PC Memory maps (was: Re: 486 w/newer IDE drives)

[Chuck Guzis]

On 24 Nov 2006 at 14:07, Sean Conner wrote:

>   The major problem with that is MS-DOS---it can't handle non-contiguous RAM
> and therefore there is no standard way to reserve or use memory in the upper
> 384K of the address space (well, for those PClones that followed the IBM
> spec).  

I seem to recall a few PCs with built-in CGA display adapters gave 
one more contiguous memory than 640K by filling the space between 
A000 and C000 with RAM.  And many "not very compatible" PCs running 
MS-DOS made the entire 1MB available.

Anyone with an old Visual Commuter want to verify this?  I think that 
the Commuter was one of the aforementioned.

Cheers,
Chuck