- Parallel To Serial Converter
- Serial To Parallel Converter Verilog Code
- Parallel To Serial Converter Ic
Welcome to the MATLAB Central Simulink blog! The purpose of this blog is twofold: First, I want to share Simulink tips andtricks that I've learned over the years. At the same time, I hope to learn from you about your experiences with Simulink.Where is it good? How can we improve it?I've been using Simulink for 9 years, first as a member of our technical support team, and then as a trainer.
I still rememberwhen I first learned about the power of Simulink as a newly hired support engineer back in 1998. During a training class Isaw differential equations drawn on a whiteboard and then simulated with a few clicks of the mouse. I got excited by how clearlyit all worked. Simulink provided me with a framework for thinking about systems and the relationships between their basiccomponents.Of course, Simulink is much more than a simple tool for solving differential equations. It has a richness and depth that willgive me plenty of material to draw on.
What kind of topics can you expect to read about here? We'll talk about applicationsof Simulink in controls, signal processing and communications system design. With your help, we'll talk about how Simulinkis used in areas I don't even know about yet. We'll talk about Model-Based Design in general, and we'll get a peek at someof the internal machinery of Simulink. I look forward to posts about all of these. solvers. sample times.
modeling. hacks. blocks. model reference. libraries. masking. custom codeAn example: batch simulationLet me start off with a specific example about running simulations.
Simulink models are built using block diagrams, and oncethey've been created most everyone runs them by clicking the run button on the toolbar.If you have to run a sweep of parameters you might change the parameter and then click run, change it again and click run.But if you have to run hundreds or thousands of simulations while modifying a parameter you will want to write a script forbatch simulation. You can run simulations directly from MATLAB with the sim command like so. t,x,y = sim(sys);This returns the root level outputs (y) and the internal states of the model (x) at each recorded time step (t). A batchscript might look like this:opensystem( 'vdpmu')muSweep =.5.1:1.5;for i = 1:length(muSweep)mu = muSweep(i);t,x,y = sim( 'vdpmu');plot(t,y); hold on;endtitle( 'VDP States for mu=.5 to 1.5')xlabel( 'Time'); legend( 'x1', 'x2')If you are already familiar with the sim command, then you probably know that some times you are only interested in the outputs (y) of the model, and not the states(x). For large models, or long simulations, those state variable outputs could be a waste of valuable memory. Using simset you can provide additional options to the sim command to specify that you only want time (t) and outputs (y).
The state variable returned from sim will be empty.t,x,y = sim( 'vdpmu',simset( 'OutputVariables', 'ty'));whos t x y Name Size Bytes Class Attributest 206x1 1648 doublex 0x0 0 doubley 206x2 3296 doubleYou can learn more about.What do you think?That's your first Simulink tip. Now it's your turn. What do you like about Simulink? What would you like to talk about infuture posts? Please leave a comment below.
I have learned from that t-shirts get comments on your blog, so I'll be randomly selecting five commenters on this post to receive a MathWorkst-shirt!Published with MATLAB® 7.5. Eric S.replied on: 1 of 123Hey Seth, congratulations on the new blog! Took a while to get the first one published;)For people unfamiliar with the interaction of Simulink and workspace variables, could you discuss how changing the variable 'mu' in the base MATLAB workspace ends up affecting the simulation?A convention that Loren uses that I appreciate is to hyperlink the first mention of any new function to its online documentation.
I nearly missed the link to SIM and SIMSET because it was located a long ways after you started talking about the functions.Cheers,Eric. Songreplied on: 8 of 123Hi Seth,I have just learned Simulink for two months and before I was alsways Matlab user. Recently I try to place my algorithm written in Matlab into Simulink because of its beautiful and clear organisation of blocks. Also it provides me a better examination of the interface signals and the real-time ability of the algorithm.
I am very excited about Simulink and also your new Blog, and hopefully it will also be useful like other Blogs in Matlab websites (like it from Doug) ^^best wishessong. Jeremyreplied on: 31 of 123Seth,What I am trying to do is have a simulation running for 10 seconds and get 5 seconds worth of data plotted, sampled from every second point. I don't want every second value to be zero. Thus if I attach a scope to the input it will have 10 seconds woth of data, but a scope attached to the output of the sampled data will have only 5 seconds worth of data on it. A decimate vector applcation would do it for me, but simulink seems to combine data well, but not strip data.Cheers,Jermy. Sethreplied on: 32 of 123@Tami - You have found a good place to ask questions, but I have to warn you that I might not have the answers.:-)You may want to post on, or if it is a technical support question.@Jeremy - If you are looking at the data, set your scope parameters so the Sampling Decimation is 2. Then you can just look at the decimated data.If you are trying to log data like that, try the To Workspace block.
