IRON MADE IN
(C) Alone Coder / Invaders 8
Pentagon 1024
The first time I write to the editor:). Want to assist
good paper, and then hurt a lot has bred bad. Since
nothing to write about, talk about some of the mysteries of
computers and something any handheld device. Schemes will be
avoided, as the reader, they frighten, but to draw them broke.
To the surprise of many in the world there is such a
machine, as Pentagon 1024. What distinguishes it from other
clones ZX Spectrum and why is there so little news? Just this
computer is nowhere produced. Each instance of it is collected
by hand, mostly based on Pentagon 128. Naturally, this state of
affairs does not There is no single complete computer admiration
worthy that in general has developed a standard. Want
to remember the good word of friends, without whom this would
standard (and the computer, too) was not: VMG, Ivan Mak, Mr.Gluk
'Co. and others I do not know.
Resource Management 1024 Pentagon is using the port
# Eff7 (decoding minimum of A3, A12, IOWR, on reset RES):
bit 0 - "attribute to the byte" (a4b) - hardware multicolor,
attributes to address # 6000. 1 - enabled.
bit 1 - 512x192. See Deja Vu # 6. 1 - enabled.
bit 2 - latch memory above 128k. 0 - there is a memory, 1 -
no.
bit 3 - Not used. I suggest: read only cache. 0 - can
record, 1 - can not.
bit 4 - GigaScreen (hardware overlay the 0-th and 1 st
screens. Interlaced: C35 = (bit4 '8kHz) xor C35.) Not used.
More precisely, in the game "Homer Simpson In Russia" instead
of port # eff7 spelled # fffc.
bit 5, 6 - reserved for Rom-Disk. Since this thing is not
rasprostranenaredlagayu: bit 5 - the inclusion of Sound Blaster
(sm.ZXGuide 2) it 6 - inclusion of 384x304 (ibid.).
bit 7 - Gluk CMOS (real time clock). Sm.shemu at Deja Vu
# 8 (pravdaam instead # eff7 also written # fffc). 1 - CMOS
ports active.
In what order capture device A13V and C35?
A13V - 13th address in the circuit switched video controller
(for ex. Pentagon first version 11/D17), which was originally
the land.
I have collected since: a4b forms, SB folds, 512x192
commutes, 384x304 switch. If you collect at 384x304
multiplexer (KP11, KP12 possible), then: on # eff7 bit 6 must
switched old A13V (if bit 6 = unit) or land
(If bit 6 = zero), and the received signal must be admixed (OR)
to C35. Then, during a bit 1 it will be 768x304,
heh heh ...
C35 - 1-st bit rates page in the circuit switching
video controller (on Pentagon 13/D17), originally # 7ffd bit 3.
I have not caught, but, logically, first
768x304 commutes and mixes, and then GIGASCREEN CORF. On
384x304 then be possible X-Color'y with reduced flicker.
ROM
TR-DOS v5.13Fm - conventional TR-DOSmeetsya accelerated
positioning (because of which, unfortunately, buggy Monster
Commander); drive D - RAM-disk, we can rewrite it
program yuzayuschuyu # 3d13, and rulitsya with high speed ...
Gluk Reset Service v5.3K - operating system;)
stitched into an unused page 27512 (usually zero).
The computer must be in the back of RESET.
Reset hot buttons: RESET / 1 - quit to STS, RESET / Space
- TR-DOS. It is useful to return to the ALASM or STS, when
debugging program hangs.
It is possible to see screens of the interrupted program and
writing them to disk (described version, however, suffers from
glitches with respect to the 0-th screen). Present sohranyalka
and vosstanovilka directory on the disc 161-th track. There
vstoroenny boot + Perfect Commander 1.52. Author - Renat
Mammadov 2:5026 / 5.46 @ fidonet
Cache (cache) 32k
Chip static RAM, put the scheme in LPrint III
addresses # 0000 - # 3fff. Typically used bourgeois 11C256. In
Turbo mode program in this memory area is not subject to
WAIT'am.
IN (251) - enable the cache, IN (123) - off. Senior address
switched signal DOSEN (15 th address ROM).
Some programs that use the General Soundonfliktuyut with
LPrint III. Advise the authors of these programs first identify
the presence of this device (and it is common, however), and
then check GS.
Mouse (Kempston mouse)
Two-or three-button mouse on the ports (# fbdf) =
coordinate X, (# FfDF) = coordinate Y (considered from the
bottom up!), (# Fadf) = button (Zero - the button is pressed,
the unit - released). Standard button layout (the CREATE SOFT,
and left the scheme devised Mesons): left button = D0, the
right button = D1, middle button = D2. Wiring diagram and
directions for the conversion of mice published in ZX Format #
5.
How to determine whether the mouse?
The mouse is attached to the computer, if the data bus
it is stable, and the values read from all 3 ports of the
mouse, not equal. Program-opredelyalka, the probability of
failure 1 / 65536:
HALT
IN A-1)
CP -1
JR NZnet mouse>
LD BCFADF
IN CC); (# fadf) = button
IN A # DF); (# ffdf) = Y
CP C
JR NZest mouse>
LD AFB
IN A # DF); (# fbdf) = X
CP C
JR NZest mouse>
<No mouse> ....
Other Devices
Standard accessories basically sound:
AY (of coz), COVOX (necessarily), SounDrive v1.51 (emulation
COVOX, sm.shemu in the annex to the Deja Vu # 1). Theoretically
proved connectivity General Sound. It seems that DMA
UltraSound should also work, but there is no data on this;).
Standard Modem - Hayes scheme Kondratiev (sm.Oberon # 4)
at 14400-57600 baud.
Disk interface Beta Disk + TR-DOS, 55 "and 3" flops. By
Concerning the second is nothing good I can not tell from the
first recommend Robotron, in the worst case Teac (because of its
retardation and short life span), and the best drives,
I watched - Mitsumi to 1M.
Standard interface hard drive yet. In fact, not
so important, would be compatible screw with old applications.
After all, if necessary, the user can always
copy a disk image to a real floppy disk and load from there.
On the Amiga, for example, does just that. It would be nice to
compose simple scheme and Commander / Viewer under it.
How to programmatically distinguish Pentagon Pentagon 512
of 1024?
Standard port memory expansion in the Pentagon - # 7ffd.
Determine the actual amount of memory on that port, not
including the 48-th mode in case of 512k, it would be
impossible if not for the next subtlety.
Latch 48k/non 48k (# 7ffd bit 5) is triggered only
when the memory above 128k is off, that is
when the 2-nd bit port # eff7 set (switching this bit
controls, among other things, OSes Gluk Reset Service).
Therefore, if the computer responds to the reversal of this bit,
it is possible to lose bits and quietly checked the memory.
Just in case the extra bits port # 7ffd (6)
connected in parallel port bits # dffd (0) to
maintain compatibility with the software, wrote under the Profi
1024. But should bear in mind that the work of a single port #
7ffd occurs faster.
Why do some programs conflict with the port # 7ffd?
In such programs to quickly switch pages
memory is used part time addressing port (# fd), but
filling the same pages (load, for example) is carried out at
using the full address. As usual, with an incomplete address
set 6-th bit of (shtop worked for Scorpio), in
resulting in the first and second stage, we have not
corresponding to each other activated by number of pages.
Owners Pentagon 512-1024 accounted for time
such programs off the top pamyat.Izbezhat you can:
if in one place in your program uses an incomplete
adresatsiyao use it throughout the program!
Sensible suggestion
Propose to use the port # eff7 read. From
unconnected bits (which is not implemented corresponding to this
bit device) should be read by a unit attached to
return values recorded in the port. Pick it up easily,
but all the additional devices will be easy to program
determine. And if the port # eff7 to read is not implemented (ie
If the port # eff7 read a constant value), then we can
provide the program to select a configuration
manually (as it was until now).
Alone Coder / Invaders 8 beat his fists on the AC Edit v0.43
