+ for reading in by pinmux.
+
+ files generated:
+ * interfaces.txt - contains name and number of interfaces
+ * {interfacename}.txt - contains name of pin, type, and bus
+
+ type may be in, out or inout.
+ if type is "inout" then a THIRD optional parameter of type
+ "bus" indicates whether the bus is ganged together. in
+ future this may be "bus1", "bus2" and so on if an interface
+ contains more than one ganged group.
+
+ basically if the function needs to control whether a group
+ of pins shall be switched from input to output (as opposed
+ to the *pinmux* via user control deciding that), bus is
+ the way to indicate it.