[ButcherMan]

If one really looks into the code, you can see that usr_SerialDrv.c and PicSerialDrv.c are nearly identical (IFI alludes to this in their FAQ). The PicSerialDrv.c was used for the DDT and later changed for the “user_” naming convention (according to IFI’s tech support). These are just driver templates and give the user the ability to handle his own read buffering if need be. The callback function (located in the CheckUartInts routine) is primarily used for building your own state machines based on a unique device protocol (like the Breaker Panel Board or the CMU2 camera).

Serial_ports.c provides read buffering on either port. It will require you to use a parser to parse incoming data and sometimes this takes more resources than just using a simple state machine to record the incoming data and set a flag indicating that the data is available.

Each driver has it’s own trade offs and that’s were the fun begins.