon" and the old "PROS" he

simply not used. So
get a version of "SAMX6M".
Well going SHOCKom, unfortunately, had to sacrifice. But
finally fell into place
upper curb the effects and
went to "multicolor" in firm
programs. The second point that I was depressed was the fact
that was evident in QARXe move the beam
forms the border in the right
top right corner. Practice has shown
that here the key role played
duration of the signal INT. And
which again is ridiculous, the duration
chosen exactly as in the corporate SPECCY here was not
optimal. Probably due to many parameters of the circuit computer
shorter INT processed in exactly the same as strictly
Fixed INT in the company
SPECCY.



   By the way, is that INT is formed at the beginning of the 
frame (that is, trailing edge of an inverted human clock) is 
not quite true. In fact, he formed a little earlier. This 
conclusion I have drawn from the fact that scheme realizing the 
principle described above is given in the program ACADEMY 
following effect - curbs the image is shifted relative to the 
screen in left upper right corner of exactly one pixel. This 
time I did not become clear, although it is theoretically 
possible to do. But the apparent stroke beam QARXe I almost 
eliminated, choosing the duration of the experiment INTa. Now 
the duration INTa somewhere around 8 - 8.6 ms. While in theory 
"is not is quite well "in practice

no problems with the "critical"
programs were not.

   At this moment two revised and modified version
reference sync are named
"SAM7CS" - for versions boards 3.xx
- 4.xx, and "SAM14CS" - for versions
Motherboard 5.xx. Both driver were
All measurements in the frequency and duration of the clock, 
human frame, etc., the results were good and now all

Boards will be completed with data sync.


  "Fifth" version of the fee earned
I am very pleasant surprise. For
by the fact that in the scheme of the processor signals are 
formed from WAIT video controller turned

perfect synchronization. Such
I have not seen! In all the "critical" the program is 
completely coincide ALL curb the effects, work all 
"MULTICOLOR". 

A notorious SHOCK MEGADEMO works so perfectly that I
sat spellbound for five minutes does not
believing in what is happening. There seems
impact that the use of
the latest version of the asynchronous
circuitry in the SPECTRUM mode
allowed to achieve full emulation "opaque" tire brand ZX 
SPECTRUM. All of this gives me to say that today "PROFI version 
5.03 the most successful and compatible models commercially 
available computer. Naturally the owners have already purchased 
boards All versions can apply to

me to rework their computer.



    In principle, the old "TRAC" you can try cross-connected 
WAIT as the "fifth" version, this I believe will undoubtedly 
polozhitelny result but due to the large number of

new compounds will be
very difficult task.
While the enthusiasts can do
that, at the same time moving experience for
"The Pentagon" has made happy owners of the most common 128Kb 
computer in our country.



    The main technical summary
all the above is as follows:
duration of the INT in the SPECTRUM-compatible computers are 
fixed no-one, and is chosen experimentally stable

the work of "critical" programs, no doubt so that the same 
second significance of the signal Responsible

for compatibility - it is a signal
WAIT, and there is a desire to consider how to properly 
cross-connected. The second conclusion is that: it is 
impossible to achieve 100% compatibility, and proprietary

ULA chip can proemulirovat a maximum of 99%, and then
time-consuming and tech.
means that it is unlikely the main
mass of users and producers seem to fit.

P.S. For even more compatibility, on top of the board do the 
following: 

All versions: Find in Scheme
connecting music. processor chip, where the mixed A13 and
A15, remove the foot chip
from the A13, and connect it to the A15. Y
you will go to digitized melody
(Eg, BLAVA 128).

   You can also find free
element "and" (LI1) and instead of A14
submit to the inverter and a mixture of A14
M1. This is a safety net to avoid clogging the data bus muses.
processor.

For version 5.03: Vypayayte resistor R15 on the top board, 
bridge the 2 and 3 findings m / s circuits to DD45 signal CSAP6 
(3 foot m / s circuits DD39). After that dramatically improves 
synchronization. 


 Comparison PROS "AND" Scorpio "


   As any user I
Naturally, the search reached the stage
"His" car, and did not
sorry that my choice fell on
"PROS". And now, more to the point.


I am extremely surprised that a currently wildly growing 
popularity of cars that, in spite of stopping tobacco 
advertising, obviously do not deserve the appreciation that 
they themselves pose. And same time effectively bypassed

attention is really good
computer. I want to somehow
complete this information
gap, and comparison "PROS" with the infamous "Leningrad-, oops, 
sorry," Scorpion. "To not show you pre-biased, a comparison

'll take the words taken from the book
"How to write a game for the ZX
SPECTRUM "with small reductions. So here we go:



"SCORPION (R) ZS 256 TURBO 7 MHZ"

"A complete software compatibility with computers ZX Spectrum
48/128 "


   Allow me, on a full
Compatibility can be a question
when one of the most important ports ZX128 # 7FFD not realized
as in the corporate SPECTRUM? AND
no matter what programmers refer to him not quite correct,
because it operates at the firm ZX128! "PROS" deprived of this
shortage, the port is implemented properly, all programs 
(including Such well-known as TASM and STS)

work.

