Author Topic: Vintage chip Programmer : " Micropross ROM 3000U "  (Read 18477 times)

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Offline VinceTopic starter

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #50 on: November 07, 2022, 08:19:17 pm »
Yes it was my fault I admit.... I saw "board", I saw "similar price to the ad PCprogrammer showed me on aliexpress"... so... CLiCK CLICK CLICK !  :-//

I should know Ebay sellers better than that !  :-DD
 
PCProgrammer, yes of course I can return it ! We are in Europe, law makes it so that anything you buy remotely, ie that includes internet, you can return within 2 weeks no questions asked !
It's the law.  Sometimes law are cool !  8)

Thanks for the link to the ACTUAL board, will order that !  :-DD
 

Offline VinceTopic starter

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #51 on: November 08, 2022, 04:31:14 pm »
Item has just been returned... waiting for the process to be completed and my money refunded, before I commit to ordering the actual board, from him again... stay tuned.
 

Offline VinceTopic starter

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #52 on: November 12, 2022, 07:48:29 pm »
4 days later..... today got an e-mail from Ebay, saying the seller received the connector I sent back to him.
So now let's see how long it will take for me to get my money back.  As soon as that's done, I order the board from him.

In the meantime, I just spent a few minutes on the things this evening.

I measured frequencies on the CPU board, to clear things up.... the CPU board is at the top of the stack of board, it's the only one I can probe while the programmer is running.

So as we said earlier, we have chrystals on that board. A 1.8432MHz one and a 8MHz one.

The othr than ROM and RAM, the big chips we have on the board are :

6502 CPU
6845 CRT controller
6522 VIA
6551 UART

So I checked the clock pins on all of these, and I got :

CPU = 1MHz
CRTC = 1MHz
VIA = 1MHz
UART = 1.8432MHz


So the 1.8432 clock is not for the CRTC it's for the UART, and all other chips run on 1MHz.... so you wonder why the hell didn't they fit a 1MHz crystal rather than 8MHz one and divide that by 8 ?
I don't know. Maybe other boards need more than 1MHz.

While I was at it I scoped the 16 pins of the header on the backplane which I suspect is for GPIB,  dreaming to see some activity, but no joy. Guess that's normal, it's a kinda static interface IIRC... unless some computer tries to talk to the programmer, the latter won't wiggle any of the data or control lines.
I have my school text book on GPIB, 25 years old now but still relevant of course so... will dig that book out to get a refresher on the subject.

I do have a GPIB computer but it's a vintage one that's stored in bits in boxes, and I don't have any room to give it a permanent "spot" in my house/lab. Just no room here.
If I want to set it up, I need to put it on the bench, no room esle where. But if the computer is on the bench... then there is no room left to put the programmer or whatever equipment I want to work on.
It's a pain... it will improve over time, but not anytime SOON, sadly.
« Last Edit: November 12, 2022, 07:56:16 pm by Vince »
 

Offline VinceTopic starter

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #53 on: November 19, 2022, 04:57:51 pm »
Seller took his pretty time, guess he was pissed, but he finally refunded me ! Was the last day, after that Ebay said I could contact them to let them "handle" it....

So as planned I ordered the video board from that guy immediately.
Should be here early next week I guess.

Can't wait, getting excited...
 

Offline VinceTopic starter

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #54 on: December 26, 2022, 09:03:52 pm »
Hello !!!

Happy X-mas with a bit of delay.... today I finally got round to trying out the video converter board !!! :-+

See pics.....

It came with no manual / instruction sheet or any documentation whatsoever.... so I had to improvise.

Luckily there is silk screen here. Power jack says it needs 5 to 12V, so I gave it 9V with lab power supply.
Looking good : a red LED lights up on the board, that's something...

So I hooked a VGA monitor to the VGA output on the board... looking again.

There are 4 push buttons on the board to let you communicate with the board, that's handy.

At power up it displays some chinese characters, then monitors shos "no signal" error.

I press the MENU button on the board and hey presto, a menu comes up on the screen, woohoo !!  :D

.... all in chinese though !  :palm:

I went through all the menus blindly, trying all options... until I found the much desired ENGLISH option, phew !

There is just Chinese or English available.

SO now I could understand the menus. It's quite simple.

There is one to adjust the geometry : H and V size and position.
Another menu to adjust the colours.
Another one to select the output resolution. Yes the board says it converts to VGA, but the menu actually offers you a few higher resolutions as well.

So it's all looking promising... so far.