It also has a decimation parameter. The other option is to change the sample time by 2. For this, a Rate Transition block might be your best bet. Sethreplied on: 37 of 123@Wei - Thanks for pointing out that MATLAB Tip.
Doug and Loren will be pleased that we can learn MATLAB while reading a Simulink blog.If you would like to include HTML in your comments, you may, however some types of markup may be held for moderation, and it will not display immediately. You could also with the images you would included in your comment, and I can add them later.@Jeremy - Could you write out the expression for the type of averaging you are doing? Do you mean something like this:Y(n) = (U(n-2)+U(n-1)+U(n))/3. Ronreplied on: 44 of 123Hi Seth,I have a Simulink/xPC target question.
I have a Simulink controller model and would like to bring data in from a CAN link. I would like to put this data into an array, (a circular buffer), and then in my controller I would like to grab elements of the array and perform calculations. Are there Simulink blocks for handling array elements?
I know that “Data Store Memory” exists and that they can be arrays but I do not see a way to write in new elements of an array. You can only write to the whole array.Thanks,Ron. Vijay Swaminathanreplied on: 47 of 123@Jim,Simulink goes from time =0 to time = Tfinal. If I understand your questions correctly, the easiest way to do this is Simulink would be to simple reverse the data you are integrating. When you import data into Simulink (from say the MATLAB workspace) you provide along with the Data (say 1 column), a time vector ( which should actually be the first column of you data matrix). Now you can simply flip your data (check out the function FLIPUD) and not flip your time vector.
Simuink will happily integrate forward in time, but you can always keep at the back of your mind that if the Simulink scope indicates a time of lets say 5.6 sec's, in your case that would correspond to a time of (Tfinal-5.6) secs.going backwards.I am sure there are more elegant ways to do this and I am eager to hear Seth's take on it, but here is a quick and dirty way to get it done. Vijay Swaminathanreplied on: 52 of 123@Jeremy,The error you would have got should point you in the right direction. The issue is simple this:Embedded MATLAB block generates C-code for the block before executing. The fundamental limitation being that dynamic sizing (allowed in MATLAB but not in C ) is not supported.Therefore, rand(5,4) works because at the time of compilation because the size is defined. Rand(a,b) will not work because a and b are only known at runtime. You might have to fall back on the old C trick of declaring a huge random matrix and 'selecting' the required dynamic size from that matrix ( there are plenty of Simulink blocks available for this selection operation).That being said, if you declaring a and b explicitly inside the EML fcn (i.e the values of a and b are not altered by inputs to the block), there should be no issues.i.e this should work just fine:function y = fcn% This block supports the Embedded MATLAB subset.% See the help menu for details.a=2;b=4;y = rand(a,b).
Pauloreplied on: 54 of 123Hi Seth, how are you?I have a doubt about simulink, I don't know if you can help me, but I'll say what I need to do.I want to use the HH:MM block of the Numeric Displays from Gauges library. But when I put this block with some input in it, an error occurs saying that the input have to be an string one. I have no idea on how to work with strings within the simulink.
I looked for it in the help, in the internet, in the demos, but I didn't find how to do it. How can I convert a number to a string in simulink?I'm modeling a Trip Computer of a vehicle and in somewhere in the model, I have to show the time of the trip based in some clock. I have to show this data in the HH:MM block or similar one.I would apreciate any help.Thank you in advance.Best regards,Paulo. Alexreplied on: 56 of 123I'm new to Simulink (about 2 weeks into it) and I've gotten an assignment that requires me to write a program that will read in a list of signal names and will modify an existing simulink model (using a bus selector going to a mux that outputs a logged signal) to the appropriate values using code. The reason why it needs to be coded is because there are about 7,000 signals coming in and we need to be able to check any given signal to make sure it's behaving as it should.I use findsystem, getparam, and setparam functions to make the necessary changes. The trouble I'm having is in connecting the bus selector and the mux. I've gone in and changed all the port destinations and sources in the 'PortConnectivity' block parameter to reflect where the actual lines should be going/coming from but haven't gotten any results with it.
Parallel To Serial Converter
No lines appear in the Simulink model to reflect the changes that are shown in the parameters of the blocks.Is there a way to create lines using code to connect these two blocks? Is there a better way to take in a huge number of inputs and output a variable number of desired signals to be logged?
Vijay Swaminathanreplied on: 60 of 123@usman,Real Time Workshop integrates seamlessly with Simulink to produce C code from Simulink models. You really dont have to jump through any hoops (like you describe above)to do this. As long as you have Real Time Workshop installed, you should simply be able to follow the steps listed below to generate code:1. Open you model in Simulink.2. Go to Simulation - Configuration Parameters3. Under Solver, ensure that you have a fixed stepsolver selected.4.
