MC9212XEQ512 - SCI does not work after COP reset

[JohnBarber]

Hi,

I'm using a MC9212XEQ512 and performs a COP reset by writing to the ARMCOP register:

/* Activate watchdog */COPCTL = 0x07;/* Write wrong value to COP-timer (will cause a reset) */ARMCOP = 0xFF;

After reset, the SCI is configured. But nothing is transmitted when I try to.

But if I connect my P&E debugger, it works. I.e the SCI transmission is performed.

Can someone explain this?

/John

[JohnBarber]

Edit:

I can verify that the SCI is configured correct. I can perform a transmission by directly writing to the data register.

But transmission using TX interrupt does not work without the debugger connected.

/John

[J2MEJediMaster]

It is possible that you are failing to initialize something that the interrupt hander requires, and the debugger happens to initialize this properly when you are using it. Have you tried one of the example code programs with an interrupt handler and see if it works? If it does, you can compare the example code to your own to see if you can spot the problem.

---Tom

[JohnBarber]

Hi,

the situation is like this:

I have a bootloader that sets up the interupts. This works fine. The bootloader starts executing and I download an application. The application is then started and works fine. Interrupts works too. From the application I then perform a watchdog reset and the bootloader starts again. This time the SCI interupts are note working when the debugger is disconnected. If I have the debugger connected everything works.

This is strange.

/John

[J2MEJediMaster]

There have been similar situations like yourt reported on these boards. Take a look at this forum https://community.freescale.com/message/56738#56738 and see if it might help you.

---Tom