[aprssig] DIGI_NED 0.3.5 for embedded systems

[Henk de Groot]

Annoucement
-----------

Available now: DIGI_NED 0.3.5 sources for use in embedded systems.

This is a stripped down version of DIGI_NED to make it easier te reuse the 
DIGI_NED digipeating core in an embedded device. It contains the complete 
functionional rule-based digipeater core like the full DIGI_NED has. All 
additional features, like messaging, sat-tracking, telemetry, wx, serial 
in-out etc are gone to make the code footprint small and targeted at the 
main task: rule-based digipeating.

The source also cleaned from platform dependent code, so it doesn't use 
the Linux AX.25 kernel support but instead I added a simple multiport KISS 
interface. It is fully functional under LINUX, but not anymore under DOS. 
Because the AX.25 kernel support is not used in this code it cleanly 
compiles and runs under Cygwin.

The core source code is only 68 kB. It was a bit of work to find all the 
unused support functions after deleting the additions, but I think there 
is not much redundant code left, if any.

The documentation with this version has been updated to reflect the 
functionality of this version and is packaged with the source. The source 
is of course covered by the GNU General Public License, like the full 
DIGI_NED also is.

The source has been posted to:

http://www.homepages.hetnet.nl/~pe1dnn

To use it in your embedded TNC design you must:

1: find a way to load the rule-file (changes to read_ini.c)
2: change mac_if.c to communicate with your hardware instead of the KISS
    code (you can then drop kiss.c and kiss.h).
3: if you want verbose output then rewrite functions "say" and "vsay".

It is still some work to make this work on an embedded system, but I think 
it is a lot easier to reuse this code than to use the full DIGI_NED code 
with all the additional features.

I hope this contribution will stimulate the creation of more powerfull 
TNC-digipeaters, so the network can be realy fixed...

APRS[tm] is a Trademark of Bob Bruninga,
his home page is at "http://web.usna.navy.mil/~bruninga/aprs.html"

Kind regards,

Henk.

P.S. the digi_ned.ini file is a stripped down version of the file from the 
full version, it has not been adjusted to the "new paradigm" yet.

P.P.S. I coded multiport KISS from specification, I have no way to test it 
:-). My only KISS capable device is my TH-D7E (on which it runs by the way)...