JTAG Secure mode

Hello guys,

I'm looking for more information regarding the JTAG Secure mode.

It's mentioned a little in the MAX10 Configuration Guide: https://www.altera.com/en_us/pdfs/literature/hb/max-10/ug_m10_config.pdf

But I still don't get a full picture.

I wonder if the JTAG is "LOCKED" by user logic or is there some kind of permanent switch that forces the device to go into that mode right after power on.

If it's done by user logic, does it mean that, if I hold nCONFIG low, I will be able to erase the internal flash and get out of that "JTAG secure" mode?

I appreciate your sharing of knowledge.

Jeff