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LCD/DLP Projector Serial Control~

This feature is not included in precompiled binaries

To use it you must compile your build. Add the following to user_config_override.h:


Mandatory: choose the communication protocol for your Projector (either NEC, OPTOMA or ACER - just one of them) by adding the following to user_config_override.h:


Optional: set the Relay that powers your device (default is 1) by adding the following to user_config_override.h:

#define PROJECTOR_CTRL_PWR_BY_RELAY 1  //the relay that powers the Projector

Optional: set the baudrate to communicate to your device (default is 9600) by adding the following to user_config_override.h:


Optional: enable debugging messages by adding the following to user_config_override.h:


Optional: Add Serial to TCP Bridge to your build if you want to play with your Projector's communication protocol over network connection. Useful for ASCII protocol testing. Needs a different GPIO configuration and is completely independent to this module. Add the following to user_config_override.h:



This driver simulates an additional relay in your Tasmota device. If you have N physical relays and you configure GPIO pin functions DLP Tx and DLP Rx you'll see relay (N+1) after reboot. The two GPIO pins will be used for serial communication with your LCD or DLP Projector. The communication protocol is unique for each manufacturer (compile-time option). The driver polls the Projector's state periodically and updates the fake relay state. When you toggle the fake relay, serial commands are sent to the Projector to power it up or down. While the Projector is running, the driver prevents to switch off the real relay that feeds the Projector. This protects the lamp of the projector (needs to be cooled down before power is cut from the device).

Supported Projectors~

Originaly tested with NEC V300W. All models from NEC should be fine. Commands for OPTOMA devices were supplied but never tested with real device. Acer P1500 was used to implement Acer communication protocol. Fixes and definitions for further manufacturers should go to tasmota\xdrv_53_projector_ctrl.h

Physical connection~

Connect your Tasmota GPIO pins (3.3V TTL level) to a MAX3232 interface (cheap items on internet sales). Such interface changes TTL signals to proper RS232 levels. There are 4 wires on TTL side (Vcc,GND,Rx,Tx) and 3 wires on RS232 side (GND,Tx,Rx). A wire jumper between pins 7(RTS) and 8(CTS) may be needed in DSUB9 connector going to Projector.

Tasmota configuration~

  • set GPIO1 to DLP Tx
  • set GPIO3 to DLP Rx
  • save and reboot

Replace GPIO1/GPIO3 with your scenario. Use command Weblog 3 to see extended logging of serial communication in Console.

Projector configuration~

Check your Projector settings concerning Serial port. It must match Tasmota settings eg. 9600 8N1. Some models have "ID number" feature to allow several Projectors in one room. The control commands in Tasmota contain ID 0. Please switch off the "ID" control completely or set the ID to 0.

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