Serial Controlled Power Outlet


[Alan] sent me his simple rs-232 controlled power outlet. He built it to turn on his laser printer when a print job appeares in the queue. The relay is directly controlled by the DTR line on the serial port. Lots of espresso machine PID conversions use them to run boilers, so he could have avoided the extra mechanical relay. [I can’t pick on him too much, my old laserwriter is on all the time.]

He tied it together with some perl to turn on the printer and get the print job going once it’s had enough time to initialize.