Simulink const block referencing changing variable doesn't update during simulation

2 次查看（过去 30 天）
Istvan
Istvan 2014-7-7
评论： Istvan 2014-7-7
In my Simulink diagram, I have a const block that references a global variable (lets call it myVar). I have an event handler that is called every clock tick (looks for a change in a clock block's output). That handler looks like this:
function speedRampUpUTManager(block, eventdata)
simTime = block.OutputPort(1).Data;
global myVar;
if(simTime == 10)
myVar = 1500; //myVar is initialized to 1700
end
disp('myVar:');
disp(myVar);
end
Sure enough, during a simulation the disp shows 1700, then starts showing 1500. However, when I look at the scope attached to the const block with the Simulation Data Inspector, the value is 1700 the whole time.
My const block has the following settings:
  • Const Value: myVar
  • Interpret vector parameters as 1-D: unchecked
  • Sampling mode: Sample Based
  • Sample Time: -1
Perhaps one workaround might be:
set_param(constBlock, 'Value', 'myVar')
But I'd like to avoid that if possible.
Regards, Istvan.

请先登录，再回答此问题。

采纳的回答

C.J. Harris
C.J. Harris 2014-7-7
Unfortunately unless you call 'set_param' the value of the variable will not be re-evaluated. Therefore calling 'set_param' is the way to do this. I would however recommend you find a way of doing this in Simulink instead, either via switches, or Stateflow if necessary, thereby avoiding the need for an event handler altogether.
See also: How Do I Change a Block Parameter Based on the Output of Another Block?
  3 个评论
显示 1更早的评论
C.J. Harris
C.J. Harris 2014-7-7
I've not actually tried this, so I'm just speculating here, by maybe it is necessary to also call the 'update' method:
set_param(bdroot,'SimulationCommand','update')
Istvan
Istvan 2014-7-7
Unfortunately, that didn't work. Since this isn't related to the initial question, so I posted a new one here .

请先登录，再进行评论。

更多回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Simulink Functions 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by