Gain block ignored :

I have a Simulink model with a gain block that has a ToWorkspace before and after, yet the ToWorkspace traces are identical even though the gain has been set to 64, any ideas what may be causing this?

[Jim Riggs]

Need more information. What are the settings in each "To Workspace" block?

Variable Name

Data limit

Decimation

Save Format

Sample time

Answer 1

[Fangjun Jiang]

The input value to the Gain block is constant zero? Need more info to see the problem.

[Doug Bell]

thanks Fangjun - it needed a convert datatype block prior to the gain block , it was a Boolean flag toggling between 0 & 1, then multiplied by a power of two, converting to a float before the gain seems to have fixed it

[Fangjun Jiang]

Without the data type conversion block, the output should still be 64 when the input is boolean true, right?

Answer 2

[Doug Bell]

that was the assumption but it took the datatype conversion block to get what I wanted

Answer 3

[youjarr]

Hey Guys,

I have an similiar issue.

I have an Signal which is not 0. Then I put an 0 Gain to it... with an parameter which is read from the base workspace.

That value is 0 so I would thing the output of the Signal*0 is 0... but it isn´t it has the value of the signal.

But when I write the 0 directly into the gain hen it works and the output is 0.

The datatype conversion has no effect... .

[Fangjun Jiang]

You are saying that you have a Gain block, its "Gain Value" is a parameter from the base workspace, the value of the parameter is 0, yet, the output of the Gain block is non-zero.

It is strange. I would double check the value of the parameter, the name of the parameter, lower case, upper case, etc.

There is a chance, that there is a parameter with the same name, in the model workspace, its value is non-zero. The variable in the model workspace takes precedent over the base workspace, if their names are the same.

[youjarr]

You were right. Somehow I saved a value in my model workspace.

Thank you very much.

Have a nice weekend.