BenQ Beamer Binding - RS232 over WIFI & IR Receiver


I’m using a harmony hub to control my projector, Soundbar and various hdmi sources together with an Benq W1070+ projector. Everything fine (even when there is only a one way IR communication between the hub and the devices).

I stumbled over the Benq binding and found it interesting to see the lamp timer and source selection and to have a bidirectional interface to openHAB. I assembled wlan to RS232 bridge using a ESP8266 for under 5€ - nice (If anybody is interested I can post a little how to (no soldering no programming required!). The binding work as expected … BUT. The IR receiver seems to be switched off when the projector is in standby. So the harmony hub cannot switch the projector on again. Switching OFF works, so I think its not a hardware problem. Ups. Switching the Beamer on via openHAB -> WLAN -> RS232 indeed works. This makes sense if you want to limit the access to the projector i.e. Schools or universities.

Do anybody have the same experience (I don’t think many people are using this Binding - who have RS232 connections between openhab and their Beamer and WLAN/RS232 bridges are rare and quite expensive)

I could use a rule to detect if the harmony is in an action where the projector is required and switch the beamer on via RS232. But this could fail and I think it is one unnecessary step.

QUESTION: Can be there a universal way to send any serial commands (not only the few implemented in the binding) to a) use other commands and b) to use the command which seams to activate the IR Port.

Write Remote Receiver-front <CR>*rr=f#<CR>
Write Remote Receiver-rear <CR>*rr=r#<CR>
Read Remote Receiver Status <CR>*rr=?#<CR>

Or did I missed something?


Sorry for my bad english :wink:

OK, as expected there are not many people using the BenQ Binding. So I got away with a rule.

Question: Do somebody knows a Binding / Way to send Terminal style commands (to activate the IR-ports) to a RS232 device which is connected over TCP/IP (IP address / Port). Certainly there os a way in Linux but I’m a 100% noob and looking for a platform independent solution.

rule "Logitec Harmony hub changed"
    Item Media_GF_Living_Satus changed
  	switch (Media_GF_Living_Satus.state) {
  		case "Playstation 4" : sendCommand(gf_wohnzimmer_multimedia_projectorPower,ON)
		case "Fernsehen" : 	sendCommand(gf_wohnzimmer_multimedia_projectorPower,ON)
		case "XBOX 360" : 	sendCommand(gf_wohnzimmer_multimedia_projectorPower,ON)
		case "Apple TV sehen" : sendCommand(gf_wohnzimmer_multimedia_projectorPower,ON)
		case "Filme von Festplatte" : sendCommand(gf_wohnzimmer_multimedia_projectorPower,ON)
		case "Musik hören" : sendCommand(gf_wohnzimmer_multimedia_projectorPower,OFF)
		case "PowerOff" : sendCommand(gf_wohnzimmer_multimedia_projectorPower,OFF)
		case "FERNSEHEN SCHLAFZIMMER" : sendCommand(gf_wohnzimmer_multimedia_projectorPower,OFF)


I’d be interested in the ESP8266 RS232 bridge. I plan to use it with a Epson projector, but I figure that should work, too.
Thanks in advance



it is totaly easy and you have luck that I’m just sitting in front of boring work and need some deflection.

You need an ESP8266 board: Wemos D1 mini (2,5€ , Node MCU or any other board with USB/TTL converter and 5V to 3.4V regulator will do. Or a ESP01 module if you prefer the hard way and save a few bucks :wink:.
Than you need a RS232 to TTL converter board with a MAX3232 (certainly others will do the job too) and 4 female to female jumper wires (in some modules included). You can get this for 1€. Connect GND and 3.3V. Connect D7 (GPIO15) to TX and D8 (GPIO13) to RX.I Removed the screws and metal shield to plug it into my projector directly.
Finally a minimum 500mA USB plugpack. I used an old charger with 500mA. The ESP is well known for his power spikes during transmission and most boards do not have a sufficient capacitor to compensate this.

I used the ESP-Link firmware follow the instructions to flash and first connection. There are other Firmware available like ESPeasy.

I played around with different pin settings … this worked for me:
ESP-Link Pins

I picked the ESP-Link firmware because it gives you a “man in the middle” debug function using the build in console feature. My Bridge is running for more than one year 24/7 without any problems.
In the future I will try to use use the HTTP Binding and program the features I need because the dedicated binding crashes after a few weeks and I have to restart openHAB to get it up and running.

Would be nice to see your result.


Thanks you very much, I just ordered everything and will get back to you as soon as everythings here.


I finally got all the parts an found some time to try it out. Unfortunately the voltage regulater in my Wemos seems to be broken, I can’t power it by USB, only through the header pins. None the less it worked from the console on esp-link.
In the next days I will try to add it to openhab.

Hi there, have you moved your setup to the HTTP binding? How did you included the ESP in this setup?
I’m trying to realize such a setup with a EPSON beamer. My problem is that the original EPSON binding tries to poll the serial port every few seconds & this does not work with the ESP-Link firmware. Manually sending commands to the port through the uC in the webinterface works fine.