Updated Xiaomi Mi Desk Lamp (markdown)

Xiaomi-Mi-Desk-Lamp.md

@@ -22,6 +22,9 @@ To configure it as `Generic`, here is the GPIO assignment:
 - GPIO12: Rotary switch A pin (`GPIO_ROT_A`)
 - GPIO13: Rotary switch B pin (`GPIO_ROT_B`)
 
+NOTE: The operation of the rotary switch depends on the module type being `MI_DESK_LAMP`, so full functionality cannot be achieved with the `Generic` config.
+
+
 # Flashing
 
 This lamp is based on a YeeLight LXU 1.7 module, that contains:
@@ -131,3 +134,20 @@ dhcp server start:(ip:192.168.4.1,mask:255.255.255.0,gw:192.168.4.1)
 add if1
 bcn 100
 ```
+
+## Hacking
+
+The lamp has 3 pins that aren't used in normal operation: ADC, GPIO0 and GPIO15.
+GPIO15 is and must be pulled up for boot selection, so its usability is somewhat limited.
+
+On the other hand, if you already soldered wires to VCC, GND and GPIO0 for serial
+flashing, they are perfect for a DHT11 or DHT22 temperature+humidity sensor!
+
+As the lamp has external power supply, and the leds are in the upper part of the lamp,
+the temperature of the base is the same as of the ambient, and by its nature the lamp
+is situated on your desk, so it's a perfect place for temp+humidity measurements.
+
+If you want to place the sensor inside the lamp base, then you may need to remove some
+material from one of the weight panels, and if you choose to place it on the outside
+(eg. near the base), then a convenient and relatively hidden path for the 3 wires is
+above the power jack, just enlarge the hole by 2 mm-s with a file.