Dap: Error connecting to the target: (Error -241 @ 0x0)

Hello Stelios,

Can you cut and paste the output from the "Test Connection" operation into a post so I can look at it?

Hello Chuck,

I attach it.  I tried new projects, different projects that were loaded before, but no luck.

Regards

0602.testConnection.txt

Hi Stelios,

The output file looks fine which tells me there isn't anything wrong with the setup in CCS and the emulator can access the scan chains.

Can you describe what code was running in the device when you unplugged it? Was this the CCM error forcing code from your earlier post? i.e., with the while(1) loop around the CCM error forcing routine?

Chuck,

I was testing the CCM, but as you suggested I was not doing it in a while loop. Actually I created one project, when pushing the programmable button, the CCM was producing the error, with a second push clear the error. Actually it was working fine. When I unplugged the launchpad from the power supply to demonstrate it to my colleagues and tried to plug it in again, this problem occurred. Could the board be damaged?

Regards

Hi Stelios,

I did some checking on the tools forum and found a couple of posts where they had the same error.

e2e.ti.com/.../414422
e2e.ti.com/.../336829

Can you put a scope on your OSCIN or crystal to make sure you are getting a clock input?

Hello Chuck,

I will check it on Monday that I will have an available scope. In the meantime, if you think of any other possible solution, please inform me.

(By the way, I did not verify your answer in the topic for CCM yet, because I am planning to extend our discussion on that). :-)


Regards,
Stelios

Hi Stelios,

No issue. Have a great weekend and we'll pick it up again on Monday!!

Hello Chuck,


My clock looks to be ok. I get a normal waveform on my scope. What I noticed and seems weird is that I am getting 0.5V to the B17 pin (WARM_RSTn) with a voltmeter. Could this be a problem?

Any further suggestions?

Kind regards,
Stelios

Hi Stelios,

0.5V on nRST does not seem normal. It would be seen as a low. Also, given you are mearuring with voltmeter, it may be toggling between asserted and de-asserted. Is it possible to check this signal with a scope to get a better picture of what is happening?

Also, you might try the trick of holding reset during the connect sequence and releasing just as it is trying to connect. If there is software causing the MCU to continuously reset, you can try and catch it during the startup before the error occurs that is causing the resets. This will allow the debugger to halt the core before it starts executing. At this point you could erase the image.

Hello Chuck,

I will give it a try tomorrow, but I am a bit pessimistic about this solution, as my software was running without any problem, until the moment that I unplugged the power supply. Is it something that I can check to see if my board is electrically damaged? To add an observation, touching the MCU now, I noticed that it is warm enough!!! I am not sure if it is warmer than the normal, but I give you as much details I can, to find a solution to this frustrating problem.

Regards,
Stelios

Hello again,

Something holds my NRST line low. When I press the button it goes high for a moment and then low again. So I assume the button is not the problem. What could I check?

Kind regards,
Stelios

I attach the code that ran for last time, but I do not think that my code was the problem.

Regards,

Stelios

7043.LockstepTest.zip

Hi Stelios,

I am looking into your problem a bit further and discussing with my colleagues if there is anything additional that we can look at in trying to get to the bottom of this issue.

In the meantime, is the short time that nRST is released after pressing the reset button long enough that you might be able to catch it while trying to connect? If there happens to be something in the code that is causing this, the debugger would halt the core and you could gain control with CCS. After that you could potentially erase the device. If it is a HW issue, this wouldn't really help much but maybe worth a try with either CCS or Uniflash.

Second, could you check the pullup on nRST to make sure it isn't damaged in some way? The resistor is a 10Kohm pullup (R268).

Also, the nRST signal is passed through a buffer (U2) before reaching the connector (J11) on the bottom of the board. It might be that this buffer is damaged in some way pulling the signal low. Can you check the nRST signal at pin2 of the that device? If possible, see if it has any impact to lift pin2 to disconnect it from the MCU.

Apologies for the difficulties you are having.

Hello Chuck,

I tried the trick of releasing the Reset button and try to erase flash around a 1000 times and it did not work. Either I am unlucky or it does not work for me. :-) The resistor R268 looks fine and the buffer U2 as well. I desoldered the resistor R134 to isolate it and nothing changed. If you thought about anything else that I could try, please inform me.

I have a second same evaluation board. Could you please check my code that I attached before, to make sure that this is not the problem? I want to load this code to the second board, but I have to make sure that I will not damage it too.

I will write to the other post soon regarding our CCM-R4F discussion.

Thanks and regards,
Stelios