DryIce behaviour after a device power off/on.

moises_reyes — Mon, 17 Sep 2018 13:36:06 GMT

Hi NXP team,

Our company has already signed an NDA, and I'm not sure where to post a question about the DryIce module. So please correct me if this is an inappropriate place.

We're using the DryIce tamper module in a K81 family processor.

Tampers Enabled:

- Temperature

- Voltage

- Clock

- Monotonic overflow

Tampers Disabled:

- Flash Security (disabled for debug purposes)

- Security

- 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.

Re: DryIce behaviour after a device power off/on.

vicentegomez — Mon, 17 Sep 2018 20:41:54 GMT

Hi Moises

As you already know the dryIce module is under NDA, so please help us to enter a service request on the following link in order to help you.

Support requests

Vicente Gomez

Kinetis MicrocontrollersのトピックDryIce behaviour after a device power off/on.

DryIce behaviour after a device power off/on.

Re: DryIce behaviour after a device power off/on.