Sync serial bridging over Ethernet, was Re: [HECnet] Multi-floor household (DECnet) routing help needed

[Dave McGuire]

On 01/18/2013 01:14 AM, Ian McLaughlin wrote:
I'm not working on anything now - I just came up with the idea.

  I meant "do you design stuff with microcontrollers".

I did some Googling, and there seems to be commercial units, all around
$1K per end (async is much cheaper).

  Good heavens!

Microcontrollers and digital electronics is another one of my
hobbies.

  Excellent!   Same here, though I also do it professionally.

Async serial is simple for a microcontroller to handle.
I've never actually looked to see if there's any synchronous
libraries out there.

  I'd do it with an HDLC/SDLC-capable chip like a Z8530...offload as
much from the firmware as possible, leave those cycles for protocol
handling.   Unless you meant wrapping bare ?DLC frames in packets?

Wrapping the data in UDP is simple.   The HDLC layer could deal with
error detection/correction.

  Yes!

The problem is finding surplus time to embark on this.   Maybe a few
of us could collaborate on it?

  I have that problem as well, but I got really excited when you
mentioned it, because I am doing a lot of designs with Ethernet now.   I
have a "base" design, a "hardware macro" if you will, that I've recycled
several times.   It's a Philips..erm, NXP LPC2300-series ARM7 with an
on-chip Ethernet MAC, and all supporting hardware.   I typically run
FreeRTOS and uIP on them.

  Interfacing an ?DLC engine to that would be a cakewalk starting from
that base design as a head-start.   I have a few tubes of Z8530s in
PLCC-44 packages here.

                            -Dave

-- 
Dave McGuire, AK4HZ
New Kensington, PA