JTAG Encrypt (JTAG Enable & Disable) from S32K142 Chip

[harpalsinghjasw]

HI,

Is there any way to enable and disable JTAG port from S32K142 chip.

Thanks & Regards,

Harpal Singh Jaswal

[danielmartynek]

Hi,
I’m not sure what you mean.
The JTAG port can be reconfigured as any other pins.
JTAG-to-SWD change sequence is described in Section 56.3.1 RM, r.7.

Regards,
Daniel

[leo_cheng]

Hi Daniel,

Is there any way to disable debug port(JTAG, SWD, DAP) completely? For security reason, we need to disable the debug port and make sure hardware debuggers(jlink, pemicro, lauterbach, etc) will not work. If needed, we can enable it via other communication interfaces(CAN, UART, etc) with authorization.

[danielmartynek]

Hi leo.cheng@harman.com,

Take a look at this example:

Example S32K144 Verify Backdoor Access Key S32DS1.3 

When the MCU is secure, the debugger has access to MDM-AP control and status registers only.

It can read the Status register and trigger Mass erase in the Control register (56.6.1 MDM-AP Control Register, RM rev.11).

The example shows how to unsecure the MCU using Backdoor key from inside.

BR, Daniel

[santiago_gonzal]

Hello,

Please check chpater 5.2.1.1 of the Reference Manual of S32K1XX.

Regards,

Santiago