[vcf-midatlantic] Original Macintosh Architecture Questions

John Heritage john.heritage at gmail.com
Wed Jun 23 21:28:39 UTC 2021


Thanks.  I did read most of those links actually before I posted.  I
appreciated the simple explanations on sound here.

That last link explained how the CPU shared the memory but I'm curious what
changed specifically in the classic and/or allowed the ST to perform a bit
faster on same code (while the ST also shares the bus with shifter).

Thanks

On Wed, Jun 23, 2021, 4:56 PM Andrew Diller <dillera at gmail.com> wrote:

> A few things:
>
>
>
> http://mirror.informatimago.com/next/developer.apple.com/documentation/mac/Sound/Sound-2.html
>
> https://en.wikipedia.org/wiki/Macintosh_128K/512K_technical_details#Sound
>
> Later Macs:
> http://midibox.org/forums/topic/11239-macintosh-apple-sound-chip/
>
>
> As for speed, read the Speed & Video Section:
> https://lowendmac.com/2014/inside-the-original-macintosh/
>
> for a possible explanation.
>
> -andy
>
> On Jun 23, 2021, at 4:24 PM, John Heritage via vcf-midatlantic <
> vcf-midatlantic at lists.vcfed.org> wrote:
>
> Hey folks --
>
> Two items I'm curious about on the classic (and very original) Apple Macs..
>
> 1.  Mac (128kb ,512kb, etc) audio -- was there a custom or off the shelf
> sound chip for the audio on the original Mac?  and was it 1 channel / and
> was it a custom chip by Apple?  (how did it achieve speech synthesis in
> 1984)
>
> 2.  The Macintosh Classic released in 1990 "was about 25% faster than the
> original Macs".  This is in line with the Atari ST often being quoted as
> faster than a Mac when emulating a Mac via Magic Sac or similar.  What
> changed in the architecture to make the Mac Classic (or an ST in emulation)
> faster than the original Mac?  Was it faster memory that gave more
> availability for CPU usage?  were only certain instructions sped up or was
> everything faster?
>
> Thanks!
>
>
>


More information about the vcf-midatlantic mailing list