Problem facing in PID control design (closed loop)

[cyrus_sun]

Hi, i have facing some problem during i upgrade a project. This project is an opened loop system, it only achieved up to controlling the speed of motor, detecting the speed of motor, and switching the direction of motor while controlling the motor (This motor is a 12 VDC motor).
 
In order to improve the project, closed-loop dc motor control system will be implemented to correct the error of the motor's speed and maintaining the speed for the initial setting. I would like to use PID control method to do the closed loop system.
 
I already installed the PID toolkit V8.2 and control design toolkit V2.1.2, and i'm using DAQ usb 6221, LabVIEW 8.5 

Below is my problem.

http://img177.imageshack.us/my.php?image=howtocreatethesetpointnx2.jpg

question: 1. How to generate a icon for set point? my setpoint is duty cycle...

                2. How to feedback the output duty cycle to summing junction?

below this is my basic concept

http://img237.imageshack.us/my.php?image=closedloopbz5.jpg

Problem 2:

http://img357.imageshack.us/my.php?image=problem1yk2.jpg

question: Why PID toolkit icon cannot wire to cd series.vi? 

Below is my original program...

http://rapidshare.com/files/140538836/pwm_generate-final_PSMII.vi.html

[Vivek_N]

Hello cyrus_sun,

To answer your second question, the PID VIs are not meant to be used with the Control Design VIs in this manner. You are currently trying to wire the 'double' output from the PID VI to a typedef cluster input (the model) on the CD Series VI. The CD Construct PID Model VI should serve this purpose instead.

I did not understand the first part of your question. Could you please elaborate on what you want to do? 

Thanks,