Hiya-
Please note that the windows (at least 98 and earlier)
terminal program says to 'nix boxes that it's a "vt-100"
type terminal, yet does a rather poor job of doing
cursor manipulation, so you might get some rather strange
output. I "think" that it's still bad on XP, I just don't
remember offhand.
I *STILL* use windoze "telnet" to 'nix boxen, and I just
live with the rather poor job of it doing "vi". Sigh.
(control L is your friend).
Seriously, if you are having problems with your windoze
terminal program talking to your robot, try a live CD
version of linux and "minicom" and see if there is a
happier interface. I would use knoppix, but that is just
personal opinion. The 'nix systems have typically supported
a DEC (Digital Equipment Corp.) VT-100 terminal much
more faithfully as a terminal emulator.
If there is no connection at all, i.e. no characters
coming/going from the interface, you might need a
"null modem". This device interchanges pins 2 and 3
(transmit data and receive data) on a serial interface.
They are available in both DB9 and DB25 versions.
Also, the robot might need some EIA conditioning signals.
Failing the null modem, You might have to put TWO
null modems together.
Usually the null modems wrap DTR/DSR CTS/RTS/DCD together
to fool the DTE that the "modem" is happy and connected.
These are high level one signals. In other words a high
is a logic one.
Then we have to use the terminal program to figure out the
baud rate, number of data bits and parity. Those are all
usually configurable from the desired terminal emulation
program.
Finally, having said all that, I too have a "vt-100"
program. I use the serial cable from my Palm 3 and a
small program from the internet for the PDA, it only
uses the "scribble" opps, graffity type input from the
stylus but it's still kinda fun. I use it a lot with
the serial interface of microcontrollers. Nothing with
an intensive I/O requirements. It's one of the
gazillion hits on gooogle.
Hope I didn't scare you off, but without any further
information, these are just some of the variables of
the "vt100" and "serial" interface that we all have to
live with.
Cheers,
Rich S.