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- Date: Tue, 21 Jun 94 04:30:02 PDT
- From: Advanced Amateur Radio Networking Group <tcp-group@ucsd.edu>
- Errors-To: TCP-Group-Errors@UCSD.Edu
- Reply-To: TCP-Group@UCSD.Edu
- Precedence: Bulk
- Subject: TCP-Group Digest V94 #125
- To: tcp-group-digest
-
-
- TCP-Group Digest Tue, 21 Jun 94 Volume 94 : Issue 125
-
- Today's Topics:
- IP-TNC, the beginings? (2 msgs)
- Standard Digital Radio Interface
-
- 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 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: Mon, 20 Jun 1994 14:53:01 -0400 (EDT)
- From: DJ Gregor <dgregor@bronze.coil.com>
- Subject: IP-TNC, the beginings?
- To: nos-bbs@hydra.carleton.ca
-
- The type of IP-TNC (or PPP-TNC) that I would like to make right now is a EPROM
- that goes into your standard TAPR-2 clone. Most people that are running KISS
- are running on a TAPR-2 clone, and that is what I would like to have something
- better for *right now*. (oh, I wouldn't consider anything like what Barry
- suggested a Terminal Node Conroller, something like that should be called a
- packet switch.)
-
- I have been thinking about an IP-TNC for a while. When David Kelly, N4HHE
- suggested it on the nos-bbs list, I decided to start. I am in high-school and I
- am off for the summer, so I have _plenty_ of time to work on it.
-
- What I would like to start with is change the KISS interface to SLIP and put
- ARP in the TNC. Then, we can figure out something to do with AX.25 packets,
- either send them to the host on a UDP port, or maybe a Telnet session or some-
- thing like that. Eventually, I would like to have the TNC able to do routing;
- instead of having a node stack of NET/ROM TNCs, have a node stack of IP-TNC's.
- My goal is to have an IP-TNC that can connect to a host machine via SLIP or
- PPP. That is it--no AX.25 to mess with (leave that to the IP-TNC).
-
- I am thinking of using the wg7jkiss.asm code (found in /pub/ham/wg7j/kiss.zip
- on ftp.ece.orst.edu) which can be compiled with tasm276, found on
- oak.oakland.edu (or any of its mirrors) in /pub/msdos/crossasm/tasm276.zip.
- I figure that most people are using DOS, and those who run Linux, as I do, can
- use DOSEMU.
-
- Also, on the note of a packet switch, I think that a processor such as a 80x86
- would be a poor idea. There are better proccessors out there, and many of them
- have FREE assemblers and C compilers. Motorola makes a number of versions of
- their 68000 series. David Kelly suggested the MC68306. It has a 68EC000 core
- processor (which is a low-power version of the 68000), has a dual UART, and an
- onboard DRAM controller that can control up to 64 megabytes of memory. There
- are a number of FREE C compilers for this processor, including GNU C. Also,
- the Linux operating system has been ported to this series of processors, so
- that would provide a nice, pre-emptive multitasking kernel *WITH TCP/IP*!!
-
- If anyone is interested in working on an IP-TNC or an "Awesome Packet Switch",
- E-mail me. I would really like to get this going, and hopefully get a good,
- working version of an IP-TNC by the time summer is over. I will be away for a
- week on vacation, so don't expect to get a reply back real fast.
-
- -----
- DJ Gregor, N8QLB
- dgregor@bronze.coil.com
- "...oh, you use DOS, sorry to hear that..."
-
- ------------------------------
-
- Date: Tue, 21 Jun 1994 09:38:45 +0200 (BST)
- From: A.Cox@swansea.ac.uk (Alan Cox)
- Subject: IP-TNC, the beginings?
- To: dgregor@bronze.coil.com (DJ Gregor)
-
- > Also, on the note of a packet switch, I think that a processor such as a 80x86
- > would be a poor idea. There are better proccessors out there, and many of them
- > have FREE assemblers and C compilers. Motorola makes a number of versions of
- > their 68000 series. David Kelly suggested the MC68306. It has a 68EC000 core
- > processor (which is a low-power version of the 68000), has a dual UART, and an
- > onboard DRAM controller that can control up to 64 megabytes of memory. There
- > are a number of FREE C compilers for this processor, including GNU C. Also,
- > the Linux operating system has been ported to this series of processors, so
- > that would provide a nice, pre-emptive multitasking kernel *WITH TCP/IP*!!
-
- So why not just use a low power PC design. Its cheap and the parts are
- easy to get. There is a real danger of getting too carried away here.
-
- Alan
-
- ------------------------------
-
- Date: Sun, 19 Jun 1994 22:11:52 -0400
- From: goldstein@carafe.tay2.dec.com
- Subject: Standard Digital Radio Interface
- To: tcp-group@ucsd.edu
-
- I don't have EIA-530 and V.35 in front of me, but I can comment a little
- on these and some other options that already exist.
-
- RS-232C is very common, but only spec'd to 19.2 kbps. It is obsolete.
- RS-232D and I think EIA-232E (they no longer use "RS") are spec'd for
- higher speeds and longer distances, though I don't know the actual
- limits. Many devices implmeneted "232C" with longer range, but the
- new flavors actually make it supported, by tightening some specs.
- It's usable sync too, with a big DB25 connector; that's probably a bit
- larger than we want for the digital radio interface. Also, -232C is
- bipolar (+-15V) which is a bit tough to generate; I don't know -232E's
- voltages but it's also bipolar. My vote: No.
-
- RS-423 is a lot like -232, one-sided bipolar and even interoperable.
- RS-422 is differential, so it goes megabits. RS-449 spec's the connector
- but it's a big 37-pinner if I recall. Again, not quite right.
-
- V.35 is so popular that the CCITT actually DELETED it from their list
- of approved Recommendations! A truly conformant implementation of
- V.35-1984 is very difficult. A nonconformant but compatible implementation
- is fairly cheap. I think you need ECL or something to be exactly right.
- The connector is HUGE and grody. My vote, No. But I don't think it's
- necesssarily bad to build something V.35-compatible the way most folks
- do, using a smaller connector and cheaper electronics. I've seen many
- incompatible ways of wiring V.35 onto say DB25 connectors.
-
- EIA-530 is newer, and while I don't have a copy or know its details, I
- am led to believe that it uses the DB25 connector and is electrically
- interoperable with most V.35 and RS-422. This may be the best place to
- start, though we may want to specify a small-connector subset if that's
- adequate.
-
- BTW, I don't see this as a TCP-IP connector. It's for any digital
- radio applicatoin, be it TCP/IP, Vanilla AX.25, non-ham, etc. I think
- a modem/radio combo would be a nice thing to have, something like what
- Tekk does but most of the volume vendors don't, yet. Maybe we could
- encourage th em with somethng like this.
-
- There is the issue of "computer-controlled radio" too. Do we want the
- SAME connector to do things like change channels? (E.g., Yaesu CAT,
- etc.) I'm not convinced either way. V.25bis and X.21 both specify
- inband control with an out of band lead to tell whether hte message
- is data or control. These are for Sync, the Hayes in-band hack is
- not suitable. Again t his could be hard to standardize, since different
- radio vendors will want to go their own ways, so at best this can be
- only an option.
- fred k1io
-
- ------------------------------
-
- End of TCP-Group Digest V94 #125
- ******************************
-