Unable to Arm PX4 Autopilot from pwm_output

Hi. Snapshot of the Simulink Model and QgroundControl, i am about to discuss is attached with this.

In Model_Snapshot when i set Arm = 1 in pwm-output0 block in simulink, the actuator/servo connected to the I/O PWM OUT of Pixhwak Board move on RC Control Commmands but the Arming status of actuator_armed uORB_Read block remains zero. Likewise, when i opened the QGroundControl App the arming staus was "Ready to Fly".

But my assumtion is that when i set Arm = 1 in pwm-output0 block in simulink, the arming status i am reading from actuator_armed uORB_Read block should change to 1 and same should be displayed in QGroundControl.

My Question is why Arming status of actuator_armed uORB_Read and Qground Control does not change to Arm on setting the Arm = 1 in pwm-output0 block in simulink ?