simulate a variable from 0 to 255 in simulink

I need to simulate a variable from 0 to 255. And after they return from 255 to 0 and so continuously, all in simulink. I need this to simulate a variable "pv" signal processing (level control)

thanks

[Fangjun Jiang]

You want the pv value increase by 1 from 0 to 255 and then come back. What is the time vector? Every 1 second change from 1 to 2, or every 1ms from 1 to 2?

Answer 1

[C.J. Harris]

This setup should do what you need:

Create a constant (1 for example), feed that into an integrator block, then feed that into the 'mathematical function' block (set to 'mod'), and set the second input to 255.

Increasing or decreasing the first variable will control how fast your variable counts up.

[Felipe Arriagada]

I get an error.

Warning: Using a default value of 0.2 for maximum step size. The simulation step size will be equal

to or less than this value. You can disable this diagnostic by setting 'Automatic solver parameter

selection' diagnostic to 'none' in the Diagnostics page of the configuration parameters dialog

This is the setup? http://felipedream.zobyhost.com/cunting.jpg

[C.J. Harris]

Your image doesn't work, but all that warning is saying is that if you are using a fixed step solver your simulation time should be a multiple of your step time.