Iron - a complete guide to setting up Pentagon-2.

                                          
Dr.DRAGON/AREAsoft/SIBERIAN ALIANCE       
------------------------------------------
                                          
 Hi all Speccy World!           
                                          
   I was inspired to write this article.
pushed by the debugging situation PROFI 512Ky
DIAMONDa.  In the computer documentation, there was
very little useful information (if you compare
thread complexity PROFI and PENTAGONa with their ru-
troubleshooting guides and descriptions
working nodes, it becomes funny :(. We
I had to turn my guts over until
I managed to understand the circuit a little. When
anyway, when I assembled my first
PENTAGON,with my setup guide,
It took me a total of
complexity of time no more than a week, accepted
May I take into account that I was in hardware then
practically a lamer (could onlycarefully
solder).                                   
    A joint with dots on the screen, like later
It turned out it was only because of the power supply,
but I couldn’t believe it for a very long time.   
    I raised this question because...
everyone who has a useful VERIFIED
EXPERIENCE information about eliminating glitches and
o improvements to hardware, they wrote about this income-
thorough and detailed articles from cxemkamu and
placed them in all kinds of electronic devices
Denmark. So that any user can correct their
computer independently and without spending money.
Then maybe it will be possible if we don’t attract new ones
users to the platform SPECCY,  then at least
keep those who can abandon their
computer, because of the endless torment with it. Xo-
you sometimes get rid of seemingly henon-
pabumoro glitch, it can be very simple
(learned from the example of my computer). Call back
Hey, iron connoisseurs! And those who need
ma help, let them write their questions to the newspaper
dew.                                     
                                          
------------------------------------------
                                          
   During useSPECCY we sometimeswe discover some glitches, and before
The question arises:"How to get rid of them?".
At the same time, we are still wondering how it would be
get everything done at no extra cost. And special
costs are divided into two categories:     
                                          
   1. Personal free time.             
                                          
   2. Personal free money.            
                                          
Your PATH in achieving normal work
Everyone chooses a computer for themselves:  
                                          
   1. If you want, you can take your own
the one who does this should pay
his hard-earned money (which he could
pocto go for beer) and after a while
time to get your car back, maybe
but, along with the same glitches, maybe
even with new ones.                          
                                          
   2. If you want, you can borrow y
someone an oscilloscope and a soldering iron, buy
half the beer money saved, and
do the setup yourself.Any adjustment begins with a check
power supply unit (PSU).  It's best to take y
someone a powerful power supply with which he
the computer plows well with the maximum amount
quality of all kinds of accessories (disk drives,
mouse, GS, etc.). Connect the power supply to yours
computer and see how the whole system works
ma In my case, all the co-
anything, although before that I considered my self-
efficient power supply on KPEHkax is quite powerful, and
blamed it all on the retarded memory she had
is not. And these jambs were expressed like this: 
   My computer (PENTAGON 2+) calmly
worked until I forced it to work
push towards the disk. Things have already started to happen here.
to create miracles.  The computer could boot normally
terribly, it could just freeze, or it could
let freeformat! Especially unloved y
it was IS-DOS and HONEY COMANDER,
I failed to let it in 100% of the time.  
   If everything went well, then you need
purchase a new power supply (or not give it to
rented ass :)).                  
   If, after all, manipulations with the power supply are not pro-
rolled, then you'll have to get into the gut-
ki to your "dinosaur", or go along the path
No.1 (see above) and do not read this nonsense until
end . If you still choosesecond way,
then read on.                          
   I describe here PENTAGON 2+,but when
If you wish, you can find analogies with other
clones SPECCY.                           
                                          
   First of all, don’t rush to give back the power supply (with
it will give you a better chance of success).
Secondly, find an oscilloscope somewhere,
It's best to have a two-way one.  And thirdly -
take a low-power soldering iron.  If you don't
If you know how to work with a soldering iron, then it’s better to use
children also call someone who knows how to win
give him a beer :)                           
   Well, we've already done the most important thing,
now you need to calm down and try
to delve into the scheme, for this you will
you just need a bottle of beer (for this
rationalization proposal there is a patent in my name :)  
                                          
   Below is the text of the printout "PYKO-
BOARD ON SETTING UP A PENTAGON-2 COMPUTER,
SINCLAIR 128 Kb." in my edition.        
                                          
