When a byte is received over serial, the individual bits are set on the individual digital lines connected to the printer’s parallel port. At this point, the strobe line is pulled low ...

The I/O bus from the CPU to the peripherals is a parallel bus (16, 32 or 64 wires, etc.). Although sounding similar, a serial bus differs from a serial port. Both use serial transmission ...

Because there was only one serial and one parallel port on the computer, the key acted as a pass-through so that other keys and peripheral devices could connect. In fact, the nickname "dongle" was ...

Then he realized, why not make a simple printer port add-on that looks like a printer, but sends the data over USB as a serial stream? On the hardware side, the custom PCB (KiCAD project ...