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docs/Assignments/week_9_input_devices/input_devices.md

@@ -16,9 +16,11 @@ Later on Henk connected a ds18b20 to a signal analyzer and tried reading the pro
 ![alt text](image-19.jpg)
 Here you can see the trigger and the echo pin being pulled to high. 
 
-Here is an example of the RX pin being used when sending data to the MCU. We hooked up the logic analyser to the Rx pin of the arduino to see if we can see the communication
+Here is an example of the RX pin being used when sending data to the MCU. We hooked up the logic analyzer to the Rx pin of the arduino to see if we can see the communication
 ![alt text](image-20.jpg)
 
+We also used a doppler sensor but it worked half of the time. We hooked it up to a led because a pin of the doppler radio goes to high when it detects something but the detection worked really weirdly. It could be because of everyone's presence in the room.
+
 ## Potentiometer/Joysticks
 For this week I want to get proper readings from my joysticks. I got them from aliexpress and couldn't find any datasheets on them. So I gotta test them out myself. With 3.3 volts I got good measurements when sliding the joystick to the lest and bad measurements when going to the right. When fully to the right it was hanging around 2400 and sometimes jittering to 2700. With a controller for a drone I don't want any jittering so I need to figure out how to make them completely stable. On my first board I had a lot of errors. When I was soldering the multiplexer the first time I accidentally rotated it 180 degrees. So I asked Henk for help de-soldering it. 
 ![alt text](IMG_9293.jpg)