CC1310: JTAG "Halt in Boot" flag

HS FAE Germany

Part Number: CC1310

Hello,
customer has a problem with the JTAG interface. The CC1310 works in a noise environment which may be will be inducted into the TCK pin and then the "Halt in Boot" flag was set. After the next FW reset the CC1310 hangs during boot. A HW reset is not possible in the application. Can this belongs to the recommendation to add an pull-up on the TCK-pin in the chapter 5.4 ICEMelter.

Questions:

- What external pullup resistance value does TI recommend?

- What is the value of the internal pullup resisitor?

- How high is the risk for this behaviour?
* Is there a time frame for the 8 TCK pulses?

- Are there other ways to safely lock or deactivate JTAG?

- Customer detection of this JTAG state (found in the Interne)t:
* bool HIB_Next = ((HWREG( AON_SYSCTL_BASE + 0xC) & 0x400) >> 10);
* Is there any further documentation or idea to detect the "Halt in Boot" flag?

- Is it possible to reset JTAG via FW at runtime?

- Can JTAG be safely locked or deactivated during runtime via FW?

Customer needs a workaround to detect the "Halt in Boot" flag in SW and reset the flag in SW. After that the JTAG should go into sleep again. Is this possible?

Regards, Holger

TRM_ICEMelter_chapter.docx

over 4 years ago

0 SVS over 4 years ago

TI__Genius 9705 points

Hello,

The following post has similar discussion and it might help with the issue you are facing:

https://e2e.ti.com/support/wireless-connectivity/sub-1-ghz/f/156/t/682999?CC1310-CC1310-crash-issue

Regards,

0 HS FAE Germany over 4 years ago in reply to SVS

TI__Mastermind 30505 points

Hello SVS,
I think this is the same issue. Thx.

Can you answer me the other questions:

- in what range do you think is the external pullup resistance?

- What is the value of the internal pullup resisitor?

- How high is the risk for this behaviour?
* Is there a time frame for the 8 TCK pulses?

- Are there other ways to safely lock or deactivate JTAG?

Customer thought about following workaround:
- connect the TCK, TMS pins to a GPIO of the CC1310 and set it to sleep be himself
- detection if the JTAG is wake up can be seen by the "Halt in Boot" flag
Would that work?

Customer claim that this failure is not mentioned in the errata note.

Regards, Holger

0 HS FAE Germany over 4 years ago in reply to HS FAE Germany

TI__Mastermind 30505 points

please answer

0 SVS over 4 years ago in reply to HS FAE Germany

TI__Genius 9705 points

-> You will have to experiment with values for resistor to figure out a value when noise on JTAG is reduced on customer board. It has to be a strong pull up.
-> Internal pull-up resistor value varies with supply and can be calculated using the values provided in datasheet section 5.17. For critical use cases, it is recommended to use external pull-up/pull-down.
-> The recommended fixes are already in the e2e post shared above.
-> There is more documentation on TRM, section 5.4(ICEMelter)

0 HS FAE Germany over 4 years ago in reply to SVS

TI__Mastermind 30505 points

so the workaround in my thread is not working? May be we should do a conf call with the customer to discuss this.

> Customer thought about following workaround:
> - connect the TCK, TMS pins to a GPIO of the CC1310 and set it to sleep be himself
> - detection if the JTAG is wake up can be seen by the "Halt in Boot" flag
> Would that work?

0 Fredrik K over 4 years ago in reply to HS FAE Germany

TI__Guru** 106705 points

Hi Holger,

It is possible for the device to see that the problem has been triggered by polling the JTAG_PD flag (basically check if the JTAG Power Domain has been activated). The only way the device would be able to correct the issue is by tying the reset pin to an IO and do a proper pin reset from the device.

The pull-up on TCK should be as strong as possible with JTAG still being functional. An alternative is to pull TCK to VDDS with a 0-ohm resistor and use the ROM Bootloader interface for production programming.

Regards,
Fredrik

0 HS FAE Germany over 4 years ago in reply to Fredrik K

TI__Mastermind 30505 points

Hello Frederik,

can you send me a code snippet for
- polling the JTAG status
- checking the JTAG_PD

they use the following to check the JTAG status:
bool HIB_Next = ((HWREG( AON_SYSCTL_BASE + 0xC) & 0x400) >> 10);

Is this ok and where is the difference to your proposed solution?

Regards, Holger

0 HS FAE Germany over 4 years ago in reply to HS FAE Germany

TI__Mastermind 30505 points

Frederik,
please reply.

Regards, Holger

0 Fredrik K over 4 years ago in reply to HS FAE Germany

TI__Guru** 106705 points

Hi Holger,

Checking whether JTAG is on is done by polling AON_WUC:PWRSTAT.JTAG_PD_ON.

I am not sure exactly what register field the customer is looking at in their code.

Regards,
Fredrik

0 HS FAE Germany over 4 years ago in reply to Fredrik K

TI__Mastermind 30505 points

so there are 2 possibilities now

1) polling JTAG_PD_ON

2) HIB-Flag abfragen: bool HIB_Next = ((HWREG( AON_SYSCTL_BASE + 0xC) & 0x400) >> 10); => from forum

Right?

0 HS FAE Germany over 4 years ago in reply to HS FAE Germany

TI__Mastermind 30505 points

any answer?

0 Fredrik K over 4 years ago in reply to HS FAE Germany

TI__Guru** 106705 points

The answer is "yes".

BR,
Fredrik

0 HS FAE Germany over 4 years ago in reply to Fredrik K

TI__Mastermind 30505 points

is it accessing the same bit?

0 Fredrik K over 4 years ago in reply to HS FAE Germany

TI__Guru** 106705 points

Hi Holger,

If you take a look in the Technical Reference Manual for the CC1310, you will see that these are not accessing the same bit. For the purpose of detecting whether the JTAG domain has been activated and the HiB flag set erroneously during normal operation, they will both work.

Regards,
Fredrik