libretro-atari800/atari800/DOC/r_device.txt

---- about the R: device in Atari800 emulator ----

From: Chris Martin <cmartin@ti.com>

I have some code that I have integrated into my personal
download of atari800 v1.3.0 for allowing talking to the
Atari800 emulator via R: and network sockets.  I have taken
some code released by Tom Hunt and made some bug fixes and a
few minor updates. 

I have tested this both under Solaris and Linux.  I have
plans to update the code to allow connections to the host
machine serial ports for talking to a real Modem as well.

I have tested this with Bobterm and Ice-T.  If you need the ATR files for
these programs, let me know.

Once in Bobterm or Ice-T you can type 'ATDI localhost 23', to telnet.

I would like to add options for allowing to compile this or not, and
command line args for the connect string and the port number (it accepts
connections on port 9000 now for in coming calls...)

Best regards,
Chris

===

The basic use of the R: emulation is that it emulates an Atari 850.  If
you use the bobterm.atr or the icet.atr disk image to run these terminal
programs, you can telnet to any telnetable Atari BBS in the terminal
screen by typing:

ATDL
ATDI <address> <port>


So, basically these two commands have been added on top of the 850
emulation.  The ATDL toggles Line feeds on/off.  the ATDI allow you to
telnet out to an atari machine.

For example, to telnet to my atari BBS to this in Bobterm:

ATDL
ATDI jybolac.homelinux.com 800

You could also to the following, if you are running on your linux/unix box
and want to telnet from atari800:

ATDL
ATDI localhost

(Of course, be sure to turn on ASCII translation in the terminal program).

You can also telnet to atari800 by doing the following at any linux
prompt:

telnet <machinename> 9000

Also, everything that can be done in the 850 manual as far as XIO commands
are concerned can be done as well.




To sum up,  the R: emulation can be used with terminal programs like
Bobterm and Ice-T, as well as BBS programs like carina and bbs express.

I have tested it with bobterm, Ice-T and Carina, but not Express, yet.




Again, feel free to email with any questions, until I can write a full
document/web-page on it.

Cheers,
Chris

===

> > The basic use of the R: emulation is that it emulates an Atari 850.
> 
> What is it? A printer? I never heard about it.

The 850 interface is an RS232 device, for connecting non-Atari-specific
modems (unlike the SX212, which had an SIO port, so didn't need an 850),
and other 'serial port' devices.  (Think COM1, COM2, etc. under MSDOS,
or /dev/ttyS0, /dev/ttyS1, etc. under Linux)

-bill!

===

It was called an "Interface module".  It provided 4 RS-232 serial ports,
one was fully functionaly, the others were stripped down.  It also
provided a parallel port.

> Do you think this can be misused by hackers? Again not joking. We need
> to keep an eye on this.
>

Anything can be exploited by hackers!  :^)  However, port 9000 only is
enabled if you run a terminal program, so normal game operation wouldn't
be a problem.  Also, I put this at port 9000 so that normally it would be
found, but there are always port sniffers.  I would think it would be a
problem only if there was a bug in a buffer overflow and you were running
atari800 as root.  But, I know of no problem currently....not saying that
there is no problem.

So, yes, it could be misused, but only if you are running a terminal
program or a bbs program.  ( I cannot say that my code is foolproof :)

However, the R: device it is normally not on, and can only be turned on
(thus, enabling port 9000), after run a program that calls the XIO
commands for the R: device or you write a basic program that reads/writes
to the R: device.  So, normally I would say that it is safe.

--Chris