Well, I've managed to get a little bit further - testing on the MSP-430FR5969, but only get output of:
Card detected
100110 , 100000
(repeatedly, in loop)
even though there's no card anywhere in proximity!
Did this by carefully adhering to pins_energia.h pin mappins for this specific card, in the IDE hardware section.
Now, the big question: Even though the IDE recognizes the EK-TM4C129 - I've installed support for it - where is the corresponding pins_header file for this card? The TM4C129 is the ultimate target here anyway.
And thanks for your feedback.