"The ability to work in the OS TR-DOS,
IS-DOS, CP / M. In CP / M is supported by email. Disk

Sorry, but the work of TR-DOS and
IS-DOS is possible even on a ZX48
Controller BETA DISK. A CP / M
on the "Scorpion" globally inferior to CP / M on "profiles", as 
in "Scorpio" he does as "appendage" and the "PROS" - as a 
powerful development environment the user / programmer. What 
about email. disc comparison is as follows: volume of RAM

"Scorpion" - 256KB, "Prof" -
1Mb. It seems that every four
more.

"Unique - 'shadow'
service monitor-debugger "

Yes, it's really powerful
system, no doubt. But 'tenevatost' of this monitor to
the big question, any program running correctly with the port # 
7FFD accidentally or intentionally immediately "halt" the 
computer in the best case, worst-format the drives. 

"Turbo Mode - 7MHz. Software switchable (Warning) from
menu shadow service monitor "

About the monitor has already been said, but
Turbo Mode 7 MHz was still at the old versions of "Profiles" 
section. In posledeney same version of the mode

SPECTRUM standard for stored
Turbo mode is 7 MHz, but in the mode of CP / M rate of speed
selected and is in the range
8 - 15 MHz. All depends mainly on the processor and memory, the
I have Turbo mode - 12MHz.

"The sound processor AY-38910/12"

Sorry, but this is ridiculous.


"'Turbocharged' controller
Digital PLL "

About how this controller
"Turbocharged" have already been articles in
SPECTROFON, except to say that
this scheme, he was "turbocharged" the worst way, with all its 
consequences. A digital PLL, again, was already for "PROFILES" 
even the most ancient versions. Just been and protection

1818VG93 from failure to
nutrition.

"Intefeysy printer CENTRONICS,
RS232 "

All this is in the "profiles", more
addition, the RS232 interface is made
ALL OF THE STANDARD, which gives
can connect to it
Any pisishnye gadgets - from
"Mouse" to the modem.
"Support for the port attribute # FF"

In "Scorpion" port # FF made
wrong, one of the wrong way described in SPECTROFON 14.
It conflicts with external
devices, in particular with the modem. In "Profiles" provides
install the port # FF, and
request of the buyer specialists
Company Condor "to install it.
By the way, the most correct scheme of the port I originally
performed precisely on the "PROS"!

Snapping to the level of 'black' "

In "Profiles" this mapping and other things related to 
telestandartom (eg staffing boxes) were implemented initially 
from the earliest versions of the boards. 


"Built-in individually numbered"

Specialists of "Condor" is not
fear that they will steal them
ideas, moreover, the scheme "PROS"
completely open to the user,
allowing himself to them
develop and connect external devices. Modem easily
fit in with the "PROS" for 20 minutes.
A system connector, which we
tried to surprise the company "Scorpio" again the same was and 
is to All versions of "Profiles" section.


"IBM keyboard controller, IDE,
UV EPROM programmer "

All this is, with the corresponding
software support. A "hard drive" for "PROFILES" is already 
functioning in the month of September of the current year.

The prices of computer "PROS" commensurate with the prices of 
"Scorpio". Residents of Moscow and the surrounding areas can 
easily buy computer directly to the

firm, without paying out of pocket to various distributors / 
resellers. Quality Cards "PROFI - The highest! "SKORPIONOVSKIM 
and "NEKSTOVSKIM" to such a long way off. I just saw those and

others, so do not say this
unfounded.

Apart from the most complete compatibility mode SPECTRUM, 
characterized by (of course with the latest reference sync) 
ideal capacity for work branded programs, conservation

visuals (pictures on the curb and "MULTICOLOR"), "PROS" works 
very badly in the regime CP / M. Dealing with a P / O moves from

dead and is now among a sea of ​​software products and can be
get lost! So that the user
the right to do now is your right choice.

"S": Attention owners of computers "SCORPION"! Published
article in defense of the "PROS" reflect
personal opinion one of the owners of this brand machines. For
more objective comparison
invite interested persons to make the pages of the magazine his 
point of view this issue. After all, as we know - in a dispute 
born truth. Good Luck! 


            *