O/S design & implementation - was Re: FPGA tricks - Re: using new technology on old machines

[ben]

On 6/16/2015 8:56 AM, Paul Koning wrote:
>
>> On Jun 16, 2015, at 2:49 AM, ben <bfranchuk at jetnet.ab.ca> wrote:
>>
>>> ...
>>>
>> Since the computer I designed is a *small* computer, 8 & 16 bit
>> operating systems is what I am looking at for ideas. This is a 18
>> bit cpu with the concept, byte access of memory needs true 18 bit
>> addressing and 16 bits is bit small for general 1970's data. Think
>> of it as a something like a 9 bit 6800 cpu.
>
> If you’re looking at 1960s designs, you should be fine even if the
> machine had wider words.  By the standards of that era, any modern
> computer (probably including the one in your microwave oven) is
> *large*.  For example, the THE OS memory footprint is about 16k words
> (48k bytes), and that includes not just what we think of as a kernel
> but also all the device drivers and a bunch of language support
> library code.  Other designs from that era are smaller still.

There is *NO* computer in my MICROWAVE!
I have the good kind! ( I need to fix the the defrost and half power
settings someday).  Timer dings when food is cooked.

> paul
16K words seems right, for that era as core was swapped in and
out to run system and program threads. Since TIME SHARING was the
big development feature of that era, I am ignoring most main frame
operating systems. Single user with small memory and disk I/O as
similar to the mid 1970's is my goal.
But this is all I have to say, as I want stick to real hardware on this
list.
Ben.