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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: SEgamer on November 21, 2011, 02:45:06 PM

Title: A1000 boots to blinking red screen
Post by: SEgamer on November 21, 2011, 02:45:06 PM

I recently got an A1000 that has some issues. I'm new to amiga stuff and trying to educate myself on it, so please correct me if I'm wrong.
 
The problem:
The system immediately boots to a blinking red screen. There is no response from the floppy drive when a floppy is in it.(I had to point that out because on another site people kept saying to insert a kickstart floppy). There's no grey screen at all before that. If I remember correctly there's different grey screens, one for each major component, that are displayed during the boot sequence correct?
 
I looked up the error colors and red appears to be a bad checksum from the boot roms. I'm just wondering if anyone else has had this problem and trying to confirm that it is the roms.
 
My other question is that should the screen blink or should it stay red? I'm wondering if another chip is causing a timing error and/or other things to reset. I pulled and re-seated every socketed chip and checked the voltages on the psu, but still have the same results.

Title: Re: A1000 boots to blinking red screen
Post by: spirantho on November 21, 2011, 03:27:43 PM

Does your A1000 have a Kickstart ROM or just the bootstrap? In other words, if you boot it without a disk, does it come up prompting for a Workbench disk or a Kickstart disk?

Title: Re: A1000 boots to blinking red screen
Post by: SEgamer on November 21, 2011, 05:17:57 PM

It only has the bootstrap ROMs. I get the same results with and without a floppy in the drive.

Title: Re: A1000 boots to blinking red screen
Post by: Oldsmobile_Mike on November 21, 2011, 07:04:38 PM

Bad floppy drive, not trying to read the Kickstart disk maybe?

Title: Re: A1000 boots to blinking red screen
Post by: motrucker on November 21, 2011, 08:57:56 PM

I have seen this happen when an upgrade card that required a special (replacement) PAL chip was removed, but the pal chip was left in. Is that possible in this case? Do you know any of the machine's history?

Title: Re: A1000 boots to blinking red screen
Post by: SEgamer on November 22, 2011, 12:07:38 PM

Quote from: Oldsmobile_Mike;668602

Bad floppy drive, not trying to read the Kickstart disk maybe?

I'm about 90% certain that it's not the drive because the screen asking for a kickstart disk is never shown. I think the screen should show up even without a floppy drive hooked up to it, though I could be wrong.
 

Quote from: motrucker;668618

I have seen this happen when an upgrade card that required a special (replacement) PAL chip was removed, but the pal chip was left in. Is that possible in this case? Do you know any of the machine's history?

Unfortunately I don't have any info on it. It came from a guy who's grandfather owned a computer repair shop from the 80's to mid 90's. The chips and other components appear to be original.
 
I guess my best bet is to get a working board or all of the ICs from a working A1000 and swap stuff out until I find the culprit. I think he had an extra A500 I might be able to use if they're similar.