So I now needed to figure out how to connect the video signals from the EPROM programmer, to the video board... and it's not clear at all.

My best guess is that connector next to the VGA input connector. The pinout indicated by the sill screen show H & V sync inputs, and RGB. Also a mysterious 'S' pin.... which I don't know about.
Also, that connector is the only one that fits the cable that's supplied with the board.

So I solder my wires and.... nothing. The monitor says NO SIGNAL, bummer  :palm:
At first I had soldered only the Blue input on the board, seeing as all colours were the same of course, EPROM programmer is monochrome. So I then thought well maybe the board still needs to see a signal on all 3 colour channels even if monochrome, so I soldered Red and Green as well.

Try again.... still no signal on the monitor  |O

So.... not impressed.

I will google to see if I can find some documentation on that board... here is hoping the programmer doesn't use some proprietary timings.... though even then, I would hope the board would at least display SOMETHING on the screen.... but no.

Well that's all you wiill get for a X-mas present from me I am afraid : nothing but my misfortune....


 

Offline VinceTopic starter

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #55 on: December 26, 2022, 09:38:45 pm »
Google found me this website about the board :

https://www.thegeekpub.com/280079/gbs-8200-manual-cga-to-vga-converter/

Apparently I wired the thing properly, that's a good start.

Says to use the SW button to switch from one input to the another.... did that, has zero effect on the screen not even a flicker.... suspicious.
Says to use the AUTO to get the board to automatically detect what type of video signal is being fed to the board.... again this has zero effect that my human sense can witness. Not looking good.

The menus don't let you specify manually what signals you are sending to the board, so if this AUTO button does nothing, I am screwed.

Did a quick sanity check.... scoped the RGB and HV sync pins.... yes, all my signals are still there....
However I noticed that with the connector disconnected, I get TTL level signals, 5V, but once connected to the board the amplitude drops to 2V or so ?!
Maybe that not normal and the boards fails to detect the SYNC signals because of that...





 

Offline VinceTopic starter

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #56 on: December 26, 2022, 10:09:57 pm »
Their website gives a couple suggestions in case like me you get no picture.

1) Modify the wiring harness to move the grey wire one notch, next to the yellow wire. Did that, no joy. So I put it back where it was.

2) Board can behave erratically if the power supply can't deliver 2 Amps at 5 Volts. Well I set my power supply to 9V and the board draws less than 200mA, it's not current limited, it seems happy.

So it draws barely 2 Watts versus 10 Watts ?! Maybe the chip is half kaput in there....

After doing that... somehow the SW button now shows signs of life ! When I press it displays the name of the inpu at the top of the screen... woohoo !
So I set it to " RGBHV " but still no picture, monitor says " NO SIGNAL ", bummer.

So now my two paths of investigation are

1) Can this board work with TTL level signals, and is it normal for it to drop the amplitude to 2V.

2) Does teh video signal of that EPROM programmer use some proprietary timing, in which case that board will probably never work as it appears to be designed for CGA/EGA only, to cater Arcade games.
It's not a general purpose converter where one could program custom timings and voltage levels and polarity, and enable interlacing or not. Maybe such converters exist.... if they do I guess they would be out of my price range for sure....


The saga continues....not giving up just yet...

 

Offline Robert763

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #57 on: December 26, 2022, 10:17:27 pm »
Hi Vince, see this manual too
https://docplayer.net/42901042-Cga-ega-yuv-to-vga-converter-gbs-8200-ver-3-4-manual.html
You have ver 4.
Just connect ONE of the video pins of the progrmmer to the converter board, I suggest to the Green (G) input. Each input has a 75R load so 3 in parallel is likely to overload the single output driver in the programmer.
Connect the 15kHz signal to Horizontal sync (HS) and the 50Hz one to Vertical sync (VS).

Trouble is you have an unknown specification signal so hard to tell what is wrong.

B.T.W when looking at the serial ports the data should be standard pin-out e.g. on pins 2 & 3.

Robert.
 

Offline Robert763

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #58 on: December 26, 2022, 10:21:26 pm »
Their website gives a couple suggestions in case like me you get no picture.

1) Modify the wiring harness to move the grey wire one notch, next to the yellow wire. Did that, no joy. So I put it back where it was.

2) Board can behave erratically if the power supply can't deliver 2 Amps at 5 Volts. Well I set my power supply to 9V and the board draws less than 200mA, it's not current limited, it seems happy.

So it draws barely 2 Watts versus 10 Watts ?! Maybe the chip is half kaput in there....

