RCM5600W serial port pin assignments for RS232 lib

Where can I find which port pins have been assigned to serial ports A, B, C, and D Tx/Rx function when using RS232 lib?

The Rabbit 5000 uP can use several different port pins function as tx/rx for A, B, C, and D, however, it’s not clear to me after reading the hardware literature what determines pin configuration. It appears from a note on the poster that SPCR might be responsible for this but when I reference SPCR material no mention of serial port is mentioned.

Please help by providing me with the default assignments used by RS232 lib, as well as a reference to where this information is found.


The default setup is defined between boardtypes.lib and rs232.lib.

boardtypes.lib defines the exceptions for the configuration and rs232.lib sets the defaults if no exceptions are defined.

I don’t see any exceptions for the RCM5600W in boardtypes.lib but there are some for the BL4S100 if you want to see how they are done.

In rs232.lib you will see lots of:

#ifndef x
#define x …

To set the defaults.