Complex sentence: Any Amiga printer driver had to communicate though the standard Amiga printer.device (the default standard hardware device of Amiga dealing with printers), and the standard parallel.device (which controlled parallel port) and the driver would then control the printer on its own.
Split into simpler sentences: Any Amiga printer driver had to communicate though the standard Amiga Printer. Device (which controlled parallel port) and the driver would then control the printer on its own.