Is there any way for the Serial port to detect continuity?

Like if i have 3 switches how could i detect weather they are on of off? Keep it simple,thanks. Edit:its the 9 pin serial port

orksecurity8 years ago
If it's full RS232, rather than the simplified nine-pin version, a lot of those extra pins were for status/handshake signals and could be made to work for this purpose. (Abusing a serial port as a small parallel port; ugly but could work.) If it's a small-connector RS232, you'd need to actually use the serial data channel... which means having some circuitry to convert the input bits into serial form and send 'em when the computer says it wants 'em. Or send the update when they change and have the PC's hardware driver respond to an interrupt triggered by the port, which is what typical PC keyboards do.
ReCreate (author)  orksecurity8 years ago
Eh,no i can't do that Is there any workaround for this? Like how they did it in the track how far your hamster runs instructable?