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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: HolySamosa on October 30, 2014, 11:19:46 PM
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Recently scored an Amiga 1000 that externally and internally looks great. Super clean!
However, when I power it up I get the following behavior:
1 - Black screen for approx. 4 seconds
2 - White screen for 1/2 second w/ four (i think) flashes of the power LED
3 - goto 1
Any suggestions?
Thanks!
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try reseating your 68000 and also all IC's on the daughterboard
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If the A1000 have 256 kb front expansion, then make sure the fit is properly or remove at all and check the boot.
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Thanks for the suggestions, guys! I tried removing the RAM expansion with no effect.
Will try reseating the ICs this weekend.
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Thanks for the suggestions, guys! I tried removing the RAM expansion with no effect.
Will try reseating the ICs this weekend.
hope it works as I could swear I had the same black screen when I had upgraded my CPU to a 68010 & problem was it wasn't seated properly. After pulling it out & making sure all pins were properly seated she booted up fine.
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I've now reseated all of the ICs and the CPU. It looks like none of the ICs on the daughterboard are socketed, so I didn't remove it.
I also tested the voltages from the power supply and compared to those listed in the "A1000 Assembly Level Repair" document. Voltages were as expected (well, I did read ~12.1v and ~5.2v, but I assume this is within tolerances)
Same behavior. :-(
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Ok so now try removing the extra 256kb cart at the front of the A1000 & see what happens.
Few things:
- you're just booting the A1000 with no external SCSI side cars right ?
- are there any internal ram boards or timing fixes etc you can see on the MB?
- what version of MB ?
Please post a picture of your MB here (both top & bottom if possible)
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Thanks! Will do all of the above, but it will have to wait a week. The Amiga 1000 and several of my other vintage computers just went on display for the week at a retro-tech exhibit at our university library. :-)
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Okay, I'm back at it.
I tried swapping out for another set of CIA chips I had handy-- no luck, same behavior.
Also reseated the daughter board and again the ICs while I was at it.
The motherboard is REV A 327049-01.
There are no modifications that are obvious to me and no boards installed other than the 256k ram expansion. No sidecar.
I do have a working Amiga 2000 that I could perhaps borrow parts from for diagnostics.
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Here are images of my motherboard and daughterboard:
(http://i847.photobucket.com/albums/ab37/HolySamosa/0DDE937C-EE05-4ABC-B90C-37EC2BA50076-613-000000DE1AD1F0F8_zps9c50f7fa.jpg) (http://s847.photobucket.com/user/HolySamosa/media/0DDE937C-EE05-4ABC-B90C-37EC2BA50076-613-000000DE1AD1F0F8_zps9c50f7fa.jpg.html)
(http://i847.photobucket.com/albums/ab37/HolySamosa/F0C70CE9-5B0D-4646-913A-58342E2E84E1-613-000000DE217A6D1C_zpsd867c0d3.jpg) (http://s847.photobucket.com/user/HolySamosa/media/F0C70CE9-5B0D-4646-913A-58342E2E84E1-613-000000DE217A6D1C_zpsd867c0d3.jpg.html)
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Recently scored an Amiga 1000 that externally and internally looks great. Super clean!
However, when I power it up I get the following behavior:
1 - Black screen for approx. 4 seconds
2 - White screen for 1/2 second w/ four (i think) flashes of the power LED
3 - goto 1
Any suggestions?
Thanks!
just a shot in the dark,these are A500 led blink codes, but may apply here:
Amiga keyboards come with their own Flash ROM, timer and 64 bytes of memory. Source of error can be determined thanks to Caps Lock LED blinking:
- One blink – keyboard ROM check error
- Two blinks – keyboard RAM check error
- Three blinks – timer error
- Four blinks – two lines or control keys shorted
you mentioned 4 blinks, so if there is a keyboard connected,disconnect it and try.