Serial To Parallel Converter Verilog Code
Under Real Time Workshop, click 'Build' and watch themagic happen. Ashish Guptareplied on: 69 of 123Hi Seth,I have landed up in a strange problem. 'Parfor' statement for parallel computing toolbox doesnot work inside simulink.
Parallel To Serial Converter Ic
I have tried to modify one of my m file s funtion block and it threw this error on my faceError evaluating registered method 'Outputs' of M-S-Function 'test1' in 'test/Level-2 M-file S-Function'. Error using parallelfunctionmakegeneralchannel/channelgeneral at 858Undefined function handle. The following is the MATLAB call stack (file names and line numbers) that produced this error:'C:Program FilesMATLAB1R2008atoolboxmatlablangparallelfunction.m' 752'C:Program FilesMATLAB1R2008atoolboxmatlablangparallelfunction.m' 564'C:Program FilesMATLAB1R2008aworktest1.m' 354. Prasadreplied on: 79 of 123HiI am trying to generate bode plot of system through simulink.I am sweeping a transfer function with a sinusoidal signal of amplitude 1 and frequency within some band. Say 1 rad/s to 1000 rad/s. I set the frequency as variable and run simulation for 10 cycles for each frequency.
Then, I compare the input and output peaks for last cycle. The peaks ratio gives me gain and the timing difference between peaks gives me phase lag of the system. Taking log10 of gain gives me magnitude plot.I compared this bode plot with the one generated by matlab command. They donot match beyond very small frequency range. Please comment on correctness of this method and also on, whether such technique can be used for simulink based systems.I dont know, whether such topic was already discussed earlier, if yes plz give me the link.ThanksPrasad. Dannyreplied on: 80 of 123I have a large Simulink model (about 100 inports). I am developing a Matlab script that will allow me and my coworkers to run this simulation.
The problem I'm trying to overcome is in importing variables from Matlab into the Simulink model.To keep it straight, I use the same variable names in Matlab as are used in the Simulink model. However, when the variables are transferred to Simulink, the variable names don't matter - it's the order in which they're listed.I can take the time to make sure every input is in the right order, but that won't solve my problem. There are about a half dozen people (around the world) who can add, remove, or renumber the inports. If they change something I'm unaware of, my script will send variable values to the wrong locations in the Simulink model.Do you have a work around that will match the variables between Matlab and Simulink by name instead of order? Chetanreplied on: 90 of 123Dear Sir,In the simulink demo of “Wind Farm (DFIG Phasor Model)”, the wind turbine is modelled using pitch control.
As per the wind turbine aerodynamics used, for a wind speed of 14 m/s, the unregulated rotor speed must be 1.4 pu. In that model the DFIG speed is maintained at 1.21 pu by using the pitch control. My observation is that if the pitch control is disabled, the rotor speed is not maintained at 1.4 pu, and it keep on changing as time passes.I am working with a model in which I need to get the maximum rotor speed corresponding to the wind speed.
I tried to maintain the rotor speed steady by changing rotor inertia (H), friction factor (F), stator and rotor resistances, but without any result.Can you help me to stabile the unregulated rotor speed of the DFIG (without pitch control) for each wind speed?Thanks,Chetanchetankv01@gmail.com. Bindureplied on: 94 of 123sir,I have a simulink model from which some datas are taken into a matlab file.so when this file is executed i will get some estimated parameters which are to be taken again into the same model.This type of online simulation is it possible sir? It is apeed control problem.Motor is simulated in simulink.The speed estimation is done with matlab program.Finally I want to control the speed in simulink.Idont know how to tackle this?How can i load the data from matlab to simulink?I expect a reply from you sir. Your advise was very much helpful for me before also.Thanks in advanceBindu. Guyreplied on: 99 of 123Hi Vipul,My first guess is that you did not set the initial condition of the second integrator block (the one generating x1) to a value of 2.You can compare the model you created with the model 'vdp.mdl' shipped with Simulink.
Type 'vdp' at the MATLAB command prompt to open it. Since the model is small, you can compare the dialog parameters of all blocks.As a side note, to compare larger models I recommend using the XML comparaison included with Simulink Report Generator.I hope this helps.Guy. Markreplied on: 112 of 123Hello,I am trying to call sim from a Matlab function.I can do it from a Matlab script just fine, but when I try it from a function, Simulink doesn't seem to know the values of the simulation variables that I define in the function where I call sim. When I step through to debug these variables are being defined in the work-space just prior to the call to sim.Is it possible to call sim from a Matlab function? Or, does this have to be done from a script?THanks,Mark.