Subject: Re: Sun 3/50 Ham Radio.
To: None <hth@update.uu.se>
From: David Kelly <dkelly@hiwaay.net>
List: port-sun3
Date: 02/06/2001 18:56:00
"=?ISO-8859-1?Q?H=E5kan Th=F6rngren?=" writes:
> >>>>> "David" == David Kelly <dkelly@hiwaay.net> writes:
[...]
> I used a TNC in KISS mode.  The big problem with it was that there
> were no feedback of when a packet was sent.  I guess the only way
> around it would be to have some kind of measuring of the amount of
> data sent down to the TNC and brutally throw excess packets away
> without trying to send them..  TCP should be able to adopt to it, I
> think (and hope).. 

There exists "enhanced KISS" firmware which is able to checksum the 
packet from the host, and inform the host when a packet clears the TNC. 
On a busy mountaintop it may be minutes before the TNC hears an opening 
to try inserting your packet into.

Some enhanced KISS firmware I've heard of is able to run multi-drop. 
You burn an address into the EPROM then you can build a serial network 
of TNC's all on the same host serial port. Such a messy network 
explains the need to checksum the serial cable.

Different manufacturers offered "host" modes which allowed various 
capabilities. None were very good at providing a protocol mode for 
controlling the TNC automatically. "Multi-connect" TNC protocol was 
impossible to automate and keep track of what data came from where. So 
"terminal" program authors found it easier to run the TNC in the raw 
(KISS) and do the protocol themselves.
 
> David> IMHO what is needed is a Unix-like ability to build unique applications
> David> on a solid base. Am not referring to *BSD but to the Unix Way where you
> David> build a good solid engine where fairings and trailer hitches can be
> David> added by others without breaking everything. Such as the way a Unix
> David> shell integrates all the other utilities.
> 
> You mean doing it the opposite of the PC world.  I remeber once when a
> guy talked about bsome specific backup software for PC (DOS) that was
> to connect to a SCSI tape, but the backup software "unfortunately did
> not include the proper driver for the SCSI card he had".  
> I was puzzled (being a non-PC person) and asked him why the driver was
> not included with the SCSI card.  Well after some explanation I
> realized the MS-DOS should be outlawed forever and that I would never
> want to touch it, ever...
> After having tried NOS my conclusion was throw it away and do it the
> right way, which I did for the AX25 part on the Amiga.

I remember a DOS "guru" frightened when I started laying out before him
all the things he had to take care of to write code for an embedded CPU.
Then I pointed out DOS was nothing but an embedded program loader and to
do a good job he had to do all these things in his DOS programs. Then
the light bulb came on and he felt right at home.


--
David Kelly N4HHE, dkelly@hiwaay.net
=====================================================================
The human mind ordinarily operates at only ten percent of its
capacity -- the rest is overhead for the operating system.