One of my customers has made a design with MSP430i2031. During their testing of the product, they found that Application is hanging.During debugging, we found that in frequent ac mains on off , TEST and RESET pin expose to noise and suddenly clock output on P1.0 and P1.1 (MCLK and SMCLK) gets stopped while we have configured these pins for clock output. When we grounded Test pins, It worked absolutely fine so we concluded that MSP430i2031 is executing some test mode due to noise on TEST-RESET pin. We are making hardware provisions for this condition, however in their application customer will blow its programmable JTAG fuse. I couldn't find much details of this in user guide except that in startup code of examples, Program looks for two location in Flash and if it is different than 0xFF and 0x00 then it disable JTAG by below instruction:
SYSJTAGDIS = JTAGDISKEY
My query is that even if there is noise on test pin (which executes entry sequence of JTAG/SBW) and we disable JTAG by blowing this programmable Fuse, what will happen? Will MCU ignore this sequence and keep continue application OR Clock module stop similary as today & core will wait for something? Appreciate your inputs on the same...