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Old 03 July 2014, 14:24   #168
pandy71
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Join Date: Jun 2010
Location: PL
Posts: 1,546
Quote:
Originally Posted by FrenchShark View Post
On AGA machines, the CPU has 32-bit access to Chip RAM (but still at 3.5 MHz).
But, Paula always does 16-bit access to Chip RAM for Audio and Disk DMAs.

Regards,
Frederic
AFAIR on A3000 CPU have 32 bit access to CHIP where chipset use 16 bit bus - bus conversion is performed by bunch of TTL's (mostly 74646) - later this was converted to LSI (Budgie on A1200 and Bridgette on A4000 - http://en.wikipedia.org/wiki/Amiga_c...hips#Bridgette ).
So in theory AGA can be connected to 16 bit CPU bus but seem that even greedy Commodore abandoned such idea (IMHO it was never even prototyped). I found note about potential possibility to have MC68000 and AGA - see http://www.amigawiki.org/doku.php?id=dearts:bridgette ",as well as 68000 based Amigas with AA chip set."

But knowledge that E clock is automatically recognized by Kickstart sounds nice - i need to check and double it - maybe 1MHz 8520 will be sufficient to work with 40% faster clock (especially after rising slightly 5V).
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