..... My understanding is that I can setup any printer to use a serial or parallel connection. I have the serial cable, is there any reason why serial would not work but parallel would?
Can I ask where you came to that "understanding?"
And the reason that some printers came with an RS-232 interface was to connect to Apple computers that only came with serial connections. Old and obscure printers that lack a manual stating the requirements for an RS-232 interface in terms of Baud, protocol, and stop bits, can be connected by trial and error. I worked in a computer project that it only took 3 weeks of constant, 8-hour day (paid) work to accomplish this. If three bucks would have fixed the issue, I'm just guessing, mind you, that someone would have chipped it in.
If you a so head strong that you are determined to do it "your way" [thank you, Frank Sinatra], locate Apple's serial protocol, set the Amiga's serial port to match it, and send all printer output to the serial port -- use "text.txt > SER:" for testing.
Forty years of computer experience, a degree in Computer Science from a private university, 29 years of Amiga ownership and use, and I end up telling people how to save three dollars on a cable that most folks threw away 10 years ago...
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