Working models, important process settings

Each new diagram has a block with the name Process. This block cannot be removed. This is a block responsible for all the process’s settings. The block has a few inputs:

• Stop - if it becomes from low to hight level, the process will be stopped.
  
• StopAndClose - if it becomes from low to hight level, the process will be stopped and application AltonaLab will be closed;
  
  
• DoNotStop - if this input is in hight level and the user tryes to stop the process, the application will show a message box with message, that the process can't be stopped. The text of the message can be gotten from input DoNotStopMessage. If this input is not connected, the message is defaul.
  
• DoNotStopMessage - the message which appears if the input DoNotStop is connected, is in hight level and the user tryes to stop the process.

Parameters of the block are:

• TimeProcess - the time of the process in seconds. After start of process, when the time expires, the process stops automatically.
  
• DiscreteTime - this is the minimal time quantity of the process and is important value for blocks like integrator, differentiator, regulators etc:
  

http://en.wikipedia.org/wiki/Discrete-time_signal

• RunAlways - if this parameter is checked, the process continues up to infinity without care of parameter TimeProcess. Process can be stopped only manually.
  
   

The parameters of the block allow the management of several kinds of processes:

Process modeling

• This is a method in which the visualized values are not real time. The process stops automatically when its time expires.  AltonaLab is a fast-acting software and even if the process time is long (minutes or hours) it can be calculated and visualized in a few seconds. In this kind of process, it is not recommended the computer to be connected with the hardware inputs/outputs of a real object. The computer’s processor will be loaded up to 100%. Parameters of the block have to be: TimeProcess – the process’s time in seconds, the process will stop when this time expired, DiscreteTime – this is the discrete time in seconds, RunAlways - not checked.

For example, DiscreteTime=0.001 sec is equal to 1000Hz discrete frequency, TimeProcess=10sec, RunAlways=false;

Controlling fast processes in real time

• The process has to be started for a limited amount of time. If I/O hardware is fast, the system can make thousands of readings per second. Every combination of computer, I/O hardware and different number of blocks in a diagram, gives different discrete time of the process. This is the reason why you have to experiment to determine the discrete time. Start the process for a few seconds and then check the information for the finished process in the blue area on the right side of AltonaLab. The resulting discrete time is written after the text Real Time dt: You have to input this time as a parameter of the Process block – DiscreteTime. The TimeProcess parameter is processing time needed in sec. RunAlways=false. The processor will be loaded up to 100%.

Controlling slow processes in real time and Home automation

• In this case, the process time is infinity. Once the process is started it can be stopped only with the Stop button. Process parameters are: TimeProcess – has no meaning in this case, DiscreteTime has to be larger than 0.05 sec, which will unload the processor, RunAlways - checked.

If the DiscreteTime is 0.2sec, this means the entire diagram will be calculated 5 times per second. The processor will be lightly loaded, but it is possible if the user push the button from diagram, the process result to be delayed. In this case we can decrease the discrete time to 0.1 .. 0.05 sec.