MPC5748G is always in reset

[1134325419]

When the MPC5748G is powered on, the D1 LED (reset LED)of the board is always on, and the RST pin signal of the MCU is measured with an oscilloscope as shown in the attachment "RST signal".

There is a window poped up when I debugged the MPC5748G,as shown in the attachment "Pop-up window".

I tried every means to connect to MPC5748G with PROGPPCNEXUS, but even though it was connected, only RE Reset chip can be selected,as shown in the attachment "PROGPPCNEXUS Interface ". After resetting many times, it looks like this.

How can I restore the MPC5748G?

[peter_vranken]

P.S. The paths stated in the command lines depend on the revision/patch level of the Design Studio and will most likely need an according modification. Just look at your installation directory tree and modify them

[1134325419]

I tried to burn the program quickly after power-on. My board can burn the program to 98%, but it just stuck at 98% and cannot load to 100%. Can this problem be solved by the way you said? The attachment is the program burned to 98% of the pictures .

For the specific situation, you can read my comment below.

[peter_vranken]

Sorry, I can't answer that question. I remember very well that I saw the message "Cannot enter background mode", too, as long as I didn't get a connection with the debugger and of course because of the reset escalation. You need to manage getting the connection before the fifteen resets. (Which is difficult to achieve with the normally used, slowly reacting GUI elements.) In the debugger client you see very well if you are connected. Only if you are connected then you can take the next steps, in particular flashing another SW with the load command. Before, it'll fail.

Peter

[peter_vranken]

Hi,

When starting with the DEVKIT-MPC5748G I'd had the exactly same problem. I'd then elaborated a recovery strategy at https://community.nxp.com/t5/MPC5xxx/MPC5748G-Cannot-attached-JTAG-after-erase-all/m-p/617384#M5278 . It's all about hitting the right timing. You need to get a debugger connection within the 300ms. This is difficult using the standard user interface elements, but there are ways to do. Please refer to the other post.

Peter

[lukaszadrapa]

Hi,

this is caused by reset escalation feature of the microcontroller. See this thread, for example:

https://community.nxp.com/t5/MPC5xxx/MPC5748G-Reset-escalation-PEMicro-Multilink-FX/m-p/951221

In short, turn the power off, press and hold the reset button, turn the power on. Now release the reset button and press "Connect" within 300ms. Maybe a couple of trials will be needed but it's possible.

Then program application which disables watchdog right after reset (or which re-configures and refreshes the watchdog) and it will work next time without this procedure.

Regards,

Lukas

[1134325419]

Thank you very much for your reply.
According to your suggestion, I burned a program to the board, but now there is another problem: the program has been burned to 98% and it doesn't move, as shown in the attached picture "Burned to 98%". I waited for an hour and it was still 98%.

I stopped the current debugging operation, and the board is still in the reset state after power-on again.

I followed this operation several times, and every time I debugged it was stuck at 98%. After waiting for a long time, it was not loaded to 100%.

After reading the relevant solutions in the community, I use PROGPPCNEXUS to operate MPC5748G. But when I connect to MPC5748G with PROGPPCNEXUS, I find "Cannot enter background mode", as shown in the picture "PROGPPCNEXUS Interface" in the attachment. By the way, during this process of connecting to MPC5748G, a window will pop up for every operation, such as the attached picture "Pop-up window".

Is there a way to solve this problem?