| |
PA2AGA > TCPDIG 04.09.96 09:55l 221 Lines 7476 Bytes #-10898 (0) @ EU
BID : TCP_96_177
Read: DG7DAH GUEST
Subj: TCP-Group Digest 96/177
Path: DB0AAB<DB0KCP<DB0ULM<DB0LX<DB0RBS<DB0SEL<DB0ZDF<DB0AIS<DB0NDK<DB0ACH<
DB0ACC<PI8DRS<PI8DAZ<PI8GCB<PI8MBQ<PI8VNW
Sent: 960904/0503Z @:PI8VNW.#ZH2.NLD.EU #:61412 [Hoek v Holland] FBB5.15c
From: PA2AGA@PI8VNW.#ZH2.NLD.EU
To : TCPDIG@EU
Received: from pa2aga by pi1hvh with SMTP
id AA16888 ; Wed, 04 Sep 96 03:54:18 UTC
Received: from pa2aga by pa2aga (NET/Mac 2.3.61/7.1) with SMTP
id AA00004071 ; Tue, 03 Sep 96 23:13:19 MET
Received: from pa2aga-10 by pa2aga with SMTP
id AA00004011 ; Tue, 03 Sep 96 23:00:22 MET
Received: from pa2aga-10 by pa2aga-10 (NET/Mac 2.3.61/7.1) with SMTP
id AA00005410 ; Tue, 03 Sep 96 23:00:16 MET
Date: Mon, 02 Sep 96 09:19:10 MET
Message-Id: <tcp_96_177>
From: pa2aga
To: tcp_broadcast@pa2aga-10
Subject: TCP-Group Digest 96/177
X-BBS-Msg-Type: B
TCP-Group Digest Sat, 31 Aug 96 Volume 96 : Issue 177
Today's Topics:
200 kbps
K5JB
PPP/SLIP in connected AX25?
Radio Links and AX.25 backoff (4 msgs)
unsubscribe
Send Replies or notes for publication to: <TCP-Group@UCSD.Edu>.
Subscription requests to <TCP-Group-REQUEST@UCSD.Edu>.
Problems you can't solve otherwise to brian@ucsd.edu.
Archives of past issues of the TCP-Group Digest are available
(by FTP only) from ftp.UCSD.Edu in directory "mailarchives".
We trust that readers are intelligent enough to realize that all text
herein consists of personal comments and does not represent the official
policies or positions of any party. Your mileage may vary. So there.
----------------------------------------------------------------------
Date: Fri, 30 Aug 1996 14:43:59 -0500
From: Steve Sampson <ssampson@oklahoma.net>
Subject: 200 kbps
Speaking of speed. Here's an interesting web page:
http://www.wcrb.com/FMDigital/NAB96.html
It concerns the use of direct digital in commercial FM.
---
Steve
mailto:ssampson@oklahoma.net
http://www.oklahoma.net/~ssampson
"How come no one labors on labor day?"
------------------------------
Date: Fri, 30 Aug 1996 08:11:06 -0500 (CDT)
From: System Administrator <root@disco.oklahoma.net>
Subject: K5JB
I got the news this morning, that a great Ham, a great friend,
Joe Buswell, K5JB, passed away yesterday. Joe had an active
interest in packet radio and digital modes since the RTTY days.
I know many of you have met him at Dayton, and would like to
know of his passing.
Steve
------------------------------
Date: Fri, 30 Aug 1996 15:12:51 +0100 (BST)
From: Alan Cox <alan@cymru.net>
Subject: PPP/SLIP in connected AX25?
> You do have to be careful in the implementation not to do silly things
> like hand the HDLC frames to the AX.25 layer one byte at a time so you
> end up with lots of AX.25 tinygrams.
You get nasty timing effects. I've done PPP over TCP tunnels and
they have similar properties to an AX.25 tunnel and don't work
well. Framing in UDP the same size as the PPP frame is far faster
------------------------------
Date: Fri, 30 Aug 1996 07:27:38 +0100 (BST)
From: Jonathan Naylor <g4klx@g4klx.demon.co.uk>
Subject: Radio Links and AX.25 backoff
On Thu, 29 Aug 1996, Steve Sampson wrote:
> Sounds like a nice half-duplex, low baud-rate solution, to 1980's
technology.
