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CCS/MSP430F2617: MSP430F2617 programming circuit - 'Unknown device' and no SBWTCK pin

Part Number: MSP430F2617
Other Parts Discussed in Thread: MSP-FET

Tool/software: Code Composer Studio

Hi all,

I've designed and fabricated a circuit based on a MSP430F2617 reference design, but I fear I've overly abbreviated the programming circuitry. At the very bottom my KiCAD design is pictured, you can see I've directly wired TCK, TMD, TDI and TDO. I'm programming the board with the new MSP-FET and getting the 'Unknown Device' error in Code Composer Studio.

First off I think my initial mistake was there is no pull-up on pin 1 (TDO), am I right in saying this would completely prevent functionality?

Secondly I've left pin 8 unconnected, which according to this TI reference page on programming circuitry should be connected to a pin on the MSP430 called 'TEST/SBWTCK', which doesn't appear to exist on the core I'm using, therefore what should this pin be connected to instead?

Thirdly there's no resistor linking pin 7 (TCK) and pin 8 (TEST/VPP), does this also prevent functionality?

Hopefully I've covered my mistakes, but if anyone can root out more I'd be really appreciative - I'm dead in the water until I can figure out the root cause of the board's unresponsiveness.

Many thanks,


  • Hi Louis,

    First, yes you need the pull-up resistor on TDO for communication with that pin to work correctly.

    For your next 2 points, they are related. Those pins do need to be connected with a resistor as shown on the page that you referenced, and they need to be connected on the MSP430 side to the TCK pin (please see the datasheet for the corresponding pin number for your package type).

    Everything else looks fine at first glance, but please make sure that you have followed the page that you referenced and the device datasheet.

  • Thanks for the prompt reply. So the pull up is for 'Spy-Bi-Wire' programming, but is this circuit sufficient for the standard '4-Wire JTAG' programming, as mentioned on the webpage?
  • Hi Louis,

    It should be, as long as the RST pin is connected correctly as well.