The MSP430AFE2xx EVM is divided into the metrology portion that has the MSP430AFE and the application portion that has the MSP430F6638 with galvanic isolation. The MSP430AFE is a slave metrology processor and the MSP430F6638 is the host/application processor interfaced to an LCD, RF and USB connectors. The two MSP430 devices communicate through digital isolators via serial peripheral interface (SPI) or universal asynchronous receiver/transmitter (UART). For further details on the EVM refer to the application report which highlights the hardware and software implementation in the EVM and more instructions on how to run the Energy Meter Demo.