User avatar
Tandrews_ny

Posted Tue Feb 18, 2020 6:59 pm

I have an Amiga 2000. I was able to get the board working but it had battery damage, so I went over it with flux and braid. Following that I cleaned the board with vinegar to make sure I've neutralized the alkali. Dried it out and tried to boot it...nothing. Found one data line missing, but i've jumpered it.

I've checked the connections between u103-106, kickstart, agnus from the CPU. Checked clock signal, getting 7mhz.

Verified RESET goes high after boot.

I'm at my wits end here. I know its something stupid, but I lack the skills to fix it or feel I do. Any help would be appreciated. If you're able to fix it, I have no problem paying for it, long as its reasonable.

User avatar
obitus1990
New Orleans, LA, USA

Posted Tue Feb 18, 2020 9:27 pm

What does the power LED do when you turn it on? Does it start dim, then go bright, or does it stay dim?

Will the machine boot DiagROM? You can buy one on eBay pre-programmed from gglabs and swap it out with your kickstart, and then connect your amiga's serial port and to your PC (with a serial-->USB adapter and a null modem cable). Load up PuTTY on the PC and see what the output is.

Also, after you neutralized with vinegar, did you wash the board off with distilled water, blow out all the water with compressed air, then let the board dry out for at least a day with a fan blowing on it (or after using a hair dryer on it after compressed air)? Any vinegar residues left behind can be problematic, as well as trace amounts of water which can cause a short.

User avatar
Tandrews_ny

Posted Tue Feb 18, 2020 9:55 pm

Swapped every chip into my a500. Boots to ks2.0

power led starts bright, stays bright. I found it would dim if the low pass was on? Or off...

I don't have a diag ROM. Looks like it would take quite a while to arrive.

I should say the entire board wasn't soaked in vinegar. I used a toothbrush, let it drain and rinsed again. The board was thoroughly rinsed with alcohol and left to dry overnight, almost 18 hours. I also did blow as many sockets out. There was no trace of water before powering on.

User avatar
grshaw

Posted Wed Feb 19, 2020 5:57 am

What about your PSU - is that providing the correct voltages on each of the wires?


User avatar
obitus1990
New Orleans, LA, USA

Posted Wed Feb 19, 2020 11:38 am

The power LED should start dim and then go bright about 1 second afterwards. I've never heard of a scenario where it starts and stays bright. Only the other way around (starts and stays dim). Do you have an EPROM burner? DiagROM is open source and freely downloaded here. All you need to do is program it onto the proper eprom, an AM27C400 and put it into the kickstart socket.

Also, what happens if, after turning it on, you repeatedly hit the CAPS LOCK KEY, turning it on and off , say 20-30 times? Does the LED ever get stuck to the ON position on the caps lock key, or, can you continuously turn it on and off by repeatedly pressing the caps lock after numerous presses?

User avatar
Tandrews_ny

Posted Wed Feb 19, 2020 1:23 pm

obitus1990 wrote:
Wed Feb 19, 2020 11:38 am
The power LED should start dim and then go bright about 1 second afterwards. I've never heard of a scenario where it starts and stays bright. Only the other way around (starts and stays dim). Do you have an EPROM burner? DiagROM is open source and freely downloaded here. All you need to do is program it onto the proper eprom, an AM27C400 and put it into the kickstart socket.

Also, what happens if, after turning it on, you repeatedly hit the CAPS LOCK KEY, turning it on and off , say 20-30 times? Does the LED ever get stuck to the ON position on the caps lock key, or, can you continuously turn it on and off by repeatedly pressing the caps lock after numerous presses?
Yeah. It doesn't start dim at all, always bright. Like I mentioned, I've tested ALL sockets chips on another board, boots and reads floppy.

I have a burner but not that big nor the EEPROM for it.

I can try the keyboard thing.

I have the reproduction board design, so I can check whatever you need me to do.

User avatar
nadoom

Posted Fri Feb 21, 2020 2:38 pm

Hi
Sorry you are having so much trouble.

I'd make sure that you have neutralised all the acid using vinegar as it can keep corroding.

With diagrom.. I went down this route..
I got the bits on eBay which was this..
TL866II PLUS High Speed USB Universal programmer..

And
The adaptor for the ROM as it won't fit by default ..
27C322 27C160 27C800 27C400 Adapter for TL866 Minipro (all rev) EPROM Programmer

I'm a total noob but managed it in the end.. if you are in UK I can burn it for you and send it to you ..

Also worth checking out Jan beta on YouTube as he had an a2000 with battery damage I think.

Hope you get it sorted

User avatar
Tandrews_ny

Posted Sat Feb 22, 2020 3:45 pm

Still having issues sadly. I found a few broken address lines but still nothing.
I have a diag rom and as I suspected, nothing boots. CPU goes into halt.
STarting to feel a bit down.

User avatar
sportbikepilot

Posted Sun Feb 23, 2020 1:26 pm

Step away from it for a few days. I go through the same feeling when I can't get something to work properly. I find when I start getting fussy or annoyed, I tend to make problems a lot worse.

Best advice I can offer from my experience is set it aside for a few days and go do something else. Come back to it with fresh eyes and a clear mind, and you'd be surprised what you find and how quickly you find it.

Chris





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