Hello,
Code Composer Version: 5.3.0.00090
Chip P/N: MSP430F5438
MSP430 DLL Version: 3.02.04.005
I have a board with an MSP430F5328 chip I have been programming for the last several weeks. It seems that every so often, the chip will suddenly stop responding to JTAG resets, or CCS will give a security fuse blown error. If I swap the chip out, the device will program once or twice, and then suddenly the CPU will halt during any debugging.
I've read many other posts regarding security fuse blown or unknown device, and they all seem to indicate that the developer was making some sort of improper JTAG connection, etc., not having enough capacitance on reset. Basically, the posts all lead to the same suggestion: there was a mistake in the JTAG configuration. However, in my case, I know my JTAG connections are exactly correct (as of the latest Hardware Tools User Guide), that I've had success programming the chip with these connections, but suddenly I have errors like "Unknown Device" and "Security Fuse Blown" happen out of nowhere.
I think Jens-Michael Gross had a lot of helpful advice in this post: http://e2e.ti.com/support/microcontrollers/msp430/f/166/t/164648.aspx
The problem is that if I do a mass-erase, I am only able to program the device successfully once or twice, and after a few times, I get either an "Unknown Device" or "Security Fuse Blown" again.
Best
Russell