🚀 go-pugleaf

In article <8652@cbmvax.UUCP> daveh@cbmvax.UUCP (Dave Haynie) writes:

> With fast memory and DMA, you only need one cycle to chip memory, at
> worst, to get unrestricted access to fast memory at full bus speeds.
> With CPU driven I/O, you'll need a few cycles, since interrupt
                                                 ^^^^^^^^^^^^^^^
> vectors are currently stored in chip memory, but it's not that bad.
  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> Some devices may not work at acceptible rates with hires 4 plane
> overscan screens if you only have chip memory.  With a little fast
> memory, there's not a big problem.	

This has always irked me.  When AmigaDOS added official support for
the 680x0 (where x<>0) chips, I was surprised that they didn't move
the interrupt vectors to fast memory (since the 68010 and up can do
that).

Chip memory is prone to trashing by errant programs (blitter-tricks
gone bad, beginning programmer mistakes, etc.)  Might this be a
feature of 1.4?  It could be a switch in preferences to keep older
working.

> Dave Haynie Commodore-Amiga (Systems Engineering) "The Crew That Never Rests"
-- 
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