Object ranging is essential in many types of systems. One of the most popular ranging techniques is ultrasonic ranging. Ultrasonic ranging is used in a wide variety of applications including:
• Autofocus cameras
• Motion detection
• Robotics guidance
• Proximity sensing
• Object ranging
This application note describes a method of interfacing PIC16CXXX microcontrollers to the Polaroid 6500 Ranging Module.
Their design uses the Polaroid 6500 ranging module interfaced with the PIC by using a pair of digital output pins and one CCP input pin. One digital pin (INIT) starts the module, while the other (BINH) provides a blanking interval during which the module does not respond to revived signals. The CCP module is setup to time the interval from initializing the module to the time an echo is received. Assembler source code is provided by Microchip.