[En-Nut-Discussion] Nut/Os port to C166/ST10 family?

[Dave Smart]

Has anyone looked at porting Nut/Os to the 16-bit C166/ST10 family of
processors?

Here's just a few points I've pondered -

* Compiler
I use the Tasking/Altium compiler, and have no experience with alternates. I
haven't succeeded in freely acquiring a gnu/free compiler.

* Hardware and separate user stack 
It should be fairly easy to swap context. System stack has a size limit as
does the user stack space (w/o extra code/cycles to manage them), but is the
size really much of a constraint?

* Performance 
These parts scale to about 64 MHz and are still climbing, but I don't know
how their throughput actually compares to some of the ARM ports.

* I/O
As microcontrollers, these parts have a lot of I/O in a reasonably small
space, and are quite popular in automotive/industrial environment.

* Selfishness
I've executed quite a few designs in this family of processors, so I'm
familiar with them and have a lot software that uses their I/O. Switching
CPU architectures feels like it is at about the same scale as porting Nut/Os
to this architecture.

* Microcontroller
The ST10 can be had with over 1/2 M of Flash and over 64 K RAM, saving most
of the I/O pins for I/O.

* Life-cycle
We might think of these parts as "long in the tooth", but the vendors seem
to continue to evolve them and come out with newer parts in this family. 

* Ethernet
Sadly, I don't know of any variations with Ethernet onboard, so something
external would be needed. [SPI interface to avoid taking a bunch if I/O
lines?]



All the code I've written for these parts has been C. While I have looked at
the assembly (more so with the early versions of the compilers ;), I
wouldn't say I'm familiar enough to take on this port by myself, so I'm
looking to see if others are interested - and ahead or behind in my
thinking.

I look forward to your comments - 

Regards,
Dave Smart