Integrating xilinx uartlite driver in simulink

Hi

I am trying to integrate the xilinx axi4 uartlite driver into simulink. I have tested the completed code and example on xilinx SDK and it worked well. However , despite that i was able to compile the code and generate the arm binaties , i am getting error in connecting to external mode.

please note i am using zed board and code is compiled for zynq. moreover the builtbin examples which use external mode are working fine . one more thing , my device driver code is interrupt driven .

Any help would be greatly appreciated .

Saqib Ali