homebridge-serial-projector

A Homebridge plugin to control BenQ Projector via RS232 Serial Port and OpenWrt.

Features

• Power toggle
• Mute toggle
• Eco Blank (dim the display) toggle

Requirements

• A BenQ Projector
• A RS232 to USB adapter (Prolific PL2303 chip recommended)
• A RS232 crossover (null modem) cable
• An OpenWrt router with USB port
• An existing home network (wired or wireless)

Installation

1. OpenWrt router preparation

Run firstboot on the OpenWrt to get an clean reset.

1.1. Install packages

# opkg install coreutils coreutils-stty kmod-usb-serial kmod-usb-serial-pl2303 libpthread librt socat

1.2. Install executables

$ scp ./openwrt/fs/root/pctrl.sh     root@ip-of-openwrt:/root/
$ scp ./openwrt/fs/www/cgi-bin/pctrl root@ip-of-openwrt:/www/cgi-bin/

1.3. Install multicast listener

# vim /etc/rc.local

Add

# Keep responding to multicast diagrams
while true; do socat UDP4-RECVFROM:2367,ip-add-membership=224.33.66.77:0.0.0.0,fork EXEC:"echo \"mac_address: $(cat /sys/class/net/eth0/address)\""; sleep 1; done &

exit 0

1.4. Configure OpenWrt as a routed client to your main (wireless) router network

Refer to the OpenWrt Wiki.

1.5. Remember the IP address

Ensure the IP address of OpenWrt router is accessible from the main router network.

1.6. Confirm working scripts

Test the following URLs on your computer connected to the main router network:

• get status: http://ip-of-openwrt/cgi-bin/pctrl/pow/%3F
• turn on: http://ip-of-openwrt/cgi-bin/pctrl/pow/on
• turn off: http://ip-of-openwrt/cgi-bin/pctrl/pow/off

2. Configure Homebridge

Refer to Homebridge repo for more information.

2.1. Install packages

$ sudo npm install -g homebridge # see also: https://github.com/nfarina/homebridge
$ git clone https://github.com/gaomd/homebridge-serial-projector.git
$ cd homebridge-serial-projector
$ npm install

2.2. Edit ~/.homebridge/config.json

{
    "bridge": {
        "//0": "Remove this line and refer to: https://github.com/nfarina/homebridge/blob/master/config-sample.json"
    },
    "accessories": [
        {
            "accessory": "SerialProjector",
            "name": "TV",                           "//0": "required, default to TV (the {name})",
            "power_switch_name": "TV Power",        "//1": "optional, default to {name} Power",
            "speaker_switch_name": "TV Speaker",    "//2": "optional, default to {name} Speaker",
            "display_switch_name": "TV Display",    "//3": "optional, default to {name} Display",
            "mac_address": "mac address of openwrt"
        }
    ]
}

2.3. Run Homebridge

$ homebridge -D -P /path/to/homebridge-serial-projector

2.4. Configure the iOS Home app

Open the Home app on your iOS device.