ncoplin_at_orbeng.com
Date: 2002-05-02 08:19:55
>|Memory accesses (at least selected ones) need also go to the original
>|address/data bus elsewise the VIC chip will not see anything to display?
>program it in the MMU for which pages this applies (Note that on the C-64,
>the bus bandwidth to memory is only 1 MB/s!! Fortunately, this is a lot
But why limit ourselves to this? 1MB/s applies to most I/O chips on the C64
Bus and to boards with 300ns access RAMs, 300ns also for the 2114 colour
RAM. The 4164 DRAMs can readily be replaced with 100ns 41256s, thus with
perhaps a jumper (for enable /disable, or config register/poke) you should
be able to squeaze several writes in the valid 500ns ==> 2MB/s, 3MB/s or
4MB/s.
- Nick
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