About B M E N O T O M Li
In this section you can find chtoto new, share their
achievements.
In the first issue of our magazine for their achievements
in the development ATMTURBO you share our chief technician.
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(C) BREEDERS CONSTANTINE
PC screen (ATM-) TURBO 2 +
Today we talk about screens, realezovannyh PC (ATM-) TURBO
2 + (hereinafter TURBO 2). Someone might say, they say, why all
this lovers SPECCY, because these screens out
beyond the simple SPECTRUMa. It is difficult not
agree. But since there are some computers, you can not forget
about their capabilities, and they are based on good old
SPECCY. In addition, readers ZX-REVIEW probably noticed in a
magazine for 1995, article about the next development
for SPECCY in graphics - graphics processor with great
potential. So while SPECCY alive, to him will be
invent all sorts of devices, and we'll tell you about their
work.
And so, TURBO 2 to implement four
main screen:
1) high color screen resolution
2) high-resolution screen
3) SPECTRUM-screen
4) the text screen.
The first - the screen high-resolution color 320h200
points, each point of its tsveta.Odnovremenno on the screen may
be 16 colors from a palette of 64
color (similar to EGA).
It takes about
32 KB, and having
is a 2-straitsah RAM: the first
fifth. Each
page is divided into
and the two halves
ie gain 4
memory area in
are stored
dannye.Tak as
one point is given 4 bits, one byte
contains information on two points. The zero point (which is on
the left) correspond to 0,1,2 and 6 bits, and for the first 3,
4, 5 and 7.
Now revisit the four areas of the screen. For a more
intuitive explanation, we consider, for example, the horizontal
line N-finite length, drawn from the origin (upper left).
The first two points of the lines belong to
zero-half of the first page of RAM.
The following points - half of the fifth zero
page. The fourth and fifth points lie in
first half of the first page, and the sixth
and seventh in the same half, but the fifth
stranitsy.Ocherednaya pair of points will again be
belong to the zero-half of the first countries
boundary, but with the address of a large unit (address see
Fig.). Ie if the 1-th page is located at the address # 0000 and
by 5 to # 4000, then the 0-I 1-I will point at # 0000, 2 nd and
3 rd at # 4000, 4-I and 5-I # 2000, 6 th and 7 th in the #
6000, points 8 th and 9 th at address # 0001, etc.
We now turn to the second screen.
Its size is 640x200 tochek.Pamyati
it is the same as the screen and 320h200 and
pages are divided popolam.No here
is another organization of the screen. Now the fifth page is
only responsible for pixels, and the first
for the color, ie, atribty (almost like
in the screen SPECTRUMa). Here the color
given for one znakoryada,
ie to 8x1 pixels. Four
bits specify the color
INK (included
points): zero
1 st, 2 nd and 6 th.
The remaining bits
sets the color PAPER (Disabling a).
Sixth and seventh bits can be, although not
quite right, call the bits of brightness. C
number of colors the situation is the same as that
in the screen 320h200: the same 16 colors from a palette of 64
colors. Now for the halves of the screen. In the zero-half are
even columns (0,2,4 ,..), and in the first, respectively, the
odd (1,3 ,..). This applies to attributes, and to the pixels.
SPECTRUMekran will not be considered because
his organization
known to all, and
Who does not know
advise you to read
Books INFORKOMA
SPECTRUMa on schedule.
That's still the text
ekran.On almost repeats
Screen 640x200
tochek.Tolko attributes now set the color for one
familiarity, in the fifth page, instead of data
of pixels are the character codes. Decoder of the screen
contains 256 characters, and "stitched" into the ROM RF-2, so
that if someone type in this mode of
soul, it can "alter". Benefits
the screen before the previous is that
He takes little memory (less than 4 KB), and
easy to work with texts, ie it does not
should turn up the routine, at 80h25 the amount of characters
(and read the text in the This screen is much better than a
similar print on the screen SPECTRUMa because not implemented
by software).
In conclusion, I want to say that, as
SPECTRUMe in here every screen two.
They switched the third bit of the port
# 7FFD, while page 5 and 1 are replaced by 7 and 3 pages.
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P.S.
Talking about screens TURBO 2 is not
over as there are four
Hidden screen.