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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: curtis on August 02, 2017, 11:47:45 PM
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Finally got my 2000 back on the workbench and now it won't boot.
My symptoms are a black screen and 10 short blinks and 1 long blink on the power LED.
I've swapped out both the cpu and the ROM for known goods and no joy.
Checked voltages on the power supply and they're good.
I've got an Indivision installed and I don't even get the "splash" screen from it.
Suggestions?
Oh, it's a rev 6.2 motherboard.
Right now there are no boards installed at all. It's basically bare metal with only a floppy drive.
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http://www.amiga.org/forums/showthread.php?t=20817
Check post #7
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Try pushing/reseating all socketed chips especially Agnus. Might also be bad contact at cpu socket. Try cleaning it with contact cleaner.
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Finally got my 2000 back on the workbench and now it won't boot.
My symptoms are a black screen and 10 short blinks and 1 long blink on the power LED.
I've swapped out both the cpu and the ROM for known goods and no joy.
Checked voltages on the power supply and they're good.
I've got an Indivision installed and I don't even get the "splash" screen from it.
Suggestions?
Oh, it's a rev 6.2 motherboard.
Right now there are no boards installed at all. It's basically bare metal with only a floppy drive.
I have one of my A1500s that performs exactly the same. I have to switch off from the back and switch back on again. A softboot wont work. I just have to fire up again. Are you sure the video connector is working and is seated properly. Never used an Indivision. I found that the problems with the 2000 are mostly related to cards not seated properly or the main CPU. It needs a good connection so clean and check. That would generally throw up a colour but you never know. Dust off the board with the case out and just reseat but be very careful.
I've had a tricky time with 2000s this year and I've had a variation on your issue. All though were resolved with just minor issues to connectors. I switch on four of them every day just to check and they all work. Like I say that one 1500 sometimes needs a reset from the power switch to get her working. More annoying than a real problem.
Good luck.
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@amiman99 Guess I'll have to find some DRAM chips and give it a whirl.
@JuMa Tried that several times. No joy.
@scuzzb494 Repeated power cycling doesn't do anything. Double checked the INdivision and no joy there. Firmly seated.
Looks like amiman99 has the right idea. Now to order the chips!
Sigh...
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has the battery leaked?
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has the battery leaked?
Battery is long gone.
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@amiman99 Guess I'll have to find some DRAM chips and give it a whirl.
@JuMa Tried that several times. No joy.
@scuzzb494 Repeated power cycling doesn't do anything. Double checked the INdivision and no joy there. Firmly seated.
Looks like amiman99 has the right idea. Now to order the chips!
Sigh...
I wouldn't put my money on chip RAM problems (the system should be alive enough in that case to produce a green screen instead of a black one) but a quick test without any extra chips is:
desolder RP502 and replace with equivalent individual resistors, such that Agnus RAS0 gets routed to U505-U508 and RAS1 gets routed nowhere (i.e. the U501-U504 bank, where a chip problem would most likely be anyway, is cut off). See the schematics (http://www.amigawiki.de/dnl/schematics/A2000_R6.pdf) for further clarification.
That way, you relocate the base chip RAM to the (most likely) good U505-U508 RAM bank. If it works, you know there's a bad chip somewhere in U501-U504.
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Don't where you got green screen.
My startup screen is BLACK. Just like nothing is firing. Not even the Indivision splash screen.
And replacement RAM chips are on the way.
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Any difference from the composite video out?
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Don't where you got green screen.
From the standard error-colours the Amiga uses - when something's wrong with chip RAM in general (RAM chips, Agnus or possibly other custom chip, data path to chip RAM) it presents a green screen, not a black one.
Thankfully ROM is not behind the chip RAM buffers, so a problem in the chip RAM subsystem does not affect ROM code execution. Therefore if the problem is chip RAM restricted, the ROM code will still execute, detect the problem and switch to green error colour. It wouldn't normally stay black.
My startup screen is BLACK. Just like nothing is firing. Not even the Indivision splash screen.
Yes, you were perfectly clear about that. Which is why I suspect it's not the RAM chips (see reasoning in previous post and further explanation in this one).
The Indivision doesn't display its splash screen from chip RAM anyway, but from its internal buffer, so its absence is not an indicator of chip RAM fault.