                                          
 Debugging a computer.              
During debugging at any point on the board
you may encounter three standard si-
situations, so you need to know the methods
detecting these errors:                  
                                          
   1. CLOSURE.                          
 Typically difficult to detect
signals that are poorly synchronized on the oscillator
lographe.  But you can guess by following
that such a signal is usually 3 levels-
Nya, the third level somewhere2.5Vappears,
when the signal at one output is 5V,and at the other -
gom0V (average value).                
                                          
   2.BREAK.                              
 Not always easy to detect if
signals are static. Since all logic is
board - TTL, then if at the input we have
row 2V, therefore the signal does not reach the place
it comes.3. THE MICROCIRCUIT IS FALSE.              
 It happens that a short circuit or break is found
are located inside the MS, then the main method
struggle is to cut off the exits of this MS (beam-
see the paths leading from them :) and check
signal (see 1 and 2). Or cut off the inputs
MS, if they are locked into something. Harder with
fight this if there is a lot of feedback and
the cutoff of the output greatly affects the inputs of this
same MS.                                    
                                          
   After you have taken your computer out of
box and laid out its intestines on the table, maybe
but start debugging it. And we need to start
from the fact that:                              
                                          
   1. Remove the Z80, firmware from the panels
27512, firmware RF2 or RFS, VG93;        
  2. Connect power 5V (12V until debugging
there is no need to connect the drive).After connecting the 5V power supply
on the monitor (TV) screen should be
a "chessboard" will appear. If this is not the case
happened, then we need to start debugging
synchronization and display logic.   
   At the MS output DD1:4 check for presence
frequency 1HMGts.If you have a different computer, then
you need to find something like this in the diagram: 
                                          
      ┌---┐ ┌---┐                    
   ┌--┤ ├---┬--┤ ├---┐                
 │ └---┘ │ └---┘ │                
   │ ┌------┐ │ ┌------┐ │                
   │ │ DD1.1│ │ │ DD1.2│ │                
   │1│ │2│3│ │4│                
   ├-┤ o-┴-┤ o-┼---o 1HMHZ      
 │ │ │ │ │ │                
   │ │ │ │ │ │                
   │ └------┘ └------┘ │                
   │ ┌-┐ │                
   │ │ │ Q1 │                
   └--------┤│ │├--------┘                
             │ │                          
             └-┘                          
                                          
If there is no frequency, then 3 situations are possible:1. Quartz is faulty (such a metal
kaya or glass figurine on the board);    
                                          
   2. Microphone is faulty (such a direct
solid plastic or ceramic bead
choke with many legs :));                
                                          
   3. Short circuit or break between tracks
(such metal strips, unknown
on which they are glued to a sheet of textolite);
                                          
   If the frequency 1HMGZ is, then you need to
see if there is a line and a frame
synchronization  Lowercase cuhxpa fits
DDb:1, signal duration bChmks.If
there is no frequency, then check all the logic above
this MS, following from DDb:1 to quartz. Check
Check whether the signals GND (ground) and
+5V  (+2.5V under resistors) on free
MS's legs. On DD6:2 suitable frame hour-
that duration is 2Omc. If it is not there, then
similarly we follow from this leg to the counter-
camDD11, DD12.If both frequencies are present,
to check whether their mixture reaches the mono-
tora.  To do this, you need to checkDD72:11,
if there is a SINC  signal, then there should be
raster if the screen is blank (black or white)
ly) i.e.  there is no frame, then check RGB on
MS DD72:3(6,8),if RGB no, then check
multiplexers DDChb, DDCh7.Check yes
are there signals at the outputs, if not, then on
inputs (14H, 2H), and whether the signals reach
ly with DDХО, DDЧ2.If any signals are from
exist, then check 14H for everyone
PYS(RU7)  and whether they reach DDХО-DDЧ2.
If at the outputs DDХО, DDЧ1 there are nosignals, check all clock inputs
DDХО, DDЧ1, DDЧ2 (11Н, 1Н). As a rule
after the appearance of the above signals,
catch, a frame appears, but nevertheless
It is recommended to check whether any
more signals to all MS inputs DD16-DD19,
after that - to all MS inputs DD20-DDЗ5
(PYS  or RU7). After this you can npucty-
proceed to the next step.                  
   Use the correct key to insert the processor
Z80. Alternating
There are stripes of black and white-blue-white colors
that, i.e.  the first 8 dots are black, then 3
white, 3 blue and 2 white, etc. When pressing
tii on RESET  these bands can change
in some places. If this is not on the screen, then you need to
check if the legs are closed Z80; yes
there are signals at 4H and 5H RU5 (RU7).          
                                          
