I have an Esprit 250c Modular Color RS/232 Terminal
"Intelligence
Unit"
( overview here, and pdf of features here )
I would like to make it work as a text-based tty terminal, maybe VT100
as it seems to be one of the most common standards.
Here are the connections this device has:
I also have a PC with a 9-pin serial port that I have running Ubuntu 14.04 and access to PCs and Macs.
I have been looking into the utilities like putty
, screen
, minicom
, kermit
and so on. I also read up on the LTSP project and watched a few videos on how to create Ubuntu thin clients on YouTube.
I have been reading up on things like the Text Terminal How To which seems to be one of the most complete resources but I still have a few questions.
I'm very comfortable with Linux and understand the basics of how things like named pipes work and, and the history behind why terminals sessions are referenced as /dev/tty1
etc.
I get the impression that I'm doing the opposite of what most people are doing - namely using a terminal emulator program to connect to a remote "server" rather than trying to figure out how to create a "terminal text server" to power an antiquated device.
Nevertheless, I have several questions regarding the "next steps" of my project:
- I'm assuming I can run something like
minicom
on my linux box and connect the Esprit directly to that using the serial port. But... - How does the "handshake" work? Do I need to configure specific settings on both devices to allow them to talk? ( baud rate, dialing string, etc. ? )
- Or once you plug in the serial cable is it really just as simple as if you pipe text to
/dev/ttyS0
have have it show up on the monitor of the Esprit? - If configuration does need to take place, do I need a special keyboard to access this? According to this chapter it seems like there used to be a few extra keys on most terminal keyboards, like the "setup" key, which are apparently no longer included in a standard 101-key keyboard)? If not, how do I press "setup" on a standard keyboard? ( I could not find any manuals with instructions for setup for the Esprit 250C )
- Does having a serial cable with more pins work differently from the smaller serial cable that has only 9 pins? Do serial ports with more pins work at a higher speed?
- This device came with a plastic adapter for the bigger serial port (
Serial 1
) and on the back side is an RJ45 plug. It is labeledMODEM CAB-5MODCM
. What is this for? It looks like it would allow you to do a serial connection via an RJ45 plug or RJ11 plug which I believe have 8 and 4 wires respectively. How many wires are used in the minimum RS232 communication? 6? 4? 2? - Any suggestions on specific next steps or common pitfalls to avoid?
- If using something like an serial to RJ11 or RJ45 adapter, how do I know what pins to use? I've seen several of these with 'configurable pins':