A proximity alert system has been designed and implemented using the following elements:
• The HC-SR04 Ultrasonic Ranging Module;
• The STM32F746-DISCOVERY board;
• The Linux OS.
The STM32F746-DISCOVERY reads the distance of any object located in front of the HCSR04
sensor, and then it blinks the user led with a period proportional to the distance,
according to the following table:
| Distance [cm] | <10 | [10-25) | [25-50) | [50-75) | [75-100] | >100 |
|---|---|---|---|---|---|---|
| Period [ms] | ∞ | 400 | 600 | 800 | 1.000 | 2.000 |
The STM32F746-DISCOVERY prints on its serial console the measured distance.