[comp.sys.amiga.hardware] A3000 ROMs

kilian@cinnet.com (Kilian Jacob) (05/15/91)

A quick question:

I heard that the 32 bit ROM in the A3000 is slower than its SCRAM.
Is this true? If so, is it significantly slower? I'm just wondering whether
there is any point in using ROMs with the A3000 (when the 2.0 ROMs are finally
released.. :-))

-- /<ilian

-- 
Kilian Jacob - Cincinnati, Ohio - VOICE: (513)-489-1891
UUCP: kilian@cinnet.com or {uceng.uc.edu, ukma!spca6, uunet!sdrc}!cinnet!kilian

chucks@pnet51.orb.mn.org (Erik Funkenbusch) (05/17/91)

kilian@cinnet.com (Kilian Jacob) writes:
>
>A quick question:
>
>I heard that the 32 bit ROM in the A3000 is slower than its SCRAM.
>Is this true? If so, is it significantly slower? I'm just wondering whether
>there is any point in using ROMs with the A3000 (when the 2.0 ROMs are finally
>released.. :-))
>
>-- /<ilian
>
>-- 
>Kilian Jacob - Cincinnati, Ohio - VOICE: (513)-489-1891
>UUCP: kilian@cinnet.com or {uceng.uc.edu, ukma!spca6, uunet!sdrc}!cinnet!kilian


yes, ROM is slower than fast RAM.  however, there is STILL a great advantage
to ROM.  what that advantage is, is that there is NO danger of ROM being
overwritten by naughty programs.  you can still use SetCPU to copy the ROM to
RAM, and i think get the extra advantage  of having it MMU protected from
writes.  not only that, but it's faster than loading a rom image off disk.  if
you were to load the rom image off disk and then use setcpu to MMU protect it,
your wasting 1 meg of ram instead of 512k.

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