I am having an issue with my UART on a SAM7X256. I have two projects, both of which just send test patterns to a LCD module over the UART (polled, no ISRs).

One project is just timed off the PIT and is a no-frills project. The communication works great.

The other project is based on FreeRTOS, and it took the LCD code from the first project and just made minor changes to make it OS-compatible. But I cannot get the UART to transmit properly on this project.

I have taken register dumps of the UART, PMC and system registers to see if any settings are different, and they are all the same. I can see in debugging that all the code is being called as it should. But the UART is not having it.

Has anybody run into this before?

All of my debugging tricks are not working with this issue. I have performed complete register dumps with working vs non-working systems and found no culprit. I did a sequential build from my working version into my non-working version and eliminated some possibilities but still couldn't pin down when the UART would stop working.

The only thing that sticks out at me is the peripheral reset, but the documentation only talks a little about it. Is there any way of checking whether a peripheral is being held in reset? What could hold a peripheral in reset besides the watchdog?

Hi ,
I have worked on UART and FreeRTOS It's working fine. Can Send me your code So I can check it out.