A microcontroller interacts with other devices through its ports. In this focused on the digital I/O in the MSP430. We reviewed specific registers to set up the digital I/O properties. Then we considered the two related to push buttons. Finally, we designed a real-life application (a digital safe) using digital I/O. We provided all the hardware and software design related to the digital safe. We hope that this information will encourage new projects using digital I/O. Write a C program for the MSP430 to calculate the number of zeros and ones in an array. If the number of zeros is more than the number of ones, the red LED (connected to P1.0 on the MSP430 LaunchPad) will turn on. Otherwise, the green LED (connected to P1.6 on the MSP430 LaunchPad) will turn on