OPC Server: Start Stop Pause getData(again use) DYMOLA MATLAB - matlab

I am using a Dymola OPC server
DYMOLA HAS these many tags which can be controlled using SimControl.Run, SimControl.Stop ,etc
here i wrote it in MATLAB
hostInfo = opcserverinfo('localhost');
da = opcda('localhost','Dymosim.OPCServer.1');
connect(da);
fprintf("CONNECTED\n");
grp=addgroup(da,'Demo');
itmIDs={'ModelVariables.Tco','ModelVariables.der(Tco)'};
itm=additem(grp,itmIDs);
area=additem(grp,{'ModelVariables.Area'});
set(grp,'UpdateRate',0.2,'RecordsToAcquire',50);
start(grp);
wait(grp);
[logIDs,Tco]=getdata(grp,'double'); // PREVIOUS ONE
Now I want to change/write value to area so what I did is this
write(area,23);
Now I want to Relog or getdata
NEWTco=read(itm,'device').Value; //using This I can read one instance
[NewlogIDs,NewTco]=getdata(grp,'double');// GIVES ERR

Writing this helped me to solve this issue
grp2=addgroup(da,'Demo2');
Run=additem(grp2,{'SimControl.Run'});
Status=additem(grp2,{'SimControl.Status'});
Stop=additem(grp2,{'SimControl.Stop'});
Pause=additem(grp2,{'SimControl.Pause'});
RunStatusBefore=read(Run,'device');
StatusBefore=read(Status,'device').Value;
StopStatusBefore=read(Stop,'device');
PauseStatusBefore=read(Pause,'device');
write(Initialize,1); //INITITALIZE
write(Run,1); // RUN
write(Stop,1); // STOP
write(Pause,1); // PAUSE

Related

How do I use system time as a trigger in codesys ladder?

Programming a raspberry pi with codesys, using mostly ladder, basically I need to write all data that is currently in a couple arrays to a csv file at midnight, so i'd like to be able to use a dt value as a trigger. I can't figure out how to use that value in ladder, however. I can display the local time on visualizer, but if i wanted something like "if localTime=#value" then coil 'Write' turns on, where is the actual variable for system time?
As far as I know, you need to read the clock from local system using function blocks, for example GetDateAndTime from CAA DTUtil Extern Library. Then you need to keep it up-to-date by using a function block, for example RTC from Standard libary
The following reads the system local time and then updates it with a RTC function block. Works at least on Windows, couldn't test with Raspberry. Please note that if the local time changes for some reason, this won't update it again. So you need to run the GetDateAndTime call every now and then, for example.
First, a program that updates and provides the local time:
PROGRAM PRG_UpdateSystemTime
VAR_OUTPUT
SystemDateTime : DT;
END_VAR
VAR
ReadLocalTime : DTU.GetDateAndTime; //Reads local time from system
RtcBlock : RTC; //Real-time clock - updates the previously received local time
END_VAR
//NOTE: Output is UTC time
//The block that reads local time. NOTE: Error handling is missing
ReadLocalTime(xExecute:= TRUE);
//Running real-time clock
RtcBlock(
EN := ReadLocalTime.xDone AND NOT ReadLocalTime.xError,
PDT := ReadLocalTime.dtDateAndTime,
CDT => SystemDateTime
);
And then one example for ladder. I think there are millions of ways. Note that the "DoSomething" will be TRUE for the whole second, so you should probably use rising edge detection.

serial monitoring method to test communication via com ports without a serial communication device

I have a Verilog code simulated and synthesized on ISE design toolkit. I've got an FPGA spartan 6 device which is to be used for the implementation. But there is a problem with the device (probably a power issue) which makes the device unavailable in any of the COM ports when I connected it to my PC. So I want to check whether my Matlab code which I made for serial communication through the device does the desired job. So I need a method to test serial communication via any of the COM ports without connecting a serial com device to the PC. Is there any such method that I can Tx Rx serial data from Matlab to COM ports? Any software or any other method would be highly appreciated :)
I found a way to test Matlab serial communication using virtual serial ports.
Download "Freeware Virtual COM Ports Emulator" from: http://freevirtualserialports.com/
I installed it in Windows 10, and it's working (as trial).
Add a pair of two serial ports:
Execute the following Matlab code sample to verify it's working:
s3 = serial('COM3','BaudRate',115200);
s4 = serial('COM4','BaudRate',115200);
fopen(s3);
fopen(s4);
fwrite(s3, uint8([1, 2, 3, 4, 5]));
%fprintf(s3, '12345');
pause(0.1);
RxBuf = fread(s4, 5)
fclose(s3);
delete(s3);
clear s3
fclose(s4);
delete(s4);
clear s4
The output is:
RxBuf =
1
2
3
4
5
Bypassing the problem "it only stays for a single test session".
There is a problem when creating a pair of virtual ports using the software, it only stays for a single test session.
I guess it's a problem with the COM port emulation software.
The following solution, is not a good practice (and not a true solution).
Declare the serial object as global, keeping the object persistent.
Create the serial object only if it's not created.
Don't delete and don't clear the serial object.
See the following code sample:
global s3 s4
if isempty(s3)
s3 = serial('COM3','BaudRate',115200);
end
if isempty(s4)
s4 = serial('COM4','BaudRate',115200);
end
fopen(s3);
fopen(s4);
fwrite(s3, uint8([1, 2, 3, 4, 5]));
pause(0.1);
RxBuf = fread(s4, 5)
fclose(s3);
%delete(s3);
%clear s3
fclose(s4);
%delete(s4);
%clear s4
You can also look for a better virtual COM port software.
As Rotem suggested, if you need to communicate via serial line between 2 program of your PC you need a virtual COM port emulator.
It seems you are running on Windows OