Lab 5 – Serial Poll Bytes - Device Status

 I. Objective:

To give the student a lesson in the use of serial poll bytes and how to control use serial poll bytes and Device status to monitor instrument events and status.

II. Procedure:

In this lab, you will monitor the status of the Lock-in Amplifier and report the status to the User using a VI. The VI must

  1. Monitor the Status byte and display this information on the VI front panel as a series of LED lights. You are REQUIRED to use either an ARRAY or CLUSTER data format for the status byte.
  2. As a separate monitor, display a boolean indicator (LED is fine) which indicates if the Lockin is overloaded or unlocked. (For LOCK-IN operation, these are the most important status conditions.)
  3. In your implementation of the reading of the status, think about how often and where in the VI's logic sequence you should check the status of the instrument. Clearly, checking it too often slows down the VI execution while not checking it often enough may result in missing a critical instrument error.

Additional information and a copy of this lab is located at:

http://web.njit.edu/~gnita/VI/OPSE310/OPSE310lab_5.htm

Submit the created VI or VIs by attaching them to an e-mail document that contains the answers to the discussion questions below. (Note that you can either attach the VI or zip the VIs by using WinZIP). E-mail the answers to the discussion questions and the VI or VIs to:

gnita@njit.edu

III. Discussion:

  1. In a more sophisticated version of this lab, if an OVERLOAD status condition is detected by the VI, what action should the VI take? Eg. warn the user? Change the sensitivity settings? Change the time constants?
  2. In this lab, you were required to use an ARRAY or CLUSTER data structure for the status byte. Is there an advantage to using this data structure for the status byte rather than using 8 separate boolean structures?