After doing that... somehow the SW button now shows signs of life ! When I press it displays the name of the inpu at the top of the screen... woohoo !
So I set it to " RGBHV " but still no picture, monitor says " NO SIGNAL ", bummer.

So now my two paths of investigation are

1) Can this board work with TTL level signals, and is it normal for it to drop the amplitude to 2V.

2) Does teh video signal of that EPROM programmer use some proprietary timing, in which case that board will probably never work as it appears to be designed for CGA/EGA only, to cater Arcade games.
It's not a general purpose converter where one could program custom timings and voltage levels and polarity, and enable interlacing or not. Maybe such converters exist.... if they do I guess they would be out of my price range for sure....


The saga continues....not giving up just yet...

Posts crossed. Does the input selection have CGA? It is worth trying ALL the input selections. he main chip used on the 82x0 is capable of all modes but it needs to be "told" what to do. Different versions / clones of the GBS82x0 firmware have different capabilities / bugs.

Robert.
 

Offline VinceTopic starter

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #59 on: December 26, 2022, 10:39:18 pm »
Fiddled with it some more.... was about to report that I did.... just what you suggested !  >:D

Board has  a VGA input connector, even though it's meant only for CGA/EGA.
So as a sanity check I wanted to see if the board could read VGA and output VGA...
So I plugged my Tek TDS544A scope to that board and.... it works fine, I have picture on the monitor !  8)

OK so that board is not dead, it is capable of reading video signals... just not MY video signals, grrr....

So I googled to double check what CGA signals should look like, especially voltage level-wise.

Google served me that site out of the blue :

https://gist.github.com/sigman78/706c5b8c7800e56aded87596fb5e75bb

There it says that CGA is 15.7kHz, but the programmer outputs 15.4 or something. Maybe the video chip on the board is not very tolerant to frequency deviations. Again no documentation so I don't know.
Anyway, that site says.. VERTICAL sync is 15.7kHz... vertical really, not horizontal ?! Strange... to me vertical is the slowest one, defining the frame rate, and the fastest clock is the horizontal that sweeps the lines  :-//   Anyway, nothing to lose, so entered humble mode thinking maybe I got it backwards somehow, and I swapped the H and V wires.... no joy. So I put them back to where they were.

So looks like there is indeed something that board does not like in my video signal.
Board has no documentation, but maybe I can find a datasheet for the chip itself, which would give me the tolerance on Sync signal frequencies, voltage level etc...

 

Offline VinceTopic starter

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #60 on: December 26, 2022, 10:43:56 pm »
Hi Vince, see this manual too
https://docplayer.net/42901042-Cga-ega-yuv-to-vga-converter-gbs-8200-ver-3-4-manual.html
You have ver 4.
Just connect ONE of the video pins of the progrmmer to the converter board, I suggest to the Green (G) input. Each input has a 75R load so 3 in parallel is likely to overload the single output driver in the programmer.
Connect the 15kHz signal to Horizontal sync (HS) and the 50Hz one to Vertical sync (VS).

Trouble is you have an unknown specification signal so hard to tell what is wrong.

B.T.W when looking at the serial ports the data should be standard pin-out e.g. on pins 2 & 3.

Robert.

Oops I missed your first post sorry.

Thanks for the link.

OK will try that.

Yeah I noticed the Serial port and also the I2C headers next to the MCU.
Maybe the serial port output useful data that could help me understand what the board is unhappy with exactly...but I don't have a computer in the lab just yet, so can't hook a terminal to that board.

Well, OK I could if I hooked my vintage computer to it, with Windows 2000 and 95, but that would require an enormous logistical effort... just no space to put it anywhere sadly.
An old Win95 laptop would be handy here for sure....

« Last Edit: December 26, 2022, 10:46:13 pm by Vince »
 

Offline m k

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #61 on: December 27, 2022, 09:05:46 am »
You should be able to see OSD menu.

CGA and EGA modes are sync polarity selected.

SW seems to be swapping between modes and not between connectors.

It says the left 5-pin connector is for JAMMA, no idea what kind of signal it has.
Included pinout picture has csync, so H+V.

I remember somebody had problems with one of these converters.
Can't remember how it went.

One other recollection is that CGA/EGA connector on the left uses different ASIC input pins than VGA.
If so then SW can pick connectors.

Your earlier picture with edge connector has no yellow, only RGBC and GND.
Maybe the converter needs that csync, one inverting gate chip can do that.

