TMS570LC4357: Continuation: Memory test fails when run in standalone mode

Gobind Singh1

Intellectual 640 points

Part Number: TMS570LC4357

Tool/software:

Hi Jagadish,

This is the continuation of the linked post. I have opened a new one because the previous one was locked.

From your last message on the linked post:

>>Can you please also try to include memInit before performing RAM testings?

Yes. The memory tests work OK if I include memInit both before and after the memory tests.

But this does not solve the problem completely because:

1. If I need to do some startup tests, lets consider watchdog integrity test, I need to preserve the contents of the memory after the reset to compare, otherwise I cannot conclude if the integrity test has passed or not. I cannot use the memInit() because it clears the memory. And we have seen that the whole RAM is written with garbage data when this problem occurs.

2. We are not even sure why this problem is happening. Do you atleast agree that it is a problem with the microcontroller?

Thank you.

Gobind Singh

6 months ago

0 jagadish gundavarapu 6 months ago

TI__Guru 69891 points

Hi Gobind Singh,

It is not controller problem,

My understanding is that we should never access the RAM memory without calling _memInit_ function. This is because,

to understand it refer below highlighted sentences in the TRM:

So, without hardware initializations your RAM will be full of single and double bit ECC errors. Just like as mentioned in below thread:

(15) Compiler/TMS570LS1227: Retention RAM data after software reset. - Arm-based microcontrollers forum - Arm-based microcontrollers - TI E2E support forums

So, if you are trying to access these corrupted RAM then it will automatically perform single bit error corrects (that means your written data might get changed), that means if you try to compare the data then the data mismatch will happen, and RAM testing's will get fail.

So, it is always good to do RAM testing's after doing _memInit_.

--
Thanks & regards,
Jagadish.

0 Gobind Singh1 6 months ago in reply to jagadish gundavarapu

Intellectual 640 points

Ok, thanks for the respnse Jagadish. So as I understand, is it correct that we cannot do a test like watchdog integrity test as mentioned in the first message of this post? And if we have to do it, it will not be a simple task - as described in the linked post that you shared?

And is there any other/simpler way to test the integrity of the internal watchdog?

Thank you.

Gobind Singh

0 jagadish gundavarapu 3 months ago in reply to Gobind Singh1

TI__Guru 69891 points

Hi Gobind Singh,

The reason for unlocking this thread is that it is not closed properly from TI side, so i unlocked it again.

Gobind Singh1 said:
Ok, thanks for the respnse Jagadish. So as I understand, is it correct that we cannot do a test like watchdog integrity test as mentioned in the first message of this post? And if we have to do it, it will not be a simple task - as described in the linked post that you shared?

You are correct.

Gobind Singh1 said:
And is there any other/simpler way to test the integrity of the internal watchdog?

The only way i think is that using the flash memory, maybe you can write into the flash bank-7 of the device.

--
Thanks & regards,
Jagadish.