Unlock Problem TM4C123G

Hi Deep,

Maybe your Launchpad JTAG is not locked.

Using LM Flash Programmer, Erase Entire Flash of your Tiva MCU. Then load a known working example program like "blinky". If the example program works, you have recovered your Tiva Launchpad.

- kel

I cant able to erase flash. Showing this error : "Unable to find a target."

Hello Deep,

What the Windows Device Manager show?

Regards
Amit

Windows device manager dont show device and icdi com port.

Hello Deep,

Snapshot please.

Regards
Amit

Device Manager screenshot when launchpad id attached.

Error during unlocking.

 

Configurations in LM Flash Programmer.

 

Hello Deep

The fact that the ICDI or for that matter the Stellaris debugger does not show up in the device manager could mean that the ICDI emulation TM4C123 is not working. I think you may have accidentally programmed the ICDI chip itself. Did you happen to change the switch on the board?

Regards
Amit

Hello Amit,
Sorry i dont get you.what do you mean by
Did you happen to change the switch on the board?

Hello Deep,

There is a switch right next to the USB connector which you use to power and debug the device.

Regards
Amit

Ya there is one switch. What i have to do with this switch??
When i change the switch state from device to debug green led turns on but device manager dosent showing icdi drivers.

Hello Deep

The switch has to be in debug state by default for you to be able to use the ICDI to debug the main TM4C123 device. Why was the switch kept in Device position? Is there any change in the Device Manager when the board is unplugged and plugged?

Regards
Amit

Ya switch is in debug state. And there is no change in device manager when i plug or unplug the cable.

So it means that my launchpad is damaged. I cannot use it now.
I have to purchase a new one.

Hello Deep,

Not damaged but "costly" overwritten.

Regards
Amit

Ya..
By the way.. Thank you.

Hello Amit,

Two days ago (March 12, 2016), I posted my question "I cannot do anything with my Tiva C-Series LaunchPad"
I'm 100% sure that my problem is exactly like Deep's. So, what do you mean by "J5 connector on the bttom of the board (AFAIK)"?

Would you mind telling me more about this solution?

Thanks a lot!

Hello Phi

And in that post, I think I had asked you to try Unlock Sequence as well. However it later turned out that for some reason the ICDI was not being detected. Without ICDI the unlock sequence will not work.

Regards
Amit

Amit,

I'm glad you have already tried your best to help me recover my LaunchPad. Now I can see, this problem is similar to leaving the key inside the room and lock the door.... :)

New LaunchPad!!!!

Sincerely thanks, Amit!

Phi

Hello Phi,

It might not hurt to try it on another PC!!!

Regards
Amit

Hello Amit,

I tried it, but it is dead -__-

Thank you very much :)
Phi

Board  was working fine.

Today I programmed it twice. Next time when I tried to reprogram it gave me error that JTAG initiallization failed.

So I thought it may locked. So I tried to unlock it by LMFLASH. But there also it is showing Failed to unlock device.

What to do?

Regards,

Krishnat

I tried o another PC,  unlock process succeeded.

but still I am getting JTAG error.

If I go for Hardware reset. It shows  "can't find the target device"

What to do?

 

switch position is also correct.

Sorry I forgot to mention board I am using.
Its Ek-TM4C123GXL LAUNCHPAD.
As shown in pic.

HI amit,

previously i post about board is not detecting, I send u pics regarding that also. my problem was little different than what this says.. So I couldn't continued and thought my board is dead and ordered 2 new board. But one of them is dead now. Symptoms are same as this thread. I have posted query about that.. please give me solution. with that j5 connector is it possible to recover? if u have any info. how to do recovery with that j5 please share.. waiting for reply. 

     

I happened to brick my TM4C123G board the same way due to some carelessness on my part when setting up my development environment on a new PC. I later realized that I used version 1381 (older version) of the LMFlash tool which doesn't even support the TM4C123G board. Sigh..... ordered a new board.