MSP430 evaluation and prototyping cards

If are using the evaluation kits from TI, there are a couple of points to beware of.

If you are running your MSP430 chip from less than 3.6V, make sure you've removed the zero ohm link r8, and refitted it as r9. If you do not do this, all sorts of things can go wrong. The JTAG interface will try to drive signals referenced to the parallel-port's 5V signals. It seems this then messes up the MSP430 whose core is running on whatever rails you've decided upon externally.

More details on this are provided by Texas's own document on the CDROM that came with the FET kit. The CDROM is nearly un-navigable, but the file you want is "./Literature/Literature - MSP 430/User's Guide/FET Users Guide/MSP-FET430P140 Users Guide.pdf" assuming you're starting from the root directory of the CDROM. Page 28 has a circuit diagram. Beware of the minor version differences between the prototyping cards.