Many of the MSP430Microcontrollers have either the Timer_A module or the Timer_A and Timer_B modules included in them. These modules contain a 16-bit Counter that CAN be incremented from a number of Clock sources. They CAN even count in low power modes. These timers also have a number of capture/compare Registers that lend themselves to a variety of applications. One of these applications is the Automatic generation of a PWM output to control a DC motor. This application note demonstrates one of the many potential Motor Control schemes that are possible using the Timer_A and/or Timer_B modules.
The TI TPS77133 shown in the example circuit provides both the regulated VCC to the MSP430 and a power on reset signal to control the reset input of the MSP430 The TPS77233CAN be used if the supply Voltage Supervisor (power good) function is required. Reference  is the datasheet for this device family.