40-pin DIP "MOS 8520A-1" package

AndyLandy

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Along with my A2000, I received a pair of MOS 8520A-1 chips, apparently ordered from CPC. I don't know what they're for, or what use they are, so I'm wondering what purpose would an Amigan have for ordering these? The A2000 is working happily, so I doubt they've been removed from it.
 
Re: 40-pin DIP "MOS 8520A-1" package

MOS (manufacturer) 8520A-1 is the real name/code for the chip otherwise known as CIA.

Here comes some pictures from the Amiga CIA:
ciapair_2.jpg
 
Re: 40-pin DIP "MOS 8520A-1" package

Those chips are delicate and prone to go to silicon heaven if you plug or unplug mouse, serial/parallel devices or some joysticks while the Amiga is on.

Keep them as spares, you never know when you'll desperately need one.
 
Re: 40-pin DIP "MOS 8520A-1" package

rkauer said:
Those chips are delicate and prone to go to silicon heaven if you plug or unplug mouse, serial/parallel devices or some joysticks while the Amiga is on.

Keep them as spares, you never know when you'll desperately need one.

Advice heeded, I'll put them away somewhere. :)
 
Re: 40-pin DIP "MOS 8520A-1" package

Faulty CIA chips are often exhibited with floppy drive malfunction, mouse and joystick issues, and I think keyboard input too. Often with the A500 and A2000, if the floppy drive wasn't working correctly but the drive itself was fine then a trick swapping the two CIA chips over to see if that fixed the problem would indicate they were to blame and needed replacing.

Are you sure the chips you have are not faulty ones that were replaced in the A2000 already?
 
Re: 40-pin DIP "MOS 8520A-1" package

Harrison said:
Are you sure the chips you have are not faulty ones that were replaced in the A2000 already?

The thought had crossed my mind. I guess I could swap them and find out. Not sure it's worth the bother though.
 
Re: 40-pin DIP "MOS 8520A-1" package

Is there any use in keeping faulty chips? Why would they include them if they were knackered?
 
Re: 40-pin DIP "MOS 8520A-1" package

I've had some very strange things included with Amiga's I've purchased in the past.

One of the strangest was a spare A500 keyboard, but none of the keys have anything on them. They are all completely blank. What is the point in that? And for that matter where did it come from?
 
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