I have the virtuabotix PIR motion sensor, that I want to use with the FRDM-KL46Z board. Upon tripping the sensor it should turn on the on-board and external LEDs on. However it doesn’t.
I hooked up the sensor to an oscilloscope and a DMM to check out the high and low logic voltages. High output is 3.3v and low is 2.8-3.0v. The input voltage is set to 4 volts.
Also, when I trip the sensor, the output stays high for a very long, if it does, no matter where I set the latch pot.
Do I have a bad sensor or am I doing something wrong?
A couple questions, first it sounds like you are powering the board at 4 volts, have you tried powering it with 5 volts? The output should be at 3.3 volts, but the low should be below 2.0 volts. Minimum latch time is two seconds, so if you can’t get it to latch at 2 seconds then you may have a damaged control knob.
Let me know what happens when you put the PIR motion sensor on a 5V rail, and if it still isn’t working I can help you debug further or get you a replacement.
Thank you for the quick response. I will try this weekend, if not Tuesday at school I will be working with it!
Hi Mr. Datillo,
I found out the problem, it was not the sensor, it was the board. Even though it was sending out a 5v output the board didn’t accept it as a logic 1. I had to change the code to accept the signal as analog, then the code translated it to a digital 1. It works great now!
Whoops! I meant 3.3 V signal!