Page 2 of 3

Re: Altair 8800 connect to the internet ¿?

PostPosted: December 29th, 2018, 6:23 pm
by mcleinn
I'm currently planning to connect my AltairClone to the Internet via i-telex, a telex-over-IP network, run by German telex enthusiasts.
https://www.i-telex.net/ (use Google Translate if necessary - they do have an English speaking forum on their site, too)

Example setups:
Image Image Image Image

i-telex is a modular system based on interface boards for various teletype standards (TW39, current loop, ED1000, V21 etc)
Available boards here: https://www.i-telex.net/hardware/

- One of the cards features a teletype-emulating RS232 interface, to which the Altair could be connected.
- If you want to control the Altair via teletype, simply connect the teletype to another interface card.
- The third interface card is connecting to your internet via an Ethernet plug.

This way, you should be able to
a) connect any (historical, modern) teletype to the Altair Clone without need for additional adapters.
You'd simply "call" the Altair using an internal telex connection
b) connect the teletype to internet services via telex-to-internet gateways
(a few gateways already exist in the network, for twitter, weather - others on board, such as text mail reception...)
More gateways could be programmed as PC/Microprocessor-based virtual teletypes via RS232, or directly on-board (Atmel)
Added services could be made available to all users in the network
c) connect your Altair to other Altairs ("AltairNet") by opening a telex conection via serial port
d) connect your teletype to other enthusiasts in various countries (if still a bit Germany-focussed, but also several users in US, UK, Spain etc.)
regardless of changing telephone standards and without connection fees

I'm still in the process of setup, but I'll let you know how it goes.

Re: Altair 8800 connect to the internet ¿?

PostPosted: December 31st, 2018, 11:36 am
by TronDD
TomXP411 wrote:You can also use a WiModem to connect to the Internet. The WiModem is a microcontroller with an RS-232 interface, and it's very useful on systems like the Altair Clone.


I went with something similar. Followed the instructions here:
https://subethasoftware.com/2018/02/28/ ... -firmware/

Wrote about my experience putting it together:
https://blog.kagu-tsuchi.com/articles/a ... _wifi.html

If you're willing to connect a few wires and flash the firmware yourself, it costs ~$20 to get on the internet.

Now I need find what networking software is available for the Altair. Currently trying my hand at writing my own.

Tim.

Re: Altair 8800 connect to the internet ¿?

PostPosted: February 26th, 2019, 2:51 pm
by kwiebe
I read this thread with interest...at one point I started browsing Amazon for serial devices and reading reviews. Started reading one review that really resonated then looked up to see the person's name:

TomXP411

LOL...small world!

Re: Altair 8800 connect to the internet ¿?

PostPosted: February 26th, 2019, 8:44 pm
by TomXP411
kwiebe wrote:I read this thread with interest...at one point I started browsing Amazon for serial devices and reading reviews. Started reading one review that really resonated then looked up to see the person's name:

TomXP411

LOL...small world!


I get around :)

I'm trying to remember what that would have been... I bought several USB RS232 interfaces when I got the Altair Clone last year... maybe it was one of those reviews.

Now I remember.... one of the USB RS232 interfaces I got had fixed nuts on the plug, so I could not attach the cable directly to the Altair Clone. That seemed crazy, and I remember writing a review specifically to complain about that problem.

Re: Altair 8800 connect to the internet ¿?

PostPosted: February 28th, 2019, 4:33 pm
by virtualaltair
Good work! The WiModem looks interesting. Here are some comments:

> Since the Altair is wired as a DCE device

Newer Altairs may have an 88-2SIO board. The 2SIO is not really DCE or DTE. It depends on the internal cable. A common MITS 2SIO cable has RX & TX DCE and the other pins DTE. Handshaking like CTS may be tied to 5V without a current limiting resistor. Check your board and cables before making assumptions.

> This makes it nearly 100% compatible with legacy terminal software.

Early CP/M terminal software used dumb 300 Baud a 1200 Bps modems that predated the Hayes "AT" Command Set. The software was updated for the PMMI and Hayes S100 smart modems. "Newer" CP/M communications programs had overlays for various IO chips and modems. The Altair was history by the time "AT" based overlays were written.

CP/M communications programs for the Altair Motorola 6850 UART and the Hayes "AT" command set would be a great project, however the project pieces may be hard to find. There may be some commercial programs that support "AT" commands.

Tom

Re: Altair 8800 connect to the internet ¿?

PostPosted: March 5th, 2019, 11:10 am
by kwiebe
The software I'm using on the Pi for this is called "ser2net". Not sure if it's the same software Synoptic refers to upthread, but thought I would document it here.

