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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Unit21 on February 05, 2004, 01:33:43 AM
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I got a ´broken´A3000 the other day...
When I power it up the screen is flashing like a christmas-tree.
I have seen a yellow screen a few times, but it is mostly the red one that flashes one or two times.
Then the machine resets and the insert disk screen shows up.
If I leave it like this it will run happily for hours...
But if I insert a disk or try to connect a harddrive to boot from it crashes 9 out of ten times.
Usually with a Guru-message beginning with 8 and ending with 4.
The Amiga has KS 3.1 and 2Mb chip RAM. That´s it.
Does it sound like a ROM-problem to you guys?!
Has anyone experienced the same?!
Btw, I have tried changing the 8520-chips and the Paula-chip with no luck.
Please help.... :-?
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A red flashing screen is usually the cause of a badly seated custom chip. On the A500 this was almost always the Agnus that needed to be reseated. Try reseating the Agnus chip it might be loose in the PLCC socket. Note the Agnus Chip is square , if you are very carefull and don't have a PLCC remover very carefully use a tiny Jewlers screwdriver to slightly lift the Chip at the 2 slotted edges. Do not apply much pressure, and then press the chip down again. If you can get the chip out check that all the contacts in the socket appear to be properly alligned.
Cheers
Shaf
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Yeah, what he said.
Try this site for some information.
http://www.scotek.demon.co.uk/guru.html (http://www.scotek.demon.co.uk/guru.html)
http://amiga.emugaming.com/guruguide.html (http://amiga.emugaming.com/guruguide.html)
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Nah, red screen on an A3000 is either a poorly seated ROM or it's a bad ROM. I think I have some A3000 ROMs here (none are 3.1) if you end up looking for one to try.
[If you decide to try the agnus... never ever ever try to leaver a plcc chip out of it's socket, you'll end up cracking the socket (and might not even notice) you're better off using some form of tool that is an L shape and simply hook it under one corner and pull straight up. Even if you bend a leg or two you can always straighten them out. It's not fun to have to replace the socket though.]
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What about fast mem? How much?
How did you get this machine?Did someone give it to you broken or sold it to you? Do they have any ideas on the problem and did they remove the zip chips(fast mem). Zip chips are somewhat in demand and could have been sold!
You say in your post 9 out of 10 times it guru's; well does it boot on that one time?
What is the whole guru error number?
Are you blessed with some Amiga knowledge? HAHA I meant have you owned a Amiga?
I think you could have something in that Amiga 3000 and could be worth fixin. Anything short of a bad soldered chip could be quite easy to correct. If you have a problem like I described above might be cheaper to buy a new mother board. Software hut is where I sent mine years ago and they did a awesome job on my mother board problem but I belive the much blessed Amiga Tech guy has gone and left software hut. I'm not sure if they even service Amiga anymore but you might want to give them a call.
:-D :-D
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First of all, yes, I have some Amiga experience.
I actually sell quite a few Amigas on Ebay every now and then, but they are all working... ;-)
This Amiga 3000 comes from a video store in Norway somewhere.
It came with a SIMMfonie SIMM-to-ZIP adapter, but this one broke in transport.
I can of course solder on the pins again, but I really don´t have the time..
The Amiga boots 1 out of 10 times. This time it will show the workbench-screen from f.ex. the OS3.1 Install disk.
It can stay like this for a long time, until I move the mouse or touch the keyboard.
It will then show Recoverable alert: # 07000004
After this it will reset with Guru alert: # 80000004
Then it will reboot again, and start with the red flashes.
Sometimes it will even show a ´suspend - reboot´ window while booting from Floppy;
Df0: failed
Suspend Reboot
It seems to me like this can be faulty ROMs, since it flashes red, but can it also be some kind of floppy-controller or another custom-chip?!
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Since, the simm/zip board is broken I take it you have no fast mem?
