OT: OS for 186 computer

[Roger Gt]

X-No-Archive: yes
"Rich Grise" wrote
: "Sergey Kubushin" wrote
: > Rich Grise wrote
: > > off; at least I haven't heard of them much lately. I worked
with
: > > a 186 once, and it took ordinary 8086 code. Since Linux is
written
: > > in C, I can't think of a reason why it couldn't be done,
although
: > > preemptive multi-tasking might be a little hairy. =:-O
: >
: > It lacks MMU. But there is a Linux flavor for MMU-less CPUs
out there )
: > Its called ucLinux.
:
: What's "MMU," and how would that impact running Linux?

"Memory Management Unit" without which the address range is
severely limited and multiple users / threads must manage their
own data address space (among other things.)

 

[Tim Hubberstey]

Rich Grise wrote:

"Sergey Kubushin" <ksi@koi8.net> wrote in message
It lacks MMU. But there is a Linux flavour for MMU-less CPUs out there )
Its called ucLinux.

What's "MMU," and how would that impact running Linux?

An MMU is a Memory Management Unit and it is a necessary part of a
virtual memory architecture. It is used to dynamically map portions of
the processor's address space onto portions of available physical memory
(pages). Linux (and most other modern general-purpose OSes) use MMUs for
two purposes:

- to provide a "virtual machine" to the process so that, as far as the
process is concerned, it has memory available throughout the entire
memory space

- to make it appear to a process that it has more memory available than
the available physical memory by using hard disk swapping

For more info, and probably better explanations, search for "page fault"
and/or "virtual memory".
--
Tim Hubberstey, P.Eng. . . . . . Hardware/Software Consulting Engineer
Marmot Engineering . . . . . . . VHDL, ASICs, FPGAs, embedded systems
Vancouver, BC, Canada . . . . . . . . . . . http://www.marmot-eng.com