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Author Topic: MegAChip - A500 agnus question  (Read 4165 times)

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Offline alexh

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Re: MegAChip - A500 agnus question
« on: August 06, 2008, 01:46:29 PM »
I've never seen one for sale for many many months.

It seems a shame to butcher an A600 for a 2Mbyte Agnus but they are your best source but you will have to desolder it. I've been looking out for a cheap "spares or repair" one for ages.

I do not think you can use any other 2Mbyte PAL Agnus other than the 318069-10 (i.e. a 390544-01 may not work)

Unless your MegAChip is for a CDTV... you're better off buying an A500 plus, A600 or A1200 and selling whatever it is you've got.
 

Offline alexh

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Re: MegAChip - A500 agnus question
« Reply #1 on: August 06, 2008, 02:20:46 PM »
The 8375 390544-01 is also an 84-pin PLCC.

I think will work, but not correctly.

The Agnus is only a fraction of what makes an Amiga PAL or NTSC.
 

Offline alexh

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Re: MegAChip - A500 agnus question
« Reply #2 on: August 06, 2008, 04:33:21 PM »
@ arnljot
Pin 41 does not do the same thing on the 8375 as on the 8372. It is not an NTSC/PAL selector on the 8375 which is why there are both PAL and NTSC chips!!

@ Gilloo
Having both an NTSC Agnus and an ECS Denise does not make your Amiga NTSC! You have to change clock crystals, move jumpers etc. You're just asking for trouble.

@ arnljot
Hold out for a -10 PAL variant.
 

Offline alexh

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Re: MegAChip - A500 agnus question
« Reply #3 on: August 06, 2008, 06:06:25 PM »
I meant ECS... too many damn abbreviations
 

Offline alexh

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Re: MegAChip - A500 agnus question
« Reply #4 on: August 06, 2008, 10:59:49 PM »
Someone's been reading the Agnus page on BBoAH ;-)

FYI: Some of the information on that page is not 100% accurate, I tried to get it upto date but exact information is a bit sketchy
 

Offline alexh

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Re: MegAChip - A500 agnus question
« Reply #5 on: August 07, 2008, 12:56:31 PM »
Quote

arnljot wrote:
@Thread
Btw, service manuals? Where do we find such documents? :)

http://en.wikipedia.org/wiki/MOS_Technology_Agnus

Quote

arnljot wrote:
Also, which machine introduced the Agnus 8375 318069-10?

A600 PAL