H View Labs Announces LabHSM - a New LabVIEW Toolkit for Developing Non-Trivial Event-Driven Applications

  • December 06, 2004
  • News
Most of the systems application programmers deal with today are reactive. It means that their primary function is constant interaction with their environment by sending and receiving events. But most likely, they can have something happening inside them too, even when they are not processing messages received from outside. So, such systems have to continuosly react to external and internal stimuli. Right? Moreover, most likely, they consist of subsystems that are reactive too and, in turn, can have their own "life", to an extent independent from other parts (with which they still communicate, of course). Reactive (event-driven) systems are more naturally modeled with active objects. So, why then should we try to model and code them with GOOP and its passive ("dead"!) objects?"Flat" State Machines have been known for decades to have severe limitations. It's been more than 20 years since Dr. Harel invented Hierarchical State Machines (statecharts) to fight those limitations. Then why does NI still tout the same old good Moore FSM as the ultimate tool for event-driven programming in LabVIEW in its $995 State Diagram KIt?The LabHSM toolkit we are happy to present, makes it possible to easily create and then maintain complex event-driven applications in LabVIEW as a collection of HSM-driven active object VIs using a higher level of abstraction and agile software development methodologies. These active object VIs are created based on a universal Hierarchical State Machine ( HSM or statechart )template. So. all your code lookssimilar regardless of its functionality!We all love just jump to code, right? However, to be good boys, we need to do design first. Then implement it in code. If the logic is modified we need to redo the design first and then redo the code. When using LabHSM where behavior information is abstracted into a separate HSM data file editable with a supplied editor, there is no need for coding separate from design any more. The modified behavior becomescode automatically as soon as the HSM file is saved. Design is code!The implementation basically follows Dr. Samek's Quantum Programming paradigm. (see www.quantum-leaps.com). However, as already mentioned, LabHSM stores the behavior information in a file separate from the code itself. It also adds state dependent priorities to events, a separate queue for public events/messages, and, of course, some LabVIEW specific code like capturing front panel user events and putting them into the private Events queue. Communication and instantiation functions are also rather specific for LabVIEW.It is available for UNLIMITED PERIOD trial. Please visit www.labhsm.com for details. The site also contains references which you may want to check to learn more about hierarchical state machines and active object computing.Use this link to buy LabHSM Developer's License and save $60.00 USDUse this link to buy LabHSM for Run-time License and save $60.00 USDFor more information please contact:H View Labs9 Tanbark Circuit, Suite 2050Werrington Downs, NSW 2747Australiawww.labhsm.cominfo@labhsm.comUS Toll-Free Phone/Fax: 877-570-8684

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