README.md

 # AutoBrightness
 
+Simple solution to measure ambient room lighting conditions with an AtTiny85 based USB lux sensor and set external display backlight intensity accordingly via DDC/CI.
 
+See [this blog post for details](https://www.xythobuz.de/auto_brightness.html).
+
+## Sensor
+
+Uses a [Digispark Rev. 3 clone](https://www.az-delivery.de/en/products/digispark-board) with a [GY-302 BH1750 breakout board](https://www.az-delivery.de/en/products/gy-302-bh1750-lichtsensor-lichtstaerke-modul-fuer-arduino-und-raspberry-pi) connected to the I2C bus.
+
+[![Front of PCB](https://www.xythobuz.de/img/autobrightness_pcb_1_small.jpg)](https://www.xythobuz.de/img/autobrightness_pcb_1.jpg)
+[![Back of PCB](https://www.xythobuz.de/img/autobrightness_pcb_2_small.jpg)](https://www.xythobuz.de/img/autobrightness_pcb_2.jpg)
+
+### Quick Start
+
+Check out the repo and required submodules.
+
+    git clone https://git.xythobuz.de/thomas/AutoBrightness.git
+    cd AutoBrightness
+    git submodule update --init
+
+Build the firmware and upload it.
+
+    make -C sensor upload
+
+Prepare udev rules for our new device.
+
+    sudo cp sensor/49-autobrightness.rules /etc/udev/rules.d/49-autobrightness.rules
+    sudo udevadm control --reload-rules
+    sudo udevadm trigger
+
+## Client
+
+### Quick Start
+
+Install dependency and run the client.
+
+    yay -S python-pyusb
+    ./client/brightness.py
 
 ## License
 

client/brightness.py

 import time
 import influx
 
-filter_fact = 0.9
+filter_fact = 0.99
 
 c_in = 0.6, -30.0, # in_a, in_b
 calibration = {
 
             try:
                 influx.write("brightness,location=pc-back", "lux", brightness)
+
+                for d in disps:
+                    name = '_'.join(d["name"].split())
+                    influx.write("brightness,location=" + name, "backlight", d["prev"])
             except:
                 pass
 
             for d in disps:
                 val = lux_to_disp(d["name"], brightness)
                 if val != d["prev"]:
-                    d["prev"] = val
-                    print("{}: Setting \"{}\" to {}".format(time.ctime(), d["name"], val))
-                    ddc.ddc_set(d["_id"], val)
-
                     try:
-                        name = '_'.join(d["name"].split())
-                        influx.write("brightness,location=" + name, "backlight", val)
-                    except:
-                        pass
-
+                        print("{}: Setting \"{}\" to {}".format(time.ctime(), d["name"], val))
+                        ddc.ddc_set(d["_id"], val)
+                        d["prev"] = val
+                    except Exception as e:
+                        print(e)