This app note shows how to connect a DS1390 to a Motorola DSP that has a built-in SPI interface module. This circuit uses the Motorola DSP56F800DEMO Demonstration Board and CodeWarrior IDE. Description The DS1390 Real-Time Clock (RTC) may be interfaced with a microcontroller (μC) or Digital Signal Processing (DSP) unit using a SPI interface. This app note shows how to connect a DS1390 to a Motorola DSP that has a built-in SPI interface module. This circuit uses the Motorola DSP56F800DEMO Demonstration Board and CodeWarrior IDE.