This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

SPI problems while debugging with MSP-FET430UIF

Other Parts Discussed in Thread: MSP430F5342, MSP-TS430RGZ48B


My name is Nir and at the moment I'm implementing an SPI channel using MSP430F5342 on it's target board - MSP-TS430RGZ48B.

It seems to work fine but whenever I connect the MSP-FET430UIF debugger, it drives the MISO line to '1' logic and ruins the spi communication between the MCU and the sensor it operates.

In order to make it work fine I physically disconnect the debugger from the target board. As soon as I do so, MISO line works again. I'll also mention that the SCLK and MOSI lines works fine even when the debugger is connected.

Do anyone have an idea what may cause it and how can I use the debugger without damaging the MISO operation?



  • Nir Klein said:
    it drives the MISO line to '1' logic

    Which one? The MSP has four SPI interfaces and therefore four SOMI lines.

  • I'm using B1 channel at the moment

  • Strange. USB1SOMI has nothing connected to it on the board itself. And the existence of debugger or not shouldn't affect it at all. The debugger may stop clocks (on breakpoint hit) but won't change port configs. And the pin isn't required internally for anything.

    I guess you have set JP5 to 10 properly, to make the JTAG work, but even if not, this shouldn't affect UCB1SOMI.

    Maybe connection of the debugger affects your SPI slave? If the MSP is master, then a constant high SOMI indicates that the SLAVE is driving the line high, possibly not detecting the clock anymore - or not being selected anymore (which pin do you use for chip select?)

    It could be an issue with supply voltages when the debugger is connected.