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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Gavilan on August 13, 2014, 04:26:31 AM

Title: Amiga 2000 help
Post by: Gavilan on August 13, 2014, 04:26:31 AM
Hi! Just got an Amiga 2000 in very a good cosmetic state.

i was told by previous owner that the machine was working. I had no way of testing it until i got home. The machine has mouse and keyboard. no har ddrive, no extra cards. No battery, removed by previous owner, but no damage to the board as far as i can see.

Machine is PAL made in Germany. I hooked up to a multinorm TV (PAL M, PAL N and NTSC) using an RCA cable from composite of the back of the Amiga to video input on the TV.

Screen is completely black. Nothing happens. Nada. After a couple of seconds (more than 30), the lights on the floppy drive begins to work, but no spinning, no noise. again , nothing. I tried to boot puting WB disk inside the floppy. Nothing happens. again, black screen.

I reseated all chips that may gone out of socket during travelling to my house. Again, black screen, nothing happens.

Am i missing something here? Should i be able to see at least WB boot screen if i switch on the machine and wait a couple of seconds?

Do i need a modulator as a must to be able to use it on a tv or just pluggint it the way im doing it should be enough to get a picture?

Sorry for too many questions. Its been ages since i used an Amiga for the last time, and i never had a 2000 before.

Any tips/help, much appreciated

Kind Regards

Sebastian
Title: Re: Amiga 2000 help
Post by: SACC-guy on August 13, 2014, 05:49:38 AM
The composite signal on the back of the 2000 is black and white.
But with no hard drive, the system should show "Insert workbench floppy"
Check the rom, to see if there is any battery damage under it.
The acid will travel from the battery area to the cpu and rom areas...look for a greenish color on the pins.

Check if the floppy disk drive is connected correctly. led always on means data cable is backwards.
And maybe check if the monitor is working with another device???

m
Title: Re: Amiga 2000 help
Post by: curtis on August 13, 2014, 03:16:51 PM
May sound like a dumb idea, but also make sure the cpu and ROM are oriented correctly!

It's pretty easy to get them in wrong if you're not paying attention.

Ask me how I know...
Title: Re: Amiga 2000 help
Post by: carvedeye on August 13, 2014, 03:51:04 PM
Probably unlikely but you have change the channel on your TV to RCA?
Title: Re: Amiga 2000 help
Post by: Oldsmobile_Mike on August 13, 2014, 06:50:18 PM
Not that it should affect your current issue, but is this one of the very early German-model A2000's?  What mobo revision?
Title: Re: Amiga 2000 help
Post by: Ral-Clan on August 13, 2014, 07:28:44 PM
I think there is a jumper on the motherboard to set the A2000 for two floppies, or one.  Make sure it's set for one.

Oh, and is there any floppy drive installed at all?  If none, it may take a super long time to get to the insert disk screen (if ever).  Can't remember precisely.  If no floppy drive at all, try installing one (and make sure it is properly set up as DF0: not DF1: - cable twist). This is also a good idea just in case you have a bad floppy drive that is locking up the boot process.

Jumper J301: floppies have this ID circuitry on board, but as it's not an industry standard capability, it has to be implemented on the A2000 motherboard to save cost on internal drives. Leaving the jumper open prevents the Amiga from seeing the ID sequence.
Title: Re: Amiga 2000 help
Post by: DiskChris on August 16, 2014, 06:52:28 PM
I'd check the power supply...you said no spinning, no noise, does the power supply fan spin??
Title: Re: Amiga 2000 help
Post by: Gavilan on August 19, 2014, 04:16:57 PM
Hi!
Thanks a lot for all the replies guys.
Mistery solved: bad CPU. As soon as i took it away again and cleaned all contacts, machine worked.

i took it again the cpu and 4 pins broken. It seemes they were already soldered, at least i saw that. Now, time to finde a cpu replacement, maybe from one of my A500...

@Oldsmobile Mike: i will take pics tonight or tomorrow and post them here in the thread so you can check


Again, thanks a lot for the support

Regards

Sebastian
Title: Re: Amiga 2000 help
Post by: Oldsmobile_Mike on August 19, 2014, 06:09:42 PM
This website explains the differences:

http://www.amigahistory.co.uk/a2000.html

Might want to nail down exactly which model you have in case any further hardware-related issues come up!  ;)
Title: Re: Amiga 2000 help
Post by: Amiwest on August 19, 2014, 08:19:50 PM
Glad to hear you found the problem.
Your first post requested information.
http://www.sacc.org/index-a.html
I have a lot of links. In the top section - Motherboard revisions will also show most motherboard rev. including the 2000.
In menu choose 2000, gives links of things for the 2000.
Title: Re: Amiga 2000 help
Post by: Gavilan on August 20, 2014, 02:01:02 AM
Well, it seems i have a A2000B CR rev.4.5
Nothin out of the ordinary i presume.. :-)
Title: Re: Amiga 2000 help
Post by: Oldsmobile_Mike on August 20, 2014, 06:29:24 PM
Quote from: Gavilan;771255
Well, it seems i have a A2000B CR rev.4.5
Nothin out of the ordinary i presume.. :-)

Nope, Rev. 4.x is definitely a common board.  You might try to hunt down a Rev. 6.x board if you're feeling up to it, they fixed a lot of issues in the newer revisions.  ;)