SLAAE30 July   2021 MSP430FR2355

 

  1.   Abstract
  2.   Trademarks
  3. 1PIR Design Description
    1. 1.1 PIR Sensor
    2. 1.2 PIR Signal Chain
      1. 1.2.1 Traditional Motion Detection Signal Chain Design
      2. 1.2.2 Capacitor-Free Signal Chain Design
  4. 2Software
    1. 2.1 Software Architecture
    2. 2.2 Software Flow Chart
    3. 2.3 Power Profile
    4. 2.4 Data Processing
      1. 2.4.1 Digital Signal Conditioning
      2. 2.4.2 Low-Pass Filter for Temperature Drift
      3. 2.4.3 Spikes and Noise
      4. 2.4.4 Motion Detection Function
  5. 3Hardware and Schematic
    1. 3.1 MSP430FR2355
    2. 3.2 Schematic
  6. 4Results
    1. 4.1 Distance: 15 ft (4.5 m)
    2. 4.2 Distance: 22.5 ft (6.9 m)
    3. 4.3 Distance: 36.5 ft (11.1 m)
  7. 5Summary
  8. 6References

2 Software

Software is a powerful piece of the MSP430 PIR Motion Detector. As mentioned, the software controls the analog signal chain and feedback loops. The signal is also being sampled via the ADC, which allows digital filter techniques to be applied to the detection and feedback loops. This application note includes source code for the PIR motion detection demo. This demo software is intended to accelerate the development of a PIR solution using MSP430FR235x MCU, but this software is only a part of a complete system and is intended to be used only as a reference.