1996 - year anniversary. Ten years ago,
Spectrum screen first appeared inscription
* TR-DOS Ver ... *
(C) 1986 Technology Research Ltd.
At that time, TR-DOS was one of several
systems (say not the best), which
picked up a cheap home computer one step closer to universal
machine. We also in the country this operating system has
become fundamental. But in recent years have increasingly heard
opinion that the TR-DOS - dead. And we really find the set of
evidence in the form of programs, it is not using the
subroutine TR-DOS. But as they say, "holy place is never
happens. "
DOS is dead. Dazdravstvuet OS!
Offer to meet with the new OSes!
(C) Maxim Gannutin, 1996.
THE CONCEPT OF OPERATING SYSTEM DOMAIN
DOMAIN OS - a multitasking operating
system with a graphical user interface standard
SAA / CUA, as well as full support for file
systems MS-DOS FAT and TR-DOS.
PURPOSE OF CREATION
Originally conceived environment for developing computer
games (strategy and adventyury). The main task was to complete
removal of the application programmer from the hardware.
Programmer must fully concentrate on the game's algorithms,
rather than engage in plotting memory allocation, looking for a
place for the second interrupts, thinking about the ports, etc.
Such issues are relevant to the creators of action games.
This is how the disk subsystem (DSS), system of organization
of residents and a set of graphical procedures. Later, however,
wanted more. Houses began to appear laptop "Windows 3.1",
"MacGuide", and then "Windows 95". For Spectrum
getting hurt: the PC can, but on the Spectrum
impossible? And after a while, there was
Application Program Interface, through which
was implemented cooperative multitasking.
There was an Object Oriented
programming, and graphics from a library of procedures
increased graphics (OGL).
As a result, there was a complete operating
system, with technologies that were not previously implemented
in the Z80.
And, finally, formulate goals:
1. User convenience
2. Ease of programming
3. Transfer of advanced technologies on the Spectrum
Multitasking in OS DOMAIN
As I've said it (multitasking) cooperative. This means that
at the same time computer can be downloaded and run
several programs, but these programs imposed some conditions,
full implementation which ensures bezkonfliktnoe coexist in the
same memory on a single screen and one hook, a few programs.
This is not MagOS, which by definition does not can guarantee
stability.
At the present time, almost every application
program contains a bunch of different components:
character display driver, window system,
Filer, mouse driver, etc. And all this developer spends time
and effort. If you listen to Some programmers, the most often
heard General Discussion is about the above components, rather
than about the meaning of the program. In the PC world has long
been understood that we must do above all, a good windows in
"Winds" or bad - the problem of Microsoft.
Multitasking allows you to not burden the application with
numerous features that are not directly associated with the
primary goal. I wanted to print text from a text editor - the
application sends a message to application "Printer" he and
prints; wanted to get a copy catalog disk on paper - now,
"Filer" sends a message "Printer". Thus,
each application does his own, and only
his work, and the clipboard allows free exchange of information
between applications.
Speaking of filers. The system has a server drag'drop, so the
work in the Filer is as follows. User opens Annex "Filer",
finds the file, she clicks it, the arrow changes to an icon of
file, then the user switches to the application in which he
needs to download the file, and, Finally, squeezing the middle
mouse button (or - Enter). After that went to boot. According
to many, but in reality it is just a few mouse movements.
Disk subsystem (DISK SUB SYSTEM)
In the beginning, DOMAIN OS was targeted only
on the FAT. But the endless conversion with TR-DOS on
MS-DOS tired. I entered the transparent support
TR-DOS. That is, neither the user nor the programmer or the
application does not tell the difference between the discs of
different formats. All information about the files transmitted
in the format of MS-DOS.
PROGRAMMING
Interaction of applications and operating systems dramatically
differs from the traditional model: "cool cycle
calling the operating system, come out of the loop when chtoto
happen. "In the DOMAIN system itself" twists cycle, polling the
peripheral devices, and if For example, the key is pressed,
will cause the active application, as their routine. Such an
organization is quite possible, because up to 90% of cars time
spent waiting for user actions. In most cases, to intensify,
applications spend far less time. Thus, the system can even
between keystrokes, wasting cycles on your needs. Home "motto"
of programming under the domain OS: "We quickly made a deal
and RET".
The system offers a revolutionary technology
programming user interface. You
enough to declare an object (to display
his image and tell the system that, in these coordinates is
such and such an object), and You can forget about it. When a
user tries to do something with the object, the system will
notify the application. A large number of different messages
allows you to organize interfaces of any complexity in a very
short time. I guarantee that all of the API
Windows are easily realized in DOMAIN OS.
Everything I wrote above is really
true, however, when the number of screens
object passes in the third dozen,
there are problems associated with the jumble of codes whose
understanding is extremely difficult. Therefore, there was an
ideology
Object-oriented programming.
It postulates not only a purely formal
rules of the program structure and design
(Something similar to the Hungarian agreement on
C), but also allows you to really simplify
interface design. Another detail: the code is very
easy to change.
PLANS FOR THE NEAR FUTURE
At this time, three groups are working to
software development under the domain OS:
1. Graphic editor "PaintBrush".
2. Text editor.
3. Games' expansion. "
From the Editor SP.
In the next issue of the magazine story about the domain OS
will continue. You will learn about system capabilities and
become familiar with the architecture of the system
applications.
And now - a short glossary to the article.
LIST OF TERMS
SAA (Systems Application Archetecture) - archi
tecture of the system applications.
Application - a program written for Windows (for
For example, written under the TR-DOS program
a TR-DOS application).
CUA (Common User Access) - single point of access, Paul
transducer.
MS-DOS FAT - data storage format of the file,
accepted in MS-DOS.
MagOS - mikrooperatsionnaya system that allows
stored in the memory of the Scorpion few prog
grammes and providing the opportunity to switch
chatsya between them.
Clipboard (clipboard) - System Tray na
myati to exchange data between applications.
Filer - a special application to work with
files, some semblance of boot'a.
Drag'Drop (drag and drop) - a principle used
the employed, for clarity of data transmission.
Click - move the cursor over an object, press and
Release the mouse button.