If you don't have memory the computer can't work correctly! Put some fast mem in ;zips,dips or simms. Leave the chip mem as is. I would also get some other roms and give them a try. Since, you have some Amiga knowledge and maybe the ability to get another A3000. You could swap some parts ram and roms to see if it works.Maybe, a friend could loan you a computer! :-o
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The machine has two megs of chip RAM.
I take it that it won´t function properly with no fast RAM?!
Btw,
I plugged in an old 030 CPU card from and A4000. This makes the machine boot to workbench.
It lets me open files and such, but as soon as I try to drag the whole screen it crashes.
Guess I will try some other ROMs and some memory and see if this helps.
Or just get me a used Amiga 3000 mobo from the last Amiga store in Norway...
I´ll let you guys know how it works out.
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I don't belive it will but you could move a meg back to the fast mem (dips) and see if that works. 1 meg chip and 1 meg fast might work.
I belive this is the way it is shipped and when you start adding zip memory in the fast mem banks the dips are moved to the chip mem area! Zips and dips do not work together in the fast mem banks ;its one or the other.You get a lot more memory in the zip banks I belive 12mb can be added to fast mem. I belive you can have up to 4mb in the dip banks.NOT BOTH!
Chip memory is for graphics and 2mb is the max. If you could get a hold of some memory I think you might be OK.
The OS you are using is 3.9 or 3.1 may need more memory?I would give it a go and move some memory around and see if you could get a good stable boot. :-?
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Tried it.
Didn´t work. Now it fails with memory mapping error or something.
I have decided to get a used Amiga 3000 off eBay or from the Amiga store over here in Norway.
Thanks for the help anyway... ;-)
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I did some research and you can put up to 16mb of fast mem on it. I would bet you will need at least 4mb of fast ram for 3.1 WB.
I hate to see you buy another if nothing is wrong with the one you have! No memory or low memory sounds like the problem.
Well, if you get another you can possible fix it and have a back up,also.
:-D
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It sounds like low RAM problems to me as well. Put 1 MB worth of the DIPS back in the Fast RAM side and see if an old game will boot. Should be the only trouble you have.
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Check your jumper settings on your motherboard. If you added a 030/25 and it was a original 030/16 you may have to set the jumpers for 25mhz and if it has an fpu you may have to set the jumpers correct for that too. I remember when I added a 040/25 ages ago I came up with a similar red/yellow flashing as you described.
Also if your able to boot at all and you actually have some fast memory in your 3000 and get to the workbench try running a program called SCRAMmer and do a ram check from the ram test section. And read the SCRAMmer guide lots of useful information in there about scram,zip,dip memory and the proper way to configure your ram.
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Thats right the first thing to check is that all jumpers are properly set. Ensure that no jumper is set to external if no accelerator is installed. Also check the 1 or 4 Meg jumper is properly set. I personally don't think lack of fastram is the problem, cause I almost certain I've run an A3000 without fastram.
As for the colors. These are what they usually mean
RED - ROM Checksum failure.
YELLOW - Daughter board not installed or bad.
The YELLOW stuff is a quite anoying part with the A3000. That all parts have to be assembled to have the Amiga running. A good idea when messing around in your A3000 is to dismount the drive bay from the powersupply. This way you will be able to reach the motherboard while still be able to power it on.
As for my knowledge of the 3000 series is that they can take quite alot. I've got an A3000T motherboard from a computer that looked like it had been run over by a truck. It had been shortened by about one feet and looked like a banana. There was only some small problems with it. One was that Fat Agnus fell out of it's socket if the motherboard was turned over. Second problem was that one of the PAL chips was not operating properly. Replacing the PAL chip and a socket fixed the board.
If you are unlucky it could be a PAL chip that has gone defect. They are programmable chips and are very sensitive and has sometimes the bad habit of just dying. If so you have to get a new chip and find someone with a PAL-programmer to program it. Or you just buy it from an Amiga dealer.