Control/Dimming Strand MX, MXTERM, 9 pin serial?

TheDonkey

Active Member
OhJeez, my first non-intro thread.

Short Version:
Is it possible to find/build a cheap cable that'll let me plug the 25 Pin Strand MX serial port into a 9 pin serial port and use MXTERM?


Really long version: (Sorryz)
I'm currently a high school student that's taken an extreme liking to tech theater arts, particularly lighting. So much so, that in 6 months, I've had various people with various levels of expertise claim that I know more about our system than anyone else in the school.

The problem with our system, of course, is that it's pretty **** old. The school itself is almost 100 years old.

We currently have and use a Strand MX, fairly decent board, not even close to what the real world uses, but not too bad overall.
Soon as I found out the model, I went and got the manual, in the manual, I found the interesting little tidbit with the connecting to a computer and running a GUI app of sorts.

I immediately jumped on it, talked to the IT guys about getting a second computer in the booth to run as a console, and got the "project" approved, just waiting on them to find something crappy enough to run Dos without wasting power.

After I got approved(last week) I went in and started reading every line of the MXTERM part of the MX manual, and realized something tragic.

Up until that moment, I thought that the MX used a standard LPT parallel port and just wrongly stated it as a serial port.

And I only now realized that what it was referencing to was the 25 pin old style serial port, now I'm not sure, but I don't think that the computer/laptop the IT guys will find will have a "25 pin RS232" port, so I'm looking for some aid.

Will I be able to build a cable that'll reroute the 25 pin cable(of which MXTERM only uses 4) to the smaller 9 pin? Or am I screwed out of ~$30 to get a Serial - USB Cable?

I know how to solder and have spare male and female DB25 plugs laying around, but is the data stream consistent?
 
I used a Strand MX last spring for a show and I used a standard 25pin to 25 pin cable that I had and bought a 25pin to 9pin adapter for $5 from the local computer store, it worked perfect. Just make sure that your 25 pin cable is wired 1 to 1, 2 to 2, 3 to 3 etc. cause there are some out there that are different.
 
Yep, both styles of connector are standard for RS-232 serial. The 25-pin connection allows more discrete signals, of course, but those lines are rarely used, and even a bunch on the 9-pin connector are rarely used -- the important ones are the data lines and one (sometimes a particular one) of the handshaking lines (RTS/CTS or DSR/DTR).

The RS-232 protocol is old and was developed for applications where both the hardware and the software had to handshake, and most of the other signals in that standard I believe were hardware-related.

A couple of years back I set up an old Kantronics TNC with an even-older Apple II+. I had to do some fancy dancing with the handshake lines because the serial card honored all of the handshake lines, but the TNC used only one, leaving the other in a "Not Ready" state .. even though both had 25-pin connectors. I think I ended up cross-wiring the handshake lines and disconnecting the DCD line.

But for most things post-1980, often a standard adapter will work plenty fine.
 
Ok, cool, I'm currently on a job hunt and just came back from a local walk around the neighborhood, stopped in some big box computer retailers and they have the cables for $10.

Now to just get the Drama Head to fund my $10 project which I quoted at $0 :rolleyes:

I'll talk to the IT guys next time I see them, the school's so old there's gotta be a cable laying around SOMEWHERE.

Edit:
By Wired 1-1 would you mean that Pin 1 on the 25 side is Pin 1 on the 9 side and so on?
Would it be possible to know without buying and pulling out a Multimeter?

And what are the other types of wiring are there?
 
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