If you have a VCR you can try its YUV and see that the converter really does its down conversion.
(there sync goes with Y)
Advance-Aneng-Appa-AVO-Beckman-Danbridge-Data Tech-Fluke-General Radio-H. W. Sullivan-Heathkit-HP-Kaise-Kyoritsu-Leeds & Northrup-Mastech-REO-Simpson-Sinclair-Tektronix-Tokyo Rikosha-Topward-Triplett-YFE
(plus lesser brands from the work shop of the world)
 

Offline VinceTopic starter

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #62 on: December 27, 2022, 10:25:31 am »
You should be able to see OSD menu.

Not sure what you mean, I clearly said that the menu works just fine ?!  :-//

It says the left 5-pin connector is for JAMMA, no idea what kind of signal it has.

"JAMMA" from what I understand refers to something specific to the arcade game world.
It requires a special connector to interface the game with that board.
Earlier as you saw, I ordered this JAMMA connector by accident, instead of ordering the actual board... oops.


Included pinout picture has csync, so H+V.

" CSYNC " , is that a thing ? I didn't know about that...  I knew only about RGB + H + V sync signals, or composite which merges all the signals... but I didn't there existed a middle ground where the two Sync signals were merged and the 3 colours signals were still separate. Interesting...


Your earlier picture with edge connector has no yellow, only RGBC and GND.

I don't understand what you are referring to.


Maybe the converter needs that csync, one inverting gate chip can do that.

Not sure what you mean. The connector I used, as per the manual, has already H and V pins on it, it's meant to be directly interfaced to the CGA signals.

If you have a VCR you can try its YUV and see that the converter really does its down conversion.
(there sync goes with Y)

I did have a VCR but I tossed to make space.
Used to have a CCTV camera with a composite output, but I too tossed it to make space.

My digital camera maybe has a composite output built into its USB looking I/O port, just maybe, but I would need to find the manual and the adapter cable and I think they must be long lost....

I checked all my old hollow-state Tek scopes and not one of them as a video output ! I am very surprised and disappointed.... think I will return them to Tektronix.

OK maybe we are lacking gear here at Vince's lab to be able to do basic stuff like this... but that's nothing new, lab is a work in progress, as in.. slow progress...


@Robert : thanks for the manual, it's 90% identical to the one on the site I saw, but the 10% difference was interesting. It states the range of horizontal frequencies that it can accept : from 14+ to 16+ kHz, so that means anything close enough to 15kHz would work just fine, so I am good here.  However that manual too insists on calling the 15kHz clock.... VERTICAL. It drives me nuts.

« Last Edit: December 27, 2022, 11:19:38 am by Vince »
 

Offline VinceTopic starter

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #63 on: December 27, 2022, 11:49:58 am »
Just connect ONE of the video pins of the programmer to the converter board, I suggest to the Green (G) input. Each input has a 75R load so 3 in parallel is likely to overload the single output driver in the programmer.

Here is another day, troubleshooting continues....

OK so I disconnected red and blue. Amplitude increased to 2.6V on the green pin now, that's better...though I guess it's irrelevant, as any voltage is good enough for the colour channel,, I should still be able to see "something", and at any rate it's not going to cause the board to fail to output a VGA signal... so I guess all that matters is the amplitude of the H/V signals. These have a higher amplitude : 3.6V or so, one volt more than the colour channel.

Next step is... I could add a TTL chip, a buffer, on my breadboard. I measured the input impedance for the H/V input. It's not 75R it's a high(ish impedance, so a regular TTL buffer chip should have no problem giving proper amplitude output there. I measured the inputs at 1.8K and 10K+ .

OK let me do that and report...

One odd thing I noticed on that board : I measured the 75R RGB input resistors (directly across their terminals), they all measure 75R, fine. However if I measure the impedance between the RGB inputs pins and the round pin on the connector... I get 75R, 82R and 88R ?!  :wtf:

Still, not too concerned about that, as only the H/V signals are of importance in how the board reacts to my video input. Well, from my limited understanding I mean...

« Last Edit: December 27, 2022, 12:09:25 pm by Vince »
 

Offline VinceTopic starter

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #64 on: December 27, 2022, 03:10:56 pm »
Making progress here.