 ┌---------------------------------------┐ 
 │ Possible errors in computer operation │ 
 │ and their correction│ 
 └---------------------------------------┘ 
                                          
   1. THE KEYBOARD DOES NOT WORK.             
                                          
Check whether there are signals at the output DD70.
If there are no signals, and the remaining signals
pass, then MSDD70 does not work. Analo-
It is convenient to check DDHH, for this
may have to be cut off from the data bus
some exits.                         
                                          
   2. BO ENTIRE SCREEN VERTICAL BLACK
STRIPES BO THE SECOND HALF OF THE PLACE.     
                                          
Does not work or there is a break in MS DDЧ1.          
                                          
   3. WITHOUT ROM AND Z80 THE WHOLE SCREEN IS WHITE.     
                                          
Incorrect/RAS or /CAS on ryshkax.    
                                          
   4. WITHOUT ROM AND Z80 THE WHOLE SCREEN IS BLACK.    
                                          
Does not work or is broken DDb:11, DDЧ2, DDЗ8.
Possibly incorrect/RAS and /CAS.        
                                          
   5.  WHEN RESET, CONSTANT OUTPUT B 48K,
FREQUENT FLASHES.                         
                                          
Check node  DDb1-DDb5. Perhaps this
occurs due to slow memory (more
two points on the body).                   
                                          
   6.  WHEN ROM IS INSERTED, LONGITUDINAL BLACK-
BLUE AND BLUE-WHITE-BLUE STRIPES.            
                                          
Check the signals at 20H and 22H MSDDZb.   
                                          
   7. WHEN ROM IS INSERTED THERE IS NO OUTPUT B ME-
Nude.                                       
                                          
   Check signals for 1H, 20H, 22H and 27H
MS DDZb. Check whether these signals are reaching
before all other MCs.                     
                                          
   8. THE COLOR OF THE CURB AND THE TONE OF THE SOUND DO NOT CHANGE -
CA.                                       
                                          
Check if there is a signal on DDЧЗ:9  and
DD10:3.  If there is a signal, are there any
signals at the outputs of these MSs (when the background changes
or sound).  If not, replace
MSy, otherwise there is an open circuit.     
                                          
   9.  PRINTER DOES NOT WORK (only for
PENTAGON 2+).                             
                                          
 1)  Make sure that  ENPR when connecting
the printer is grounded;                     
2)  Ground  DDb2:2, enter commands
LPRINT and LLIST (after dialing any
fight text in BASICe), then check there
Are there signals at 20H and 18HDDZCH, DDSS:11,
DDb7:6. If there are no signals, then go along the
kidney, figuring out where the signal is not reaching,
check if there are signals immediately after
input LLIST.                              
                                          
  10. ON THE SCREEN, TIME FROM TIME APPEAR-
XI POINTS.                                 
                                          
Adjust power supply (for PENTAGON
you need5.5V)or select capacitanceC16.    
                                          
  11. READING WITH MAGNETO DOES NOT WORK
ON.                                       
                                          
 1)  If there are synchronization signals (motion
upward or downward horizontalred stripes, then adjust the head to
tape recorder, you may have to amplify in
MF linear output, removing resistance to
exit MF.                                
 2) The screen blinks like a border, but there are no stripes
gives.  Check how the signal 300mB is amplified
is MS DD100 and whether it reaches DDHH:4.  
                                          
 12. DARK SCREEN WHEN SET THE CURB IN-
BEERS BACKGROUND INSIDE THE FRAME.                 
                                          
No quenching. Check 18H and 1H DDCh7, DDChb.
                                          
 13. THE SCREEN IS ENTIRELY GRAY WHEN SET A CURB
THE ENTIRE SCREEN BECOME THE SAME COLOR.    
                                          
No frame signal at 2HDDCh7, DDChb.2H
DDChb, DDCh7  must be connected to
DD10:8.                                   
                                          