And replacement RAM chips are on the way.
Let's hope then I'm wrong and the new chips will sort the problem out :-)
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Guess this thread will go dormant for a couple of weeks while waiting for the chips to come from China!
Stand by to stand by...
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Guess this thread will go dormant for a couple of weeks while waiting for the chips to come from China!
Stand by to stand by...
Hey Curtis sorry for your problems. I always hate when something is wrong with my amigas! Is that the board I sold you? I was happy to see you having a nicely built a2k from it.
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Guess this thread will go dormant for a couple of weeks while waiting for the chips to come from China!
Stand by to stand by...
wish you had asked curtis, i have loads of 256x4 dip ram chips(i think rev 6 uses those?)
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wish you had asked curtis, i have loads of 256x4 dip ram chips(i think rev 6 uses those?)
Hey mechy do you have DIP chips for a commodore a2058 board?
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My symptoms are a black screen and 10 short blinks and 1 long blink on the power LED.
I'd second the suggestions from BLTCON0, it doesn't sound like a typical memory access problem.
@mechy - yes, the rev6 board uses the 4x256k DRAMs, it's the rev4 board that uses the 1x256k. The many you've supplied me in the past have all been great thanks.
@curtis - before ripping out all the existing DRAMs (and possibly causing more problems in the process), you might like to make a few more diagnostics. For a start check if the system if even getting as far as the memory test. An easy way to tell is use an oscilloscope to see if the memory write enable line (pin 3 on any of the DRAMs) is strobing low. As I recall, you'll see at least two low-going strobes at about 1µSec duration. If it's not doing this, you're certainly not going to get anywhere by replacing the DRAMs.
John H's DiagROM (http://www.diagrom.com/) is particularly useful at this point. If you don't see any serial data out immediately at power on, you've got some other low-level problem going on.
As others have said, if there's been battery corrosion in the past, it's common to get corrosion in/around pin 1 of the 68000 CPU socket which often causes the machine to do nothing at power on, or give you some nondescript error. Cleaning it rarely results in it becoming usable unless the corrosion is very minor. If any of the socket contacts appear green/blue or tarnished/dark grey in colour (should be bright silver) then the entire CPU socket need to be replaced.
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Hey mechy do you have DIP chips for a commodore a2058 board?
I only have 256x4 and 1mx4...i think the 2058 uses 1mx1? and i don't have any.
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Finally got my 2000 back on the workbench and now it won't boot.
My symptoms are a black screen and 10 short blinks and 1 long blink on the power LED.
I've swapped out both the cpu and the ROM for known goods and no joy.
Checked voltages on the power supply and they're good.
I've got an Indivision installed and I don't even get the "splash" screen from it.
Suggestions?
Oh, it's a rev 6.2 motherboard.
Right now there are no boards installed at all. It's basically bare metal with only a floppy drive.
Curtis, check agnus, make sure its the right one and make sure all motherboard jumpers set right. check for cracked socket and bad socket pins.
has the psu lost TICK signal?
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Wish I had an o'scope to do some of the testing mentioned above, but I don't.
Agnus has been replaced with a MiniMeg. Tried pulling it and replacing with a 1MB Agnus with no joy.
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Like mechy suggested it might be problem with TICK signal at PSU. Try setting jumper J200 to internal TICK.
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So far as I can find out the 10 blinks of the power light is Kickstart 3.x thing. Have you got KS3.x installed?
Apparently it's to give you a chance to get a debug dump from the serial port.
I don't therefore think the number of blinks on the power light really means anything here.
I've also found an indication that a black screen means no CPU detected. I didn't find anything pointing to RAM.
edit to add:
You may find this link useful. Seems to suggest the black screen could also be CIA chip related.
http://www.lemonamiga.com/forum/viewtopic.php?t=13978
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So far as I can find out the 10 blinks of the power light is Kickstart 3.x thing. Have you got KS3.x installed?
Apparently it's to give you a chance to get a debug dump from the serial port.
I don't therefore think the number of blinks on the power light really means anything here.
I've also found an indication that a black screen means no CPU detected. I didn't find anything pointing to RAM.
Debug dump from serial port, really? What speed and other settings should one use to get that from an A2000 with ROM 3.1?
