On Jun 26, 21:15, Hotze wrote:
> I LOVE that idea. Now, it'd need to be EPROM, especially nowadays with
bug
> fixes, a new version every other day of the week, etc. but still, it's a
way
> cool concept. Which computers did this?
Acorn's RISC PC has the OS (RISC OS 3.7) in ROM, about 4MB IIRC. The
original Archimedes range (1987) had RISC OS 2.0 in ROM (512K, IIRC).
Usually they're mask ROMs or OTPROMs. The OS is structured as a series of
about 80 relocatable modules, so if an upgrade is required, you load the
relevant replacement module into RAM, and the kernel changes the links that
point to it. Of course, changing the kernel module itself is a little more
tricky, but it can be done -- the first RISC OS 2 upgrades had instructions
on how to boot the system from a disk to load a new "utility module".
--
Pete Peter Turnbull
Dept. of Computer Science
University of York
Received on Sat Jun 27 1998 - 06:02:01 BST