Works well.

-Ken

Re: Altair 8800 connect to the internet ¿?

PostPosted: March 7th, 2019, 3:57 pm
by Synoptic
kwiebe wrote:The software I'm using on the Pi for this is called "ser2net". Not sure if it's the same software Synoptic refers to upthread, but thought I would document it here.

Works well.

-Ken

I use ser2sock

Re: Altair 8800 connect to the internet ¿?

PostPosted: March 7th, 2019, 11:40 pm
by virtualaltair
I'll look into "set2net" to add to my toolset, but my real interest is both client and server software that runs on the Altair. I use TeraTerm & RealTerm on Windows as File Transfer and Terminal programs for communication with my Altair & Altair clone. Windows software from Tactical Software connect Virtual PC COM ports to my GW312 server. The connection can be Telnet or RS-232 handshaking depending on GW312 configuration.

Mike & I have configured old CP/M communications programs BYE, XMODEM, and modified mini-RBBS to work on an Altair or clone connected RS-232 to a GW312. We have early CP/M programs that do not use smart modems or understand the "AT" Command Set. The BYE program does need RS-232 CTS. A PC program can operate a remote Altair CP/M console from a Windows PC.

Mike and I also set up Modem 2.21. This early CP/M program is a command line terminal and file transfer program that allows a Altair with a GW312 to operate and transfer files with another Altair. Modem 2.21 in a bit primitive and newer CP/M Terminal programs like the MDM7xx series are better. I'm still not sure if there is "AT" command support. Id start checking with CP/M MDM74x overlay versions or newer code.

My point is that Windows or Arduino to Altair communication is not the same as communication in the early Altair days. The newest CP/M communication software might work well with the WiModem. The work to save the newer CP/M software for use on the clone has not been done. Mex & ZMODEM protocol software are good places to start. It takes work to find all the old ASM pieces and modify them for the Motorola 6850 & ALtair addresses.

Re: Altair 8800 connect to the internet ¿?

PostPosted: March 8th, 2019, 12:07 pm
by kwiebe
virtualaltair wrote:I'll look into "set2net" to add to my toolset, but my real interest is both client and server software that runs on the Altair. I use TeraTerm & RealTerm on Windows as File Transfer and Terminal programs for communication with my Altair & Altair clone. Windows software from Tactical Software connect Virtual PC COM ports to my GW312 server. The connection can be Telnet or RS-232 handshaking depending on GW312 configuration.

Mike & I have configured old CP/M communications programs BYE, XMODEM, and modified mini-RBBS to work on an Altair or clone connected RS-232 to a GW312. We have early CP/M programs that do not use smart modems or understand the "AT" Command Set. The BYE program does need RS-232 CTS. A PC program can operate a remote Altair CP/M console from a Windows PC.

Mike and I also set up Modem 2.21. This early CP/M program is a command line terminal and file transfer program that allows a Altair with a GW312 to operate and transfer files with another Altair. Modem 2.21 in a bit primitive and newer CP/M Terminal programs like the MDM7xx series are better. I'm still not sure if there is "AT" command support. Id start checking with CP/M MDM74x overlay versions or newer code.

My point is that Windows or Arduino to Altair communication is not the same as communication in the early Altair days. The newest CP/M communication software might work well with the WiModem. The work to save the newer CP/M software for use on the clone has not been done. Mex & ZMODEM protocol software are good places to start. It takes work to find all the old ASM pieces and modify them for the Motorola 6850 & ALtair addresses.


Thanks for contrasting different Altair communication modes and some of the history involved. I appreciate the perspective your post provided.

Re: Altair 8800 connect to the internet ¿?

PostPosted: March 11th, 2019, 4:21 am
by virtualaltair
Thanks for finding the WiModem. I think it would be useful in saving old CP/M Terminal software. A Terminal Program could issue "AT" commands under operator control. This would allow a Telnet connection to more than one address. A modem overlay in the MDM74x format would be a starting place. The "newest" CP/M communications programs could be assembled after research into source code archives.

We have Remote CP/M operation with an IP address, but lack a menu driven Terminal/Transfer program than can "Dial" more than one IP address.

We have Altair Remote CP/M software that can do XMODEM and Kermit file transfers with WIndows Terminal clients. We do not have Altair software that supports ZMODEM protocol or the "AT" commands.

Users connect to my Altair clone over the internet. I not sure any "callers" are using an Altair or an Altair clone. More work to do to preserve CP/M history and update source old code to provide Altair M6850 UART support.