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Debug dump from serial port, really? What speed and other settings should one use to get that from an A2000 with ROM 3.1?
9600 baud, 8bits, no parity. Press delete on the remote terminal to invoke the ROM debugger.
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9600 baud, 8bits, no parity. Press delete on the remote terminal to invoke the ROM debugger.
Cool. Is this available from 3.0 or 3.1?
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Cool. Is this available from 3.0 or 3.1?
I think it is 3.0 as this link seems to suggest v39 which I think was 3.0:
http://amigadev.elowar.com/read/ADCD_2.1/Includes_and_Autodocs_3._guide/node01E3.html
Look near the bottom.
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Tried the J200 switch. No change.
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Have you tried it COMPLETELY bare bones? No Indivision and no floppy.. just the PSU, motherboard and video output (B&W composite if you don't have compatible monitor)?
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Could it be that the crystal driving the processor is not connected properly or defective?
Long shot, but if you have a scope to check the crystal outputs / tick signal, and it isn't giving Mr CPU any timing signals, that might explain why the Amiga thinks it doesn't have a processor?
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That's the way I test. Always.
Have you tried it COMPLETELY bare bones? No Indivision and no floppy.. just the PSU, motherboard and video output (B&W composite if you don't have compatible monitor)?
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Don't have an o'scope.
Could it be that the crystal driving the processor is not connected properly or defective?
Long shot, but if you have a scope to check the crystal outputs / tick signal, and it isn't giving Mr CPU any timing signals, that might explain why the Amiga thinks it doesn't have a processor?
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Well, well. Looks like my A2000 died as well. First random freezes then just black screen. It has vampire intsalled. I removed vampire and installed 68k and rom. Now at power up it goes normally to insert floppy screen but when starting to load a game it freezes. If reset after that it (sometimes) goes to green or red screen and resets itself.
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Welcome to my horrible, terrible, very bad day!
Well, well. Looks like my A2000 died as well. First random freezes then just black screen. It has vampire intsalled. I removed vampire and installed 68k and rom. Now at power up it goes normally to insert floppy screen but when starting to load a game it freezes. If reset after that it (sometimes) goes to green or red screen and resets itself.
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Welcome to my horrible, terrible, very bad day!
Don't jinx us other A2000 owners! :(
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Trying not to!
BTW, just swapped out both CIA chips.
No change.
Sure hope those RAM chips get in soon...
Don't jinx us other A2000 owners! :(
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That's the way I test. Always.
Ok, you indicated that you didn't see the Indivision splash screen so that led me to believe it was still there. At least we can say why you don't see it... because it's not installed :roflmao:
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:destroy: :python: :flame:
Ok, you indicated that you didn't see the Indivision splash screen so that led me to believe it was still there. At least we can say why you don't see it... because it's not installed :roflmao:
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Cool. Is this available from 3.0 or 3.1?
The ROM debugger is available since ever, but it became much less useful with 3.0. Before that, the ROMWack had a more or less textual interface, but SAD (introduced in 3.0) only accepts binary. I have not yet seen an external program that can talk to SAD to make it a reasonable debug tool.
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Curtis
2 questions
1. Is the PowerLed Dim or Bright?
2. Hook up a keyboard and press cap locks 10+ times does the caps lock light still light?
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Curtis
2 questions
1. Is the PowerLed Dim or Bright?
2. Hook up a keyboard and press cap locks 10+ times does the caps lock light still light?
Since I have the same problem... In my case power led is bright. Caps lock lights about six times then it stops. Does it mean something?
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It
Since I have the same problem... In my case power led is bright. Caps lock lights about six times then it stops. Does it mean something?
Yes it means the CPU isn't started up completely. Look close at power LED the second you press power on. If the ROM are active the first instructions they give is to brighten the power LED. It should go to to bright a sex nd after power is on.
Check your CPU socket for green or if you have been using a vampire in it you may have bent them out to much. I've had to replace several 68k sockets for vampire owners lately.
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Reason #69 that the Vampire folks need to have plenty of expansion slot adapters around!
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Reason #69 that the Vampire folks need to have plenty of expansion slot adapters around!
I'm building several when the boards get here to sell actually.they will be under $40 shipped too.
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Okay,the RAM chips came in.
