Early parallel ports were often used for hacked "GPIO" applications, they gave you more useful lines than a serial port and were often less picky about the volt

Early parallel ports were often used for hacked "GPIO" applications, they gave you more useful lines than a serial port and were often less picky about the voltages. The "Speech Thing" [1] is the most commercial example I can think of, until "laplink" hit. [1] https://en.wikipedia.org/wiki/Covox_Speech_Thing https://en.wikipedia.org/wiki/Covox_Speech_Thing