Did as I just said... pulled my bread board and added buffers to the H/V signals.
At first with a TTL chip.... got only 4.4V at the output, bummer.... then light bulb.. ah yeah I am rusty, TTL outputs have never been able of 5V to begin with.. there is a diode to Vcc internally, the best you can hope for is 4.4V or something, and that's what I get.
So instead I used a 74HCT chip, a 244 8 bit bus driver, because that's what I had.... not I get 5V at the output. Well, the first chip I used was defective, was doing strange things... the second chip was the winner.

Plugged the wiring harness to the video board. Amplitude drops a bit but not much. Most notably the leading edge of the 15kHz signal is now quite rounded, see pic.
The rising edge looks good for the most part, but the very top of it, between 4 and 5V, is quite rounded.

That's when I was scoping on the breadboard. I then scoped straight on the video board connector in case all that spaghetti wiring were degrading the signals badly... but no. Signals look exactly the same no matter where you look.

I got curious and searched which one of the millions SMD passives the H/V signals were connected to, on the board.
See pic. There is a long row of passives between the connector and the video chip.
I scoped these passives and quickly found where the H/V signals were routed to.
They go each to a 1K resistor. My signals get to one side of the resistors just fine, 5Volts, however on the other side, where it buggers off to the chip, the amplitude drops to 4V. Hope that's OK for the chip.

Anyway, signals had at last a proper amplitude, so I fired up everything...

... and we have improvement !

Now the board can detect something ! It can't make sense of it though, so it keeps cycling endlessly, displaying various kinds of garbage, but GREEN  garbage which is promising since I used the green colour channel... so clearly it's seeing my signal now, no doubt about that.

It cycles between 3 states mostly, from what I can see :

1) A solid green screen filling the entire screen.

2) long pause with a black screen.. probably it's thinking hard on what to do next

3) A "half solid" green screen... looks like a fine mesh, a woven fabric, something like that...

4) long pause with a black screen again

5) Now the interesting bit. On this part of its cycle, it displays a black screen with some green garbage flying by, that looks like it contains valid data, but garbled in the way you get when there is a timing issue.
Whenever it displays this, it lasts for a split second, half a second if even that, so my brain doesn't even have time to absorb what it's seeing... but after repeating the cycle many times (you never get the exact same garbage twice of course, depends on the pot luck of the timing at that particular time), I am 100% certain it displays intelligible ASCII text, and some geometrical shapes.
It displays a row of horizontal rectangles, just the outline of them, like you would expect from a status bar displaying place holders for menu options, and you would press function keys on the K/B to activate this or that menu option. That pleases me, it adds up.
All these rectangles are empty but sometimes I see one that has text in it (no time to read what it says though), in reverse video. So that's perfect, I like that a lot.
Also, on the next line, right below this line of rectangles, it displays some more text, a couple of words : " REMOTE "... followed by another word but I am not 100% sure what it is. Maybe " REMOTE CONTROL ".
Again I like that, because we know that the big brother of this programmer, once it's booted, gives you the choice of being used either remotely via a desktop computer, or locally using the K/B attached to one of its serial ports at the back.

So it all adds up nicely.

So the board clearly can make "some" sense of my video signals to display something interesting.... but it's not clever enough to get the timing 100% right.

Two possibilities here I guess :

- The programmer indeed uses non standard signals, some custom variation of CGA, but not compatible with off the shelf CGA monitors... just so that they could force you into buying their own, expensive of course, monitor...

- The board is defective. Indeed, it just keeps crashing and crashing and crashing. It's a disaster. Every time I power it up, I do get the chinese "splash scree" while its booting, then a black screen, and from there it's pot luck : half of the time the buttons won't be responsive and I can't enter the on-screen menu. Other times menu will work, but then when I exit it and try to use the SW and AUTO buttons... they won't be responding.. so as a quick sanity check I press the MENU button to see if the board is still alive and... most of the time it's not, menu doesn't work any more.
It's a disaster.

So I guess I could try to get a new board under warranty, see if that's any better. 

I guess it's also now time to read the 5 pages of messages on that French forum I was pointed to at the beginning of this saga, where a few people discuss their programmer, the big brother of mine. Maybe they talk about the display... and if not, I could post a message about it.

https://forum.system-cfg.com/viewtopic.php?t=5743

So I am making progress eh, what do you say ?!  ;D

« Last Edit: December 27, 2022, 03:40:29 pm by Vince »
 

Offline pcprogrammer

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #65 on: December 27, 2022, 04:31:03 pm »
Hi Vince,

I see you are having fun  :-+

Did you verify that the polarity of the sync signals is correct. The image of your scope screen shows them as going high for sync, but it might be that they need to go low.

Maybe worth a try.