Placed them very carefully and snugly over the originals and fired it up. Nothing changed. Also, none of the chips seem any warmer or cooler. All about the same temp.
Tried 4 different cpu's, all known good, and got the same result.
Tried the Caps Lock mentioned above and got to 6 or 7 and it stopped responding.
Summary:
1. Computer has ONLY a Indivision ECS installed as I no longer have a monitor that can display Amiga natively.
2. On power up I get 10 short blinks and 1 long blink on the Power LED. Nothing else. No other sign of life.
3. So far I have replaced BOTH CIA chips, the cpu, Agnus, and doubled checked all jumpers including swapping the TICK to the display instead of the power supply.
NOTHING IS WORKING.
I do NOT have an o'scope so I can NOT check signals.
Suggestions?
Thanks,
Curtis
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Take out the indivision and connect the composite b&w to a TV.
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Okay,the RAM chips came in.
Placed them very carefully and snugly over the originals and fired it up. Nothing changed. Also, none of the chips seem any warmer or cooler. All about the same temp.
Tried 4 different cpu's, all known good, and got the same result.
Tried the Caps Lock mentioned above and got to 6 or 7 and it stopped responding.
Curtis
Curtis if caps lock doesnt make it to 10 times its CPU problem. Probably the socket. Clean the socket with iso and a toobrush see what happens. Does the power LED stay dim or get bright?
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def take out the indivision and try it as the other poster said too. also on boot up does the Cap lock key flash?
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It
Check your CPU socket for green or if you have been using a vampire in it you may have bent them out to much. I've had to replace several 68k sockets for vampire owners lately.
I replaced cpu socket. At power on it goes to insert floppy screen but after 60 seconds or so it freezes. If reset then screen stays black or goes to white. If I turn power off and wait little longer like 10 minutes it boots to floppy screen and freezes again after a while.
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I replaced cpu socket. At power on it goes to insert floppy screen but after 60 seconds or so it freezes. If reset then screen stays black or goes to white. If I turn power off and wait little longer like 10 minutes it boots to floppy screen and freezes again after a while.
Do you have another kick-start ROM you can try?
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IF I had a composite crt, I would be happy to do that. Unfortunately, I do not.
Take out the indivision and connect the composite b&w to a TV.
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Do you have another kick-start ROM you can try?
Tried 3.1 rom no change. Just noticed that it actually doesn't completely freeze but disk animation slows down to crawl. Also drive click slows to about once per 30sec.
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IF I had a composite crt, I would be happy to do that. Unfortunately, I do not.
Understood.. I had to drag my Amiga out and connect it to our living room TV.. wife wasn't thrilled, but she got over it.
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I'm starting to suspect bad contact or trace somewhere. If I lift the board a bit or even tap disk drive instant restart/freeze. If trying to load a game it loads few secs but then stops.
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I don't think this is your problem, but it couldn't hurt to try -- another power supply?
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I'm starting to suspect bad contact or trace somewhere. If I lift the board a bit or even tap disk drive instant restart/freeze. If trying to load a game it loads few secs but then stops.
Remove every chip, clean if necessary and inspect all pins and sockets. it smacks of bad contacts, pay attention especially to Agnus(cracked sockets are common).
The cpu socket also.
I've had a a3000t that had a bad socket that was broken underneath between board and socket and you couldn't see it at all. really fun to find it, i spent a hour with it running prodding with a plastic stick on sockets and chips till i made it crash. It was a factory defective socket that just happened to act up when i got the machine.
Bad psu voltages on the +5 rail can also make a machine crash and or boot random.
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IF I had a composite crt, I would be happy to do that. Unfortunately, I do not.
a 1084 thru rgb would be great but i guess no 1084 either?
