I have an MSP430FR5969IRGZ chip and a MSP-FET430UIF programmer and am trying to program it with 2-wire SBW mode. When I try to do this with the MSP430Flasher tool, it acts as if the device is not present and returns an "Unknown device" error.
As far a I can tell from the documentation, the chip should be in default SPI-BY-WIRE programming mode by default and this requires only 2 pins plus power/ground to program. I have hooked up the following 4pins between the device and the programmer: 3.3V, GND, nRST/SBWTDIO, TEST/SBWTCK. I've verified the connections and can see activity on both SBW pins using a scope. nRST/SBWTDIO has a 47kOhm external pullup and a 470pF cap to ground. TEST/SBWTCK is connected directly.
So why isn't 2-wire mode working here?
If I also connect the other JTAG pins (TMS, TCK, TDO, TDI), the programming is successful. I suspect it is using 4-wire JTAG mode, but as the flasher doesn't allow you to specify the mode, this is only a guess.
Here is the output when only the SBW pins are connected (plus 3V3 and GND):
C:\ti\MSPFlasher_1.3.20>MSP430Flasher.exe -e erase_all * -----/|-------------------------------------------------------------------- * * / |__ * * /_ / MSP Flasher v1.3.20 * * | / * * -----|/-------------------------------------------------------------------- * * * Evaluating triggers...done * Checking for available FET debuggers: * Found USB FET @ COM5 <- Selected * Initializing interface @ COM5...done * Checking firmware compatibility: * FET firmware is up to date. * Reading FW version...done * Setting VCC to 3000 mV...done * Accessing device... # Exit: 16 # ERROR: Unknown device * Powering down...done * Disconnecting from device...done * * ---------------------------------------------------------------------------- * Driver : closed (Internal error) * ---------------------------------------------------------------------------- */