Another option might be to use the CGA/EGA connector (the one with the 5 round pins), but for that you have to combine the sync signals like m k wrote about.

Cheers,

Peter

Offline VinceTopic starter

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #66 on: December 27, 2022, 05:16:55 pm »
From my google, all sites say CGA has separate H and V sync signals, tehy aren't not combined.

There is also consensus for plarity and voltage levels : TTL level, positive pulses, so I am good.

If I were using the polarity I doubt I would be able to see text being displayed I think, but I do  8)

One thing I could try, is to  try to get rid of the rounded rising edge. Seeing as the video board came to life when I fixed the amplitude of the signals.... it means it's picky about those signals. So maybe the rounded corner does upset it....

However I am not sure how I can fix that corner....  :-//


 

Offline VinceTopic starter

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #67 on: December 27, 2022, 06:54:46 pm »
Just done reading the 5 pages of that French forum discussing the 5000 model the bigger brother of my 3000U.
It's a gold mine of information.

It gets most interesting starting page 4, at this message :

https://forum.system-cfg.com/viewtopic.php?p=159652#p159652

Thread was initiated in 2014, then died that same year, al links are dead (images, documentation, disk images...  :palm: ) then was resurrected in 2020, not too long ago, by that guy linked above.
He clearly is a one of us... maybe he is on EEVblog I don't know...

He shows pics of his 5000... and I actually see his pics, the links are not dead yet  :phew:

It is most interesting... and most disheartening at the same time.

As you can see from the pics of the interior and the outside.... it's similar to mine except, the monitor and keyboard.... they are not meant to be plugged into connectors at the back, no... they are BUILT INTO THE FREAKING PROGRAMMER !!!!!!  |O

Mini CRT built-int, with its own driving board, custom keyboard with custom function keys that line up with the rectangles I saw / described earlier...
Custom floppy disk format as well.
This thing is just a giant custom thing through and through.

So now I can stop wasting my time trying to display an image...unless I can make my own converter, but I am not that good and can't justify the immense amount of time it would require me to do that anyhow.
Then I would have to make a custom keyboard as well... not knowing the protocol and details of the H/W interface used by the original one.

No... it's time to give up on this thing....

Or almost : a guy in 2020 said there is an MS-DOS software to drive the programmer from the serial port.
So that's how my unit was meant to be driven then. So my only hope is to find this S/W. I stand a better chance of winning the lottery or inventing a time travel machine.

Ah, also in 2020 there is this guy who says he worked on the development of this programmer, and has still some documentation and also the assembly code for the 6502 CPU. Wow.... maybe he can get hold of the MS-DOS S/W. Unfortunately he does not seem to respond to people... maybe he died. I hope not.

Ah yeah, if I can get the documentation for the GPIB port, maybe I could have some fun with that at least. Better than nothing.













 

Offline pcprogrammer

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #68 on: December 27, 2022, 07:39:48 pm »
Might be a bit of a stretch, but I found this site https://www.vandoeselaar.com/tinkering/modding-a-gbs-8200/ which writes about converting the video board to handle 240 pixel video.

It could be that the programmer has such a low res signal, and that the video converter as is can't handle it.

Offline VinceTopic starter

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #69 on: December 27, 2022, 08:17:58 pm »
Thanks for the searching !  :-+

... but it's way too involved for me, not my comfort zone at all. Not worth the time investment for me... need to be reasonable here.

IF someone had a video converter that's meant to be universal, where you get a control panel with knobs you can turns to modify every parameter on the fly to see in real time the effet on the screen, so you can quickly figure out what the parameters are.. then tell the converter to use that, then yeah, would be quick. But I doubt such a converter exists.

I did what I could with my scope and frequency meter / counter to figure as much as I could about this video signal... in vain. That's as far as I can take it, for now at least. Maybe once I retire and if all other projects are done... yeah maybe digging out that project would kee p me busy 'til I die...

But for now I will call it quis on the video side unfortunately.  Looking at the pictures I posted above, and trying to count characters on the screen, it looks like it'a got 42 columns and 26 lines... because the usual 40x25, so I guess they used the standard 40x25 timings and modified them a bit.
As for interlacing, looking at my scoping of the signal, and the pics of what it represents on the screen... I think we can at least say that it is not interlaced.... so that's a huge plus, makes things much simpler I guess. I guess if the engineer who worked on the project, who posted on that forum, is not dead and starts replying to people... maybe he has info on the details of the video protocol, or maybe I can find that out by studying the assembly source code he said he had, to see what the CPU writes in the CRT controller chip registers. Hopefully the source code is well commented...
Worst case I could spy the data bus and control lines of the CRT chip at boot with a logic analyzer to see first hand what the CPU writes to that chip...