These little 7" lcds are great for test monitor, they take pal/ntsc COMPOSITE in and do 4:3 usually.
http://www.ebay.com/itm/7-LCD-Car-Rear-View-Monitor-Wireless-Parking-Night-Vision-Backup-Camera-Kit-/272788663880?hash=item3f8378ae48:g:rIAAAOSwighZgpbJ
u can probably find a better priced one, its just the link i grabbed first.
heres another:
http://www.ebay.com/itm/7-TFT-LCD-Digital-RGB-HD-Screen-Car-Monitor-For-Rear-View-Camera-DVD-GPS-VCD/271849458345?_trkparms=aid%3D555014%26algo%3DPL.DEFAULT%26ao%3D1%26asc%3D41375%26meid%3D8717290109ab438fba9c941dd9a01b8f%26pid%3D100507%26rk%3D1%26rkt%3D1%26&_trksid=p2045573.c100507.m3226 (http://www.ebay.com/itm/7-TFT-LCD-Digital-RGB-HD-Screen-Car-Monitor-For-Rear-View-Camera-DVD-GPS-VCD/271849458345?_trkparms=aid%3D555014%26algo%3DPL.DEFAULT%26ao%3D1%26asc%3D41375%26meid%3D8717290109ab438fba9c941dd9a01b8f%26pid%3D100507%26rk%3D1%26rkt%3D1%26&_trksid=p2045573.c100507.m3226)
good luck on the 2000,if all fails change the oscillator.
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I am also leaning towards trying to remove every chip and clean with a toothbrush and 99% IPA. If you have a good disk washer after the chips are removed you can use it to run the board through a cycle as long as you let it sit on its side at an angle and dry out ofter for a few days.
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I now use one of these:
https://www.amazon.com/gp/product/B00M4JY722/ref=oh_aui_detailpage_o07_s00?ie=UTF8&psc=1 (https://www.amazon.com/gp/product/B00M4JY722/ref=oh_aui_detailpage_o07_s00?ie=UTF8&psc=1)
to convert the B&W composite to something I can show on my monitor (mine has HDMI which is connected to the VA2000/CX and VGA which is connected to the device above).
I'm not sure its worth going out to spend the money on it as it's just a shot in the dark that you might get something useful out of removing the Indivision. I got it because I was tired of dragging the Amiga back and forth between my office and the living room.
I assume that you've tested it with it removed and it still does the same flashing thing.. don't need a monitor hooked up for that.
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If you have a good disk washer after the chips are removed you can use it to run the board through a cycle as long as you let it sit on its side at an angle and dry out ofter for a few days.
Would you run it without any detergent?
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Would you run it without any detergent?
Right, just water. If your water is hard I would be sure to use some IPA right after to get as much water out before drying. It wont hurt it, but makes cleanup harder if it puts a lot of mineral deposits on it.
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Well, I tried to utilize a machined pin socket and plug that into the cpu socket, with the cpu, and it didn't change a thing. Really starting to get exasperated with this thing!
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Have you tried this:
https://www.youtube.com/watch?v=E3YEKqEqleg
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Have you tried this:
https://www.youtube.com/watch?v=E3YEKqEqleg
I had the same problem: http://www.amiga.org/gallery/index.php?n=2390
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Sadly, my soldering skills have deteriorated to the point I really can't do that fine of work anymore.
Looking at everything, there doesn't appear to be any green from the battery which has been removed.
None of the joints look bad. Of course, that's looking at it with only a Mark I eyeball.
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I am also leaning towards trying to remove every chip and clean with a toothbrush and 99% IPA. If you have a good disk washer after the chips are removed you can use it to run the board through a cycle as long as you let it sit on its side at an angle and dry out ofter for a few days.
That did it! I removed all socketed chips and put it on a dishwasher. Then cleaned with IPA. Also resoldered everything in cpu area. It's been up for a day running demos and stuff. No issues so far. Hopefully it will last.
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That did it! I removed all socketed chips and put it in a dishwasher. Then cleaned with IPA. Also resoldered everything in CPU area. It's been up for a day running demos and stuff. No issues so far. Hopefully, it will last.
I've got several working again after a good clean like that. Oxidation causes resistance values to change, getting all off and cleaning sockets helps a lot. A more drastic measure is a complete resocket and replace all the components in the battery area.
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I just ran into this issue - blank (real black) screen, one brief flicker then back to black. Power LED blinks like the system just crashed, but blinks out a pattern of 10 short blinks and one long.
I replaced all the CHIP RAM thinking it was that, but what it really was turned out to be a bad single-wipe socket(kind of a redundant statement, they're all bad by default) on the U300 CIA.
Moral of the story: If chip swapping doesn't work, get rid of all the single-wipe sockets before you go any further, even if they look good.