- implemented as XDRV53
- user must configure GPIO pins "DLP Rx" and "DLP Tx" for serial communication
- emulates an additional RELAY by sending ON/OFF commands to Projector
- continually polls the Projector's state to update virtual RELAY state
- blocks RELAY1 in ON state while Projector is running (to protect the lamp)
- serial codes for NEC and OPTOMA, ready for more manufacturers
- tested with NEC V300W