OK so that's all for now on this project for now, I am stuck. Remains playing with the GPIB which I can't realistically do until my lab construction has been taken to the next level, with more space and a dedicated /permanent space for my vintage computer.

Then in  //, try to find a copy of that MS-DOS S/W to control the programmer via the serial port, my only hope.

So I will register on that forum and add my bit there....

 

Offline Robert763

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #70 on: December 27, 2022, 09:26:51 pm »
Hi Vince,
Try running the GBS8200 from a 5V DC supply, even if the board says 9 or 12V. I have a feeling there were boards with PSU issues. This may be the reliability issue.
If you have a smart phone or video recorder try recording the screen and playing it back with freeze frame.

Robert.
 
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Offline m k

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #71 on: December 27, 2022, 09:49:21 pm »
From my google, all sites say CGA has separate H and V sync signals, tehy aren't not combined.

Don't hang to that, it's just a name and were those board makers even born when that standard was on stage.
More commonly the meaning was just pixels, and not even including colors of them.

Your earlier picture with JAMMA connector has RGBC connection, so it is more likely a working one.
CGA/EGA is the name of one connector yes, but the connector has only 5 pins and one is named S, how you connect CGA or EGA with that?

14kHz H-sync is so low that your signal most likely fits.
But if you connected through VGA connector and the board expects something else then you obviously have a scrambled picture.

Occasionally not working buttons can be so that when the board starts its conversion some buttons are disabled.
Advance-Aneng-Appa-AVO-Beckman-Danbridge-Data Tech-Fluke-General Radio-H. W. Sullivan-Heathkit-HP-Kaise-Kyoritsu-Leeds & Northrup-Mastech-REO-Simpson-Sinclair-Tektronix-Tokyo Rikosha-Topward-Triplett-YFE
(plus lesser brands from the work shop of the world)
 
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Offline m k

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #72 on: December 28, 2022, 07:40:31 am »
Robert linked a manual,
there page 6 has frequencies.
Only B has lower frequencies, C and D are the highest only.
The board has also 3 connectors for those.
If all connectors are equal then why three sets.

Page 3 has features, there are also proportional YUV resolutions missing from page 6.
Applications have also some oddities, like own lines for plain CGA and EGA.

Included booklet is v3.0.
It has RGBS for VGA connector input, not very standard.
(later pinout can have CSync through HSync, Green can also include SoG)
8-pin connector is RGBS only.
5-pin connector has EGA and CGA inputs, not very standard again.
Specifications then has lower H-freqs through 5-pin P3 only and RGBS is totally missing.
Very clear.

It's possible the board is not supporting real CGA or EGA at all.
Though it is supporting CGA and EGA resolutions but only with always same polarity composite sync.
8-pin connector has markings for separated H and V syncs but specifications is not supporting lower frequencies through it.

Earlier pictured JAMMA connector is connected to 8-pin P10 and it uses four rightmost pins from the booklet picture.
(pins are GND GND VS HS S ? G ?)
If JAMMA signal is not hi-res then booklet's specifications is inaccurate and P10 will accept lower frequencies, but how those VS and HS are treated is still unknown.
Though booklet specifically advises how separated JAMMA syncs should be connected.

Before the big chip there are so many passives that all signals can be separated.
Are VGA HS and 8-pin HS the same?
5-pin S and 8-pin S also?
Advance-Aneng-Appa-AVO-Beckman-Danbridge-Data Tech-Fluke-General Radio-H. W. Sullivan-Heathkit-HP-Kaise-Kyoritsu-Leeds & Northrup-Mastech-REO-Simpson-Sinclair-Tektronix-Tokyo Rikosha-Topward-Triplett-YFE
(plus lesser brands from the work shop of the world)
 

Offline VinceTopic starter

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #73 on: December 28, 2022, 02:37:49 pm »
@mk : thanks for that PDF, it's yet one more notch better than the previous one. In this one we have a nice table at the bottom of page 3 which explains better what each connector can do or not do.

Thanks for trying to help with this board, I appreciate... but honestly the more you post about it, the more confused I become. It's a huge mess.
BUT..... I thought I would search Youtube Videos to see if I could find interesting about this board and sure enough I did.

