Why does my Nios II software crash unexpectedly when using MicroC/OS-II with Vectored Interrupt Controller(VIC) ?

Description

The Vectored Interrupt Controller (VIC) is not currently supported for use with MicroC/OS-II  based systems.  The Nios II MicroC/OS-II multitasking kernel does not support the shadow register set switching required for VIC, and will cause unexpected software behaviour.

Resolution

To workaround this limitation, the Internal Internal Controller (IIC) should be used for MicroC/OS-II based Nios II designs.

This limitation is scheduled to be addressed in a future release of Nios II.