STM32F746ZET6 issue: Why overall process of the controller is delayed ?

[DK.4]

We are using the STM32F746ZET6 controller in our project.We are facing some issues, When we put the integration code to the controller we observed that the overall process of the controller is delayed.

One use case is integrated code: we run the PWM with 40Hz, In the working board that was fine. In the issue boards it runs with 0.5Hz.

We checked with external 24MHz clock and internal clock the same issue we observed in some of the boards we have, but the same code is working fine in some boards.

We are seeing the same issue in multiple boards. Compared with both the boards (Working and Non working) the clock, Reset and Power are good.

While we were putting the simple code to the device (44KB) the problem did not occur. While going with the integrated code (434KB) we are facing the issue.

Note: The same integrated code(434KB) is working fine in some boards we tried coding with multiple times no issue is found in that board. 

[TDK]

Doesn't really make sense that some boards work and some don't with identical firmware. Check hardware issues, solder bridges, power rails. Perhaps the HSE silently fails to initialize. You could also inspect the registers of the non-working board to find the issue.

[Tesla DeLorean]

Sounds like someone needs to debug the software if the hardware is good​.

All kinds of latent software issues can be caused by slight timing variations, or memory not being initialized consistently.

Instrument your code until you can identify different flow and behaviour between the units. If you have tracing or profiling hardware, break that out.​

Your post really doesn't identify a particular cause.​ Not sure what you're looking for here.