It's now much clearer.  So to summarize all my findings and conclusions on this whole video situation, he goes

1) Yes sorry mk, CGA is not composite sync, just is not.

2) CGA is only 50 or 60 Hz, not 40+ Hz like my programmer is using.
Other than that the sync signals are of the same type : TTL positive pulses. Pulse width does not conform to CGA standard though, but is in the same ballpark  (single digit micro seconds)

2) That video board is NOT designed for CGA monitors ! :palm:  It's designed to work from the CGA otput of arcade games... which apparently is not real CGA. It's got composite sync signal. The board is meant to work with composite signals.

3) This board is old, well known, it's the cheap route for CGA to VGA. However what's also known is how crappy and unreliable these boards are. One guy even ordered 3 of these boards in a row and all had some kind of problem... so mine is no different.


Now for the "hope" part : the guys who like me tried to get that board to accept REAL CGA signals.. eventually managed to do it. They merged the H and V signals to make a composite sync signal (which they fed to the appropriate pin on the 5 pin connector on the edge of the board).

Thanks goodness they even said what they did to create this Csync signal : nothing more than a  XOR logic gate ! That works apparently...it gives you a picture. However guy said he then inverted the Csync signal . changed polarity, and it looked even better.  Honestly from his video, it looked just fine without inversion but hey...

So... knownig all that...  I can add the XOR gate knowing it should wrok IF I had a CGA signal. But I don't. However the main differences seems to be the slightly different Hsync frequency which the board should be able to cope with, but most importantly the Vsync frequency which is quite lower than CGA, so not sure the board can handle that. However I guess it should probably give us a better picture than what we have right now, so it's still worth a try.

@ Robert :

I adjusted the supply to 5V but still no joy, it crashed just as happily. Was worth a try...

Freeze frame : my 10 year old smart phone is not the best tool for that.. it's buggy as hell, I don't even know if it can do video (it's already useless for pictures...), and if it did I have zero storage space left to record a video.  BUT... well I have already made plenty of video clips with my still camera so I used that. I recorded 10 minutes of the board cycling, so I could get a handful of "events", hoping some of them would be exploitable.
I uploaded the raw footage on YT :



I then played it back at the slowest speed, x0.25 and even then it was difficult to freeze frame at the correct moment, because the events last only a split second and within that split the second the content is not steady, but rather changing rapidly as you see the video board trying stuff out in real time before yours eyes...

Example of the crap you see flying by :



Still, you brought me luck, it was a good idea, and I managed some cool shots, see below.
It's perfectly consistent with the pictures I posted earlier of people's working 5000 models.
What struck me though is that the text is in English rather then French for all the other people that have these programmers... so maybe it was sold to UK company back then, then found its way back to France years later. Or maybe it's just a dead backup battery so it uses default valuesd and it so happens to be English rather than French. Who knows...

1) Right at power, when the CPU is booting from its ROM I would say, it displays the Micropross logo, then some text to tell you to insert the boot floppy, then a few  error codes.



What I find odd though, is that if you pay attention, and even though the pic is blurry.... the text appears to mention "ROM5000" but I have a 3000 model !
So could it be that even the firmware in the 3000 is the same as that of its big brother the 5000 ? So that means that maybe I could get it to boot a 5000 system disk and have more features to play with... It's very odd and intriguing at the least.

2) Then once it's booted, it displays always the same image, again perfectly consistent with other's pictures : a row of five "buttons" / rectangles.
Here however the text and options displayed clearly show that it's a "headless" unit not a fancy 5000 : look, the menu bar has zero option, only the last / fifth button  is labelled, and it just says "END". And the text below below the buttons says : " REMOTE CONTROL " (as I thought it did)




... because well, this unit is only meant to be operated via the serial port with an MS-DOS S/W. You are not supposed to have a K/B to "press" buttons on the menu bar, never mind have a screen to see what the programmer displays..... so it makes sense not to offer the user any options that he could not see nor select anyway...

Yeah it all adds up, I am happy with that !  :D


OK so now I will add that XOR gate to the breadboard to create a Csync signal and see if that helps....

« Last Edit: December 28, 2022, 02:43:04 pm by Vince »
 

Offline Robert763

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Re: Vintage chip Programmer : " Micropross ROM 3000U "
« Reply #74 on: December 28, 2022, 05:46:03 pm »
You can custom program the scaler chip on the GBS82x0 see
https://www.vandoeselaar.com/tinkering/modding-a-gbs-8200/
Robert.
 


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