View Full Version : [Question(s)] JTAG and I/O pins shared

05-23-2014, 01:56 AM
The microcontroller I am using (TI MSP430G2231) has the JTAG and P1.4-7 are shared. I plan to use the same pins for a motor driver IC (TI DVR8801). Do I need to do anything extra in my circuit design to separate the JTAG and the motor driver circuit? Or is it safe to connect the pins to DVR8801 as pins can be used for JTAG only when the TEST pin is enabled (set high)?


05-23-2014, 12:08 PM
The motor controller won't know that the TEST pin is high, and will actuate when the JTAG pins wiggle.

If you have soft power control for the motor power (through a P-channel MOSFET or something) and default that to off, and/or make arrangements for that to be off when TEST is high, then it's probably safe.

05-27-2014, 12:12 AM
ok. thanks for the tip!