You should be able to retrieve the specific model guide, by using the F1 key (=help) when the (PI) control block is selected on the canvas.
Anyway:
[list]
[li]Y_S = set-point[/li]
[li]K_P = gain[/li]
[li]T_I = time constant [d][/li]
[li]u_0, u_Min, u_Max = no error, minimum and maximum action[/li]
[/list]
Remark: units for Y_S, u_0, u_Min, u_Max, K_P depend on the controlled variable