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View Poll Results: What Amigas do you currently have in your collection?
Amiga 500 51 49.51%
Amiga 500+ 9 8.74%
Amiga 600(HD) 12 11.65%
Amiga 1000 9 8.74%
Amiga 1200(HD) 36 34.95%
Amiga 1500 0 0%
Amiga 2000(HD) 18 17.48%
Amiga 2500(HD) 1 0.97%
Amiga 3000(T/UX) 4 3.88%
Amiga 4000(T) 7 6.80%
Amiga CDTV 2 1.94%
Amiga CD32 15 14.56%
Amiga Prototype (1000+/3000+/3500/Other) 0 0%
Amiga Compatible (Draco/Access/Minimig/Pegasos/MIST) 2 1.94%
AmigaOne (SE/XE/MicroA1) 2 1.94%
AmigaOne (500/X1000) 0 0%
Emulators - I don't have real Amigas anymore 20 19.42%
Emulators - I've never seen/owned a real Amiga, but wish I did! 3 2.91%
My Amigas are all original - no mods other than original expansion cards, accelerator cards, RAM cards, sidecars, floppies, and SCSI/IDE HDD's of the day. 14 13.59%
My Amigas feature modern-day modifications such as DVI/HDMI/IDE/SATA/USB/RAM/CPU/GOTEK and CF upgrades. 7 6.80%
I own a mix of original and modified Amigas. 18 17.48%
Multiple Choice Poll. Voters: 103. You may not vote on this poll

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Old 24th February 2017, 8:52 AM   #2041
power's Avatar
Join Date: Apr 2002
Location: brisbane
Posts: 47,965

Originally Posted by dalek View Post
Yeah bad luck on the RAM chips.

From memory my 1MB Rev 6 A500 that was modded for 1MB chip would reach the Kickstart screen as 512K chip with the expansion removed. As it would with the mod - so I wouldn't worry too much about the expansion not being there. It will also get to Kickstart with no FDD - but may take around a minute to time out before the insert disk image appears.

If you haven't already tried the Agnus reseat I'd do that - it's a pretty common failure case for stored A500/2000s. The contacts are prone to oxidisation.
I'm not sure how your expansion worked, however with mine the 512K is added as FAST so it's available for games that required it, however the additional switch allows you to turn it into CHIP which then drops you back to 512K FAST but a full 1MB CHIP.

The switch was installed at the time just because I could. I think I rarely used it and ran it as FAST most of the time.

I used the PAL and NTSC switch a few times as well.

My Agnus got a good reseat and clean, thankfully a member has offered a loaner of a KS to see if that's the issue but I do have my doubts and I think a nice clean board is in my future.

At least then I'd also have a bunch of other chips to test things with.

Side question for anyone with a sidecar - does a GVP with a later KS installed on it then boot that later KS when the drive is set to HDD? The seller of the one I bought said it has 2.04 on it. This is actually another reason I think my Amiga is dead some other way as the GVP didn't boot either. The Amiga wouldn't boot with the GVP installed on Game (which I assume disables the HDD but leaves the RAM present and uses the internal KS) or HDD which ignores the internal KS and boots from the drive?
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Old 24th February 2017, 9:42 AM   #2042
Join Date: Jun 2001
Location: Wollongong
Posts: 42

That expansion is only 512KB so you could only be switching between:
- 512KB Motherboard Chip only
- 512KB Motherboard Chip +512KB Trapdoor Chip = 1MB Chip
- 512KB Motherboard Chip +512KB Trapdoor Fast = 512KB Chip + 512KB Fast

Any more than 512KB in the trapdoor for a Rev 6 requires wires to Gary which it doesn't look like you have.

What I was suggesting is that even with the switch in place, you should get a KS screen in the first case (512KB Motherboard Chip), regardless of the switch position with the expansion is removed.

If it really is getting to a white screen then that means system tests are ok and it's waiting for boot media - could your floppy cable be round the wrong way?

Another thing that has caught me out before is the video output - if you are using the RGB, check the composite for a KS screen and vice versa.

Could you post a close up pic of where the switch wires are soldered?

If the other KS ROM shows the same issues you could burn a diagrom http://www.diagrom.com/ and see if you can get some more info.
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Old 24th February 2017, 10:11 AM   #2043
power's Avatar
Join Date: Apr 2002
Location: brisbane
Posts: 47,965

yeah I read that RAM allocation back and realised I'd said the wrong amount of CHIP.

I've tried the video on the mono port for testing and yeah no dice on mono comp either.

No mods to Gary, just the pal/ntsc and trapdoor.

the chip/fast is pretty messy, as I said I had a crack at it as a total newbie and made a bit of a mess and someone else sorted it for me (he had to do quite a bit of cleaning up as I had no experience, skills and the worst iron known to man . There is a big possibility that it's all gone wrong in there but due to how messy it is I don't want to start in on it, I'm not confident enough I just wouldn't make it worse.

I might grab my multi and test for continuity if the replacement KS doesn't do the job.

FDD is definitely in the right way, the cable as you can imagine is quite old and the shape is very moulded into it.

I read breifely about the diagrom thing and might even give it a go - looks very handy.

I was also pretty sure that no switch would mean that the switch is basically ignored, but was unsure as I'd always run the machine with the trapdoor installed.
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Old Yesterday, 7:25 AM   #2044
Join Date: Jun 2012
Posts: 438

Hey Mickatroid, a while ago you were trying to make an SVHS adaptor for your Amiga (or C64?) - i thought this might help:
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