Correct video output
ZXNet echo conference «hardware.zx»
Hello, CheburatoR
Che> While developing my clone (from Leningrad1) Spectrum I encountered a problem
Che> video signal, namely, I tried two PAL encoder chips tda8501 and
Che> ad724 came to the conclusion that something is wrong :mad: well, how about it - the video was made
Che> through... in short, non-compliance with the PAL standard, the problem was solved by using
Che> 64Kb rom chip, flashing the correct signal diagrams, and lo and behold
Che> everything is now perfect - PC tv card on bt878 which even did not understand
Che> now shows frame synchronization as it should :smile: attaching
Che> diagram (for an idea of the correct signals) and how it looks on
Che> PS monitor. If there is any interest, I can give you a revision plan
Well, no wonder!
Of the clones, in my opinion, KAI and ATM more or less meet the standard,
the rest are a complete anus, especially at the Pentagon.
Hello, All
While developing my clone (from Leningrad1) Spectrum I encountered a video problem
signal, namely, I tried two PAL encoder chips tda8501 and ad724
I came to the conclusion that something was wrong :mad: well, how about it - the video was made through...
in short, non-compliance with the PAL standard, the problem was solved by using a rom chip
64Kb, with the correct signal diagrams flashed, and lo and behold, everything is now perfect -
PC TV card on bt878 which did not even understand frame synchronization now
shows how it should be :smile: I’m attaching a diagram (to give an idea of
correct signals) and how it looks on the monitor
PS. If there is interest, I can give you a revision plan
File: Resize of PA141760.JPG http://zx.pk.ru/attachment.php?attachmentid=1810
File: Resize of PA141762_.jpg http://zx.pk.ru/attachment.php?attachmentid=1811
File: video diagram.jpg http://zx.pk.ru/attachment.php?attachmentid=1812
Hello, CHRV
Che> PS. If there is any interest, I can give you a revision plan
To the studio!
And by the way, how did you get the third picture? Where did the correct diagrams come from?
signals conforming to the PAL standard? (I could only find NTSC so far)
The keyboard has been coolly redesigned!!! It looked like it was made of film (???),
exactly how it was remade??? (I want to look at the photo from the back side).
Hello fan
fan> how did you get the third picture?
fan>
screenshot from my program with which I made the firmware
fan> Where did the correct signal diagrams that comply with the standard come from
fan> PAL ? (I could only find NTSC so far)
fan>
http://www.kolumbus.fi/pami1/video/pal_ntsc.html
fan> Cool redesigned keyboard!!! It looked like it was made of film (???),
fan> exactly how it was redone???
fan>
I was specifically looking for a keyboard with rubber buttons, with a film one - this is the approach
unsuitable. the principle is simple - 8x5 matrix +19 additional buttons, like keys
I used bu4066 chips (I had them on hand)
about modification - you need one microcircuit like 27C512 (better with less time
access, I have 70ns) into which the attached rom.bin file is flashed,
should work for Leningad1 and similar clones, numbering of legs for the body
PLCC32
according to the Leningrad1 scheme:
BORDER instead of D13-6
SYNC instead of D11-6
BLANK instead of D36-15
in principle, you can also attach an INT signal until you change it
as a result of the rework, several logical elements are freed
File: PA141778.jpg http://zx.pk.ru/attachment.php?attachmentid=1813
File: dorabotka.jpg http://zx.pk.ru/attachment.php?attachmentid=1814File: rom.rar http://zx.pk.ru/attachment.php?attachmentid=1815
Hello, CheburatoR
I wonder if anyone else besides me has done this subject? I agree, int and border
work correctly (but the signal from the border must be sent exclusively to
KP13), but the screen is shifted VERY much to the right, even more than on
the "original" Leningrad-1 (which, in fact, I remade), and if on
In the “normal” scheme the screen is simply shifted, but with this ROM the left is black
vertical stripe. Tested on Samsung LCD via Scart-RGB. On Samsung with
There is no CRT row synchronization at all. :(
Gentlemen, can anyone give me some advice about shifting the entire screen to the left? Maybe
What was floating around the forum earlier, but I can’t find it? I really don’t want everything
screw it into the ass and remove the ROM. Respect to everyone in advance.
Hello, CheburatoR
By the way, my project is slowly but progressing :), I recently finished the “video”
board", H0..H7, V0..V7, ROM for int, blank, sync and PAL are generated on the board
encoder, now I’m installing a “cpu board” - like mainboard, then it’s planned
generalsaound, flash card with USB
File: zx_video_board.jpg http://zx.pk.ru/attachment.php?attachmentid=2570
Hello rw6hrm
rw6> Gentlemen, who can tell me something about shifting the entire screen
rw6> to the left?
