Wondering what the breakdown is for naming the TM4C1231H6PZI7R?
Also, is there an EEPROM failure for the rev 6 version of this board? Similar to what was found on the TM4C123GH6PZI/TM4C123GH6PZI6R.
By failure: (Copied from another I2E thread) A chip that has failed will not communicate over JTAG. I believe this a revision 6 silicon and you are using EEPROM. There is a known errata where EEPROM usage during a power cycle may cause the device to become inoperable. The TDO pin showing a square wave of 60-70ms indicates that it has failed initialization and is an indication of the EEPROM errata.