MSP432P401R Integration with UltraSonic Sensor and UART

A program which calculates distance from an obstacle using HC-SR04 and displays the distance serially with UART

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Technical Specs

* Embedded-C
* Code Composer Studio
* MSP432P401R
* UART
* Putty
* Ultrasonic Sensor ( HC - SR04 )
* Timers
* Interrupts
* Register Level Code

Prerequisites

• C language
• Reading MSP432P401R DataSheet and Technical Reference Manual
• Working knowledge of Timers, Interrupts and Interrupt Service Routine

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Description:

• Ultrasonic Sensor has 4 pins. Vcc, GND, Trigger and Echo pins. The sensor gets triggered by supplying 10 microsecond wide pulse. The sensor generates a pulse from the echo pin with a period proportional to the distance of the obstacle from sensor.
• Echo pin from the sensor is connected to a voltage divider which reduces it to 3.3V, tolerable by the MSP, to Port 2 Pin 7.
• Trigger pin of sensor is connected to Port2 Pin 6.
• MSP432 board is connected to a computer via USB

Important Note

1. Remember to supply 5V for HC-SR04

2. MSP432 is not tolerant to 5V input. Use voltage divider ( max voltage => 3.7V )

3. Range of HC-SR04 is 4cm to 200cm

4. Check Device Manager in Windows to find the COM port of MSP432. You'll need to use this information while connecting to a serial console like Putty

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Execution

1. Read description and important note before reading these instructions
2. Create new project inside Code Composer Studio
3. Copy the file contents of MSP432-Ultrasonic.c into your editor
4. Open putty and select serial with COM port ( check device manager ) and baud rate: 9600
5. Execute the code and see values rush to putty

Feedback

Leave any suggestions or issues in the code by opening an issue page

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