14 Feb
2014
14 Feb
'14
12:28 p.m.
On 02/14/2014 12:02 PM, Peter Corlett wrote:
To get back on topic for this list :) the
segment-limit approach used in older
architectures such as the PDP-11 serve much the same purpose and can also be
considered a kind of bank-switching. Paging is just a lot more flexible and
segmentation is now obsolete.
There were also 8-bit systems that used a bipolar RAM to expand the
address space, as well as the old TI 74LS61x-series "memory mappers".
Page simply refers to the granularity of the switching mechanism. A
size of 512 bytes is convenient as it matches the sector size of many
disks, but I've used systems with much larger page sizes.
--Chuck