I am running the latest MQX (4.1.1) on a K60 Tower BSP derivative platform.
If I start RTCS before adding an external memory pool (with _mem_extend() ) everything is fine.
If I start RTCS after adding an external memory pool I can't ping or do a socket connection to the device, though DHCP client is able to get an address.
My external memory is fine. It's is used for many other things. In either case no MQX errors are reported, memory, stacks, tasks, etc.
Could this be some cache coherency issues (DMA related) in RTCS? External memory is in a cache-able region.