I want to use the Debug Unit as a menu based debug shell and I have some problems with receiving characters and passing them to the corresponding task.
I know that DBGU and PIT (for tick generating) are sharing the same interrupt and I can toggle a led on character receive but more interesting for me is forwarding the received character preferred with a queue. But as soon as I call a normal function (not inline as for now) the systems seems to hang up.
Now my real questions:
- Why is contect saving and restoring used for the tick increment instead of isr enter and exit
- and how can I do function calls from this system interrupt?