The SC14422 is designed to be compatible with many radio interfaces. A dedicated TDMA controller handles all physical layer slot formats and radio control. The integrated National Semiconductor's standard CR16A processor core with external Program memory (Flash or ROM) takes care of all the higher protocol stack. Programmable I/O ports can be configured as chip selects for I/O expanders, Serial Flash memory, interrupt source or I/O. A digital serial interface can be configured to interface to many codecs and ISDN devices with -Law, a-Law, linear or transparent data formats.