Re: Plus/4 C16 Questions

From: Richard Atkinson (
Date: 2000-02-24 01:15:50

On Wed, 23 Feb 2000, Levente Hársfalvi wrote:

> There is no difference between the C16 and Plus/4 ROM. Instead, the
> Reset routine checks the available RAM amount by the method Marko wrote
> (writes to $ffx0...$ffff, then checks if $3fx0, then $7fx0 is the same).
> Actually, it can detect three different memory sizes (16K, 32K and 64K)
> - there was a prototype in this series, the 232 which was somehow
> equipped with 32K of RAM.

It uses 4 41416 DRAMs (2 banks of 16K) which may be selected with NAND
gates, the normal RAS and CAS signals and A14 perhaps? (I'm guessing)

Does anyone on the list have a 232? Apparently they leaked out in the


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