Electronics > Repair
Vintage chip Programmer : " Micropross ROM 3000U "
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Vince:
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
Vince:
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.
Vince:
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.
Vince:
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...
Vince:
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....


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