about the volatile key with a tamper-protection bit is programmed

[xiujian]

On the cyclone10GX evaluation board, the VCCbat is not connected to the battery, but is directly connected to the 1.8V power supply. After the power is turned off, the volatile key will disappear. If a volatile key with a tamper- protection bit is programmed, after the power is turned off and on again，what happens when the volatile key without a tamper-protection bit is programmed? 

[Ash_R_Intel]

Hello,

Once the tamper-protection bit is set, it burn the fuse. This cannot be undone. So, be careful before exercising this feature. Go through the user guide and application note AN556, https://www.intel.com/content/www/us/en/docs/programmable/683269/current/steps-to-enable-tamper-protection-bit.html

Regards