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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: kirk_m on May 28, 2017, 07:42:44 PM

Title: NTSC A500 question
Post by: kirk_m on May 28, 2017, 07:42:44 PM

If I place a PAL Agnus 8375 (318069-10) into my NTSC A500 (512 fast, 512 chip, ECS Denise, kickstart switcher between 1.3 and 3.1, Rev 6A motherboard), will it convert the machine into a PAL machine?

Thanks!

Kirk

The chip in question:
(http://i.ebayimg.com/images/g/JkwAAOSw0hlZIdZB/s-l500.jpg)

Title: Re: NTSC A500 question
Post by: Castellen on May 28, 2017, 08:51:59 PM

No, the 318069-10 variant (as used in A500+) has a different pinout, making it incompatible with A500/A2000.

You can instead use the 8272A Agnus (NTSC/PAL selectable via JP4 - open for PAL, 1MB).

Or you can use the 318069-16 variant of the 8375, which has a mostly compatible pinout with the A500, but you need to perform this modification (http://www.amigawiki.de/lib/exe/fetch.php?media=de:parts:agnus_reworks.pdf).  J102 as referenced in that document is JP4 in the A500, and there is no R101 to remove in the A500.


And you need to replace the 28.636MHz oscillator module with 28.375MHz.