> At 200kbps it's a dinosaur. If it ain't DMA, I ain't interested :-)
I take it that we can look forward to the Steve Sampson 200kbps 23cms
full-duplex radio and modem soon, for less than $300 in an easy to
reproduce design ? I would forget the DMA side, just let me plug an
ethernet into it, much easier.
In the meantime I am more concerned in dealing with todays problems and
producing usable software, rather than *talking* about some theoretical
utopian packet radio future.
> ---
> Steve
> mailto:ssampson@othello.tinker.af.mil
> http://oklahoma.net/~ssampson
Jonathan
--
+----------------------------------+---------------------------------------+
| e-mail: jsn@cs.nott.ac.uk | Telephone: +44 (0) 973 695261 |
+----------------------------------+---------------------------------------+
| Author of Linux kernel AX.25, NET/ROM and Rose. |
+--------------------------------------------------------------------------+
------------------------------
Date: Fri, 30 Aug 1996 15:26:06 +0100 (BST)
From: Alan Cox <alan@cymru.net>
Subject: Radio Links and AX.25 backoff
> reproduce design ? I would forget the DMA side, just let me plug an
> ethernet into it, much easier.
PIO is fine. Since you need to get the data from main memory to cache
if you DMA it then for small packets its faster to PIO than do the
DMA set up on a PC, take the cache hits from the invalidates caused by
the DMA, then take the hits to copy the buffer
------------------------------
Date: Fri, 30 Aug 1996 13:16:26 -0500 (CDT)
From: ssampson@othello.tinker.af.mil (Steve Sampson)
Subject: Radio Links and AX.25 backoff
> I take it that we can look forward to the Steve Sampson 200kbps 23cms
> full-duplex radio and modem soon, for less than $300 in an easy to
> reproduce design ? I would forget the DMA side, just let me plug an
> ethernet into it, much easier.
Evidently my sense of humor is poor. What I was getting at, was that
the speeds above 9600 don't need all that hand-holding to make the
conversion to RF. This was in line with the 56k PI2/Gracilis discussion
before we all returned to 1200 reality and the serial protocols...
> In the meantime I am more concerned in dealing with todays problems and
> producing usable software, rather than *talking* about some theoretical
> utopian packet radio future.
I'm hoping the Part 97 rules will allow the use of chips designed for
unlicensed bands. Manufacturers could offer two models, 1w and 25w
RF modems.
---
Steve
mailto:ssampson@othello.tinker.af.mil
http://www.oklahoma.net/~ssampson
------------------------------
Date: Fri, 30 Aug 1996 23:03:14 -0700 (PDT)
From: Dennis Rosenauer <rosenave@octoblob.rfnet.sfu.ca>
Subject: Radio Links and AX.25 backoff
According to Alan Cox:
>
> > reproduce design ? I would forget the DMA side, just let me plug an
> > ethernet into it, much easier.
>
> PIO is fine. Since you need to get the data from main memory to cache
> if you DMA it then for small packets its faster to PIO than do the
> DMA set up on a PC, take the cache hits from the invalidates caused by
> the DMA, then take the hits to copy the buffer
>
I disagree. How am I expected to handle a T1 (1.544 Mbits/sec) with
programmed I/O, I get a byte every 5.2 microseconds!
I have to use DMA or shared memory on the card. I also need hardware
MAC address detection.
Has anyone given any thought to a suitable protocol for T1 and faster
speeds? AX.25 really doesn't cut it any more, we are going to have
to be able to look for callsigns or other MAC address in hardware.
Anyone have any suggestions?
Dennis.
--
Dennis Rosenauer VE7BPE | A computer running for 2 seconds
rosenave@octoblob.rfnet.sfu.ca (home) can make as many mistakes as 20
rosenaue@mpr.ca (work) | men working for 20 years.
------------------------------
Date: Fri, 30 Aug 1996 21:13:09 -0500
From: griggst@q.continuum.net (Tony Griggs)
Subject: unsubscribe
unsubscribe griggst@q.continuum.net
------------------------------
End of TCP-Group Digest V96 #177
******************************
You can send your message for this bulletin
to: tcp-group@pa2aga on .AMPR.ORG-net
or: tcpaga@pi8vnw.#zh2.nld.eu on BBS-net
------
NOT TO: pa2aga@pa2aga or pa2aga@pi8vnw.#zh2.nld.eu PLEASE!!
It will get posted automatically within a few days
Read previous mail | Read next mail
| |
