Amiga.org
Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: foleyjo on May 05, 2006, 09:13:05 PM
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last night I opened up my A500 to see if I could work out why it has stopped working (cant get a picture tried the modulator on another amiga and it works fine)
I was surprised to find a couple of items in there Ive never seen before.
Firstly this might be me being ignorant/stupid but I noticed a big Paula chip. I thought they were only found in later amigas like the 1200/4000
Secondly where the rom chip is supposed to be was a device which claims to be a keyboard rom switcher. Am I right in thinking this lets me use 2.0 or 1.3 kickstarts? How does it work?? and where the hell do I put it? The switch part of it was just flopping about inside. (might be part of the main problem)
The last thing I found was a strange rectangular block which appears to be soldered onto the motherboard near the expansion board slot. If anyone knows what type of thing it could be I could go have a look and see if its the same
Sadly I cant take a picture of these parts as my camera isnt working at the moment
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Paula is standard on every Amiga. Nothing to worry about there.
Your next item is a kickstart switcher, and yes, it will let you switch between 1.3 and 2.0+. Most of them work by holding down a key during a reboot and acheive this functionality by running a flying lead to somewhere else in the system. Yours seems to have come loose. Check http://www.amiga-hardware.com to find which switcher you have. Hopefully it'll tell you where to connect the lead.
The last thing could be the 68000 itself, or some sort of accelerator with a 68000 soldered to it. Again, check the BBoAHW for anything like it.
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Strange things are afoot in my a500
that's it, has start the invasion from Mars :lol:
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Cheers. Ive found what appears to be the kickstart switcher and it also explains the other device.
I believe it to be a Switch-Itt. It looks a lot like the Wilcom which according to the BBAH is the same design. It goes on to say
"The SWITCH-Itt draws power from a clip that attaches to pin 18 of the 68000 CPU."
Another mystery solved with the help of the kind folk at amiga.org :-D
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Glad to help.
So what was the other device? I'm curious now... :-)
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@foleyjo:
Those bobs over at amiga-hardware got those facts about the power wrong. Pin 18 of the 68000 cpu is the reset pin and the kickstart switch uses it to detect when you reset your Amiga (it switches kickstart when you hold reset for about 4 seconds).
/Patrik
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Makes a lot more sense - power's available everywhere. Better tell Ian about it, to correct BBoAH.
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The other device was the thing the romswitcher draws power from