The MSP Access command allows transfer of data to and from the connected microcontroller. In the example shown, the MSP Access command and 6 bytes of configuration data are sent from the base station to the TMS37157 via the low frequency air interface. The configuration data tells the MSP430 how many times to blink the red or green LED. The TMS37157 detects that an MSP Access command has been received and wakes the microcontroller through the BUSY or VBATI pin. The microcontroller reads the status using the SPI command “Get Status”. The MSP access request is than detected, and the microcontroller asks for the data. The PaLFI transfers the data to the Microcontroller via the SPI command “MSP Read Data from PCU”. The data bytes are processed and actions executed. If necessary, the microcontroller sends response data bytes back to the TMS37157, using the SPI command “MSP Write Data to PCU”. After the TMS37157 has detected removal of low frequency power, the response data bytes are sent back to the base station to indicate the command was successful.