The BeagleBone processor AM335X has several pins to communicate with outside chips and components. Some of these are dedicated pins to communicate with the DDR memory chip on BeagleBone. These pins are permanently connected to a memory chip. You cannot attach other components or chips to these pins. The same holds true for the processor's JTAG pins, USB pins, Power IC connection pins, etc. These pins have a fixed role of communicating with respective components/chips. These types of pins dedicated to communicate with single component/chip are specific purpose pins. Users do not have control over these pins individually. The processor with all its pins as specific purpose pins becomes rigid. It becomes less flexible to attach new components and program them.
To provide flexibility to adopt components outside the board, some of the digital pins on the processor are not given any specific role. Users are given the power to control each one of them via software. These pins with...
