[time-nuts] An embedded NTP server

[Poul-Henning Kamp]

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In message <CAHjG12QXpb9PX8Dp6NgK-x575ETNSfC+csQr6ACSrX7gfW-gvA at mail.gmail.com>
, Tom Harris writes:
>+1 for Forth!

Indeed, but for me that is only an indulgence :-)

>+1 for your opinions on PICs & AVRs. We can buy low end NXP ARM Cortex M0
>chips (e.g. LPC1113) for less than the PIC18 we were using before, and it
>has a real compiler and (unlike the real world) evidence of intelligent
>design!

ARM is a very intelligent design, unfortunately it is falling prey to the
curse that hits any successful CPU: more and more complicated instructions
gets added "to help this one important case..."

This curse already claimed IBM's mainframe CPU and x86 cpus, and with the
"thumb2" set, ARM is caving too.

But it is a damn good CPU still.

>Do you really need an OS? Surely for a box that is only ever going to be an
>NTP server you just need a network interface and good maths? I've just seen
>a later comment where you mention floating point support, but would 64 bit
>integer maths work just as well?

Depends how much code you want to write yourself.  The advantage of having
an OS, is that somebody else maintains a lot of the code for you and you
get features like TCP/IP and SSH for free.

The disadvantage is that you need more flash to hold all that junk.

In general, you should reuse as much code as you can, life is too short
to write another UDP checksum subroutine.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.