Need help with transfer function of Discrete PI controller!

when we design our own PI controller, it uses a transfer function block. I am given with a transfer function HMWF0(z) = 1/n*((1-r^n*z^-n)/(1-r*z^-1)). But when we select PID control block from Discrete library of simulink and changes it to PI controller, I can't change the transfer function to given function. Should I pass the output of PI Block to a transfer function block with given function? If so, what should be the parameters of PI controller, such as discrete time settings(integrator type)?

This is the system that I am working on simulink!