Most likely the problem is in the line frequency, it should be 15.625 khz, counters H0..H7
should change from 0..255, and on the border from 64 to 255, it turns out 7Mhz/448=15.625
Khz, in the diagram it’s how it’s done for me
File: h0-h7.jpg http://zx.pk.ru/attachment.php?attachmentid=2569
Hello, CheburatoR
Beautiful, you can't say anything... compared to my tangle of wires :) Yes, also -
(most likely this is due to the high-speed ROM, I have 45ms access, also Vinbond, but
deepovsky) on a piper through each half of the familiarity thin vertical
line - where to throw the conder to tighten up the rear?
Hello, CheburatoR
So, in comparison with my diagram (like the one posted on SBlive.narod.ru) I found
differences in D4 with 1 and 10 legs. ...damn, I didn’t even think about it, the first original
has been lying around since 1989, the screen in it was also completely moved, now in
remake created the same trick... By the way, if anyone still has real under
nickname "Vesta IK-30" produced by the Stavropol "Signal", then it contains the same
shift, most likely for the same reason...
Hello rw6hrm
I also did the same at first according to the Leningrad scheme, then I redid it, but 100%
I’m not sure that this is a mistake in the Leningrad scheme (is everything really so secretive in the original
:confused: ), regarding the black dots - try soldering about 15-60 pf
between blank and ground
By the way, the position of the screen can also be changed by firmware, left to right up and
down, also the duration and location of the signals, using the blank signal
For example, you can make an original black light inscription on the border :)
Hello, CheburatoR
Che> by the way, my project is slowly but progressing, I just finished it
Che> "video board"
Cool :) Is this done for a specific case?
Hello fan
fan> Cool Is this done for a specific case?
yes, under the old building in which my second Leningrad was located1
kgb> Share your experience, how do you make boards? Very beautiful for an iron
kgb> turns out. Or an iron?
Generally speaking, I don’t really like the technology, but for me it’s more interesting to do it
doing it yourself, it’s still more expensive in terms of money and time than ordering
Hello, CheburatoR
Che> I recently finished the "video board"..., now I'm building the "cpu board"
Share your experience, how do you make boards? It turns out very nicely for an iron. Or
iron?
Hello, CheburatoR
Che> generally an iron, I don’t really like the technology but it’s more interesting for me
Che> to do it yourself, it’s still more expensive in terms of money and time than
Che> order
As I understand it, you lay out the board in EDA - print it on a laser - etch it - drill it
- you solder..
1. What size is the pad in the EDA (yours are round)?
2. What size is the hole in the EDA?
3. Can't you metallize the holes?
4. How wide is the track in EDA?
5. Is the track covering Rose alloy?
6. How do you combine the top and bottom patterns when heating with an iron?
It didn't turn out too bad for me either. True, single-sided boards and from a ready-made BMP
file. I tried to make a double-sided one, but it turned out to be a displacement of the top and bottom
sides with all the consequences.....
Hello, CheburatoR
Che> generally with an iron
What do you print on, very interesting? I mean on what paper?
Hello, kgbplus
And I’m also interested in what specific paper and printer. Lately
It doesn’t work for me... apparently the printers are strange, very economical...
Hello andreil
and> And what microcircuits are used in your circuit, maybe I’ll order a board.
1. domestic microcircuits, except 64kb ROM from winbond in PLCC32 package, and fell
ad724 encoder from Analog Devices
2. I do not accept custom fees
3. what will you do with it? it connects exclusively to the "ZX128 CPU
board", everything I do is for myself, I make it from what I have lying around
at home and not based on cheap mass production
PS it is not yet known whether this board works at all :D
When I make the CPU Board and fix all the glitches then I’ll post the diagrams and wiring if
someone will ask
Hello fan
fan> And I’m also interested in what specific paper and printer. Last
fan> I'm running out of time... apparently the printers are weird
fan> very economical...
kgb> What do you print on, very interesting? I mean, on what paper?
I tried it on different LaserJets without an economy mode, the paper was glossy
thin from magazines, the white part is better, but it can be printed, just not on
pictures..... printed things are washed out worse. If possible to buy
thin coated paper, then this is the most haymaking!
In the attachment what I got...
File: DSC01158_resize.JPG http://zx.pk.ru/attachment.php?attachmentid=2578
Hello, kgbplus
kgb> Well, it's just beautiful. If it’s not difficult, describe your technology in detail.
To avoid flaming here, I’ll create a thread in “Flame”
http://zx.pk.ru/showthread.php?p=38573#post38573
Hello, do_se
do_> In the attachment, what worked for me...
Well, just beauty. If it’s not difficult, describe your technology in detail.
Hello, do_se
And what microcircuits are used in your circuit, maybe I’ll order a board.
Hello andreil
I re-soldered the counter as suggested - everything moved wildly to the left :( and the inscriptions
began to flicker. I don’t even understand anything, Cheburator, plz, make a personal comment
operating principles of D3 and D4, as well as the algorithm for generating horizontal pulses
in your ROM. Thank you in advance
By the way, Conder on the border does not save you from vertical stripes...