We're using the DryIce tamper module in a K81 family processor.
- Monotonic overflow
- Flash Security (disabled for debug purposes)
- Time Overflow
In a debug session (using MCUXpresso IDE v10.2.0_759), i am able to read the DRY_SR with a value 256, which is normal because the "Flash Security" is disabled but if i go out of the IDE environment turning the power supply off and then turn it on again i read a value 258 from the DRY_SR register, then the DRY_SR register is cleaned and shows again the expected value 256. Every time that i turn off and on the power supply obtain the same behaviour.
So, i think that, when the power supply is turned off a Tamper is triggered and the "Tamper Acknowledge Flag" is settled in the next start.
Based in the previous scenario....
1- There is a way to obtain more information about what "Tamper" is being triggered? or how avoid this behaviour?
2- What that´s mean "Outside the valid range" in the DRY_SR -> VTF register?
3- What that´s mean "Outside of specification" in the DRY_SR -> TTF register?
Thanks and have a nice day.