[Coco] CNR Engineering SP-3 (serial to parallel interface) - Manual?

[Andrew]

Art, if I'm understanding you right, I just need to use regular serial 
port output commands (either POKEs or PRINT #-2), at the proper baud 
rate the device is set up for (it has a switch), and I just need the 
centronics pinout to know which pin is what for the data output?

My thought is to use the output for general device control, maybe 
controlling relays (either a pre-built relay module or via a transistor 
of course), or maybe steppers, etc - I might get a hair up my butt and 
try to send PCL to one of my HP LaserJet printers.

The device has a couple of rotary switches on it; one to select baud 
rate (300 - 19200), and another to bypass it (turn it off), or select 7 
or 8 bit (output I guess?). It has three cables and a power supply 
hard-wired (it appears) to it. One cable is the centronics interface, 
then other two are 4-pin DIN connectors (one male and one female).

-- 
Andrew L. Ayers
Glendale, Arizona
https://github.com/andrew-ayers

> Message: 5
> Date: Sat, 22 Dec 2018 16:02:08 -0500
> From: Arthur Flexser<flexser at fiu.edu>
> To: CoCoList for Color Computer Enthusiasts<coco at maltedmedia.com>
> Subject: Re: [Coco] CNR Engineering SP-3 (serial to parallel
> 	interface) - Manual?
> 
> Generally, these interfaces required little in the way of documentation.
> You basically just plug one end into the CoCo's serial port and the other
> end to the (old style, dumb) printer.  There should also be something for
> setting the baud rate.  That's about it.