We discovered that in 1983 Morex created a simple product capable of driving a printer in serial and parallel mode, with a very basic hardware support and clever software support.
The Morex interface was widely cloned in Italy and Spain and probably also elsewhere in the world.
It features a bidirectional rs232 software driven interface, with the timing for the baud rate adjustable to run in contended memory (the documentation suggests not to go much higher than 600/1200 bps, if so).
The new library file is rs232morex.lib and is totally untested, it just builds
I had the code at hand and wouldn't want to waste the effort we put in investigations. Should anybody want to test or improve it, just show up.
If you have an early serial+parallel interface (also self built), there's a good probability it's a Morex clone.
Known equivalents are the Indescomp ones, the B&V Interface, the Elettronica 2000 interface schematics.