CSSequencer Proposed Solution

The following class descriptions represent a first design approach for the CSSequencer package:

• CSListObj
  • Handles hierarchical structured list elements
  • Each list element defines, for example, one test step
  • List Elements could also handle sequences instead of single test steps
  • List Elements can be restructured for editing the order of sequential execution
• CSSeqExec
  • Querries CSListObj for Test Steps
  • Triggers Test Step and waits for result
  • Controls order of execution depending on test step result:
    • loops, break conditions and branches (structural elements)
    • editable via scripting tool
  • Easy to replace sequence of test steps by connecting CSSeqExec to another List object
• CSProxy
  • locks and unlocks any BaseProcess object for exclusive access via event – driven communication
  • avoids the interaction of parallel running sequencers that use the same device object
• CSDuT (Device under Test)
  • Each HW device that belongs to a single test step can be connected additionally to a DUT object:
    • Defining sequence of events for device object
    • Using CSProxy class for locking mechanism
    • Defining test Input and expected reaction
    • Defining ways for analysis
    • Defining conditions for test result (failed/successful)
• class diagramm:
  

more detailled class definitions

• CSDuT
  • serves as parent class for any DuT object
  • inludes the following functionality for the developer
    • classname.ProcStimulate.vi: defines how to stimulate the device object
      • data types of data to sent
    • classname.ProcRespond.vi: defines how to work its respond
      • data types of received data
      • next step in sequence
      • finish test if desired
      • decision for test result (successful or failed?)
    • classname.ProcSequence.vi: defines sequence
      • multiple sequences possible
      • groups events into event arrays
      • defines order of execution for event arrays
      • loop function for event array
      • defines call type for each event
  • handles locking mechanism (CSProxy)

• 

After discussing several possible test scenarios during the last meetings a first approach concerning the design of the CSSequencer basic classes has been accomplished. The following UML diagramms should present the outcome of these discussions.

• interface between any device process and CSSequencer classes:
  

• multiple DuTs in one elementary sequence:
  

• USB Interface Test Scenario:
  

-- MaximilianKugler - 23 Mar 2006