Peripherals—IP2022 User’s Manual 274 www.ubicom.com 4.6.1 Protocol Mode Table 4-6 shows the features which are enabled for each protocol,
as controlled by the PRS3:0 bits in the SxMODE register. These
features  affect  which  registers  and  register  fields  are  used,  for
example  the  SxRSYNC  register  is  only  used  in  the  USB  and
10Base-T modes. Table 4-6  Protocol Features PRS3:0 Mode 0000 Disabled None None No No No No 0001 10Base-T   Manchester   Differen- tial Yes Yes No Yes 0010 USB Bus NRZI Differen- tial Yes Yes Yes No 0011 UART None Single- Ended No No No No 0101 SPI None Single- Ended No Yes No No 0110 GPSI None Single- Ended No Yes No No