  14. THE DISK DRIVE DOES NOT WORK.               
                                          
 1) Check all power buses, including
leVG93:40N (db. 12V)                    
 2) Using the keysCAPS SHIFT and the cursor
select BASIC 48,type the command in it
PRINT USR 15616.If there is no output to the screensaver
ku TR-DOS,then check whether it switches
trigger DD76and are there any signals at the output
in TR-DOS on DDZb:1.  If there are signals,
try to increase the capacityC3,possibly
you will need to connect a capacity 200pF to
DD76:10.                                  
 3)  In the splash screen  TR-DOS. Enter the command
LIST. If the inscription  *ERROR*, then it is possible
the disk is unformatted, then format it -
titrate. If the message No disk (with closed
window and correctly inserted dis-
com), then check whether the pe-
straps (dips) for selecting the device number on
drive board. Check if there are signals
on 26N, 27N, 35NVG93,if there are signals,
then increase C1 to 500pF.                 
                                          
  15. DISKETTES ARE POORLY READABLE.             
                                          
Enlarge a littleC2.Maybe it doesn't work
pre-compensation.  Check logic operation
DD97  and downstream (signals Q15, Q16,
Q17).                                     
                                          
  16. THE DISK DRIVE DOES NOT WRITE OR FORMAT
DISKS ROLL.                               
                                          
Check whether all signals reach DD96 and
DD94:2. In case of unformatting, it is possible
and poor reading (see paragraph 14.3).             
                                          
   ┌---------------------------------┐    
   │ Description of individual blocks of the circuit │    
   └---------------------------------┘    
                                          
DD1-DD14  form the horizontal frequency (signal
nal C4),frame rate (DDS:8),signal
frames (C5),blanking(BL),frequency noctyna-
that form on DD16, DD17,
screen image res.                  
                                          
DD18,DD19 multiplex addresses from pro-
processor with the selected page.            
                                          
DD15, DDЧ9-DDS1  form control signals
niya and memory access.                   
                                          
DDb1-DDbCH set the page number (DDb2:2Н,
5Н, 7Н), 2 screens (signal C36), latch
for 48K mode(DDb2:15).                 
                                          
DDЗ9 reads data from the handles.  
                                          
DDЗ8,DDЧ1,DDЧ2 encode 8 points in one
familiar.                               
                                          
DDЗ7,DDЧO encode the color of black and white
check, their brightness and the bit of familiarity blinking. 
                                          
DDЧЗ,DD10:1 set the border color (K9, K10,
K11),output to tape recorder(DDCHZ:15), sound
(DD10:5)                                  
                                          
DDBlack, DDCH7switch the colors of black and white
points, as well as curb and blanking.          
                                          
DD72 buffer for connecting a monitor.      
                                          
DD92,DD93 form a PLL for data with a
driver                                   
                                          
DD96 signals for writing to the disk drive.          
                                          
DD100 converts an analog signal from a
MF linear output to digital.             
                                          
DD70,DDHH generate signals from the keyboard and
MF.                                       
                                          
DDЧ5 generates signals /RAS and /CAS for rus-
shek                                      
                                          
DDS2,DD5Ч,DDSS,DDbb,DDb7 generate signals
printer, when connecting the printer, you must
it is possible that the signalENPRin this connector (the
cut connector) was grounded, otherwise the printer would work
won't bother.  If ENPR is grounded to
board, then be prepared for the fact that some
Some games will not run at 48K. For ini-
printer centralization - command LPRINT, yes-
then any commands (LLIST, LPRINT, COPY);
line translation with command LPRINT CHR$ (3),
to exit to the printer menu - LPRINT CHR$
(0);CHR$ (0).                             
                                          
DD88  generates control signals for
drive: select recording density
(DD88:2); loading magnetic head
(DD88:7); /RESET (DD88:10);selectdisk-
yes (DD88:12Н, 15Н) together with DD98       
                                          
board, then be prepared for the fact that some
Some games will not run at 48K. For ini-
printer centralization - command LPRINT, yes-
then any commands (LLIST, LPRINT, COPY);
line translation with command LPRINT CHR$ (3),
to exit to the printer menu - LPRINT CHR$
(0);CHR$ (0).                             
                                          
DD88  generates control signals for
drive: select recording density
(DD88:2); loading magnetic head
(DD88:7); /RESET (DD88:10); select disk
yes (DD88:12Н, 15Н) together with DD98       
                                          
DD89  selects the deviceor MSyDD88,
DD91, VG93.                               
                                          
DD75-DD77,DD82-DD85 switching signal
TR-DOS ROM and access to control registers
disk drive.