Hi Domneck S,
It seems the problem is caused only by combined LPCXpresso IDE, JLINK and the new chip(erase all chip flash) together, I have reproduced it on my side.
I also have checked these ways:
1. the CMSIS DAP debugger, mase erased chip(new chip) and LPCXpresso IDE, no problem.
2. JLINK, mase erased chip(new chip) and IAR IDE, no problem.
Maybe you also can consider to use the CMSIS DAP with the LPCXpresso IDE, the LPC-LINK2 have the CMSIS DAP debugger function.
About the problem, I found a way maybe help you, when the new chip downloaded with JLINK and LPCXpress IDE meet the g_pfnvectors error , then exit the debug mode, power off the board, and power on the board, use the JLINK download the code, and click run, the code will work, you can try it on your side.
I will also try to report this problem to our LPCXpresso IDE department.
Wish it helps you!
Have a great day,
Kerry
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------