piclist 2000\05\30\030357a >
Thread: Embedded Internet enabling methods: Which?
www.piclist.com/techref/index.htm?key=which
face picon face BY : William Chops Westfield email (remove spam text)



   I just wish there was a free full TCP/IP implementation out there for
   the PIC :)  I dread having to write my own.

   I've looked at the previously mentioned implementations, not with too
   much detail but they seem to have certain problems.. such as you
   mentioned.. hardware based or limited features. I want an API library
   where I can use standard library calls like in unix to program my
   application.
   I don't want to only be able to use certain ports, or have to connect
   via a ppp/slip link.. Let me know if you find anything like this..

IMO (not very humble - I've got a fair amount of experience in this area),
this isn't possible.  To start with, the protocols pretty much assume an
environment with "separate" operating system and applications, which will
get you to pretty large code (for the "OS" side, which has to have
"everything") pretty quick.  Implementing Internet connectivity on a small
microcontroller means cheating.  How badly you cheat, and where, and whether
you'll be able to get away with it on a large scale, is dependent on how
much space you're willing to sacrifice to the network code (and it IS
primarilly a space issue, rather than a speed issue.)

Possible approaches with "minimal" cheating:

1) Code-generator type scheme, where your code is carefully analyzed,
  and a "custom Network OS" is generated that implements ONLY those parts
  of the stack that you actually use.

2) an interpretter (basic-stamp-like, I guess) with a very large external
  memory... (here, performance might start to be an issue, of course.  An
  interpretted OS with applications written in assembly.  Weird.)

As a reference or starting point, you might consider NCSA telnet, an "open
source" (but predating that term) application/OS/Internet stack that runs on
DOS.  a 1990 ("pre-bloat but post-64k-frugal") implementation has a
"minitel.exe" program without too much extra stuff (like tektronix terminal
emulators) and is about 93kbytes (for the exe file.)  Other possibilities
include "ka9q" - a similar project targetted (restricted?) to ham radio
applications.

BillW

<CMM.0.90.4.959670198.billw@flipper>

In reply to: Your message of Mon, 29 May 2000 19:44:04 +0530
See also: www.piclist.com/techref/index.htm?key=which
Reply You must be a member of the piclist mailing list (not only a www.piclist.com member) to post to the piclist. This form requires JavaScript and a browser/email client that can handle form mailto: posts.
Subject (change) Embedded Internet enabling methods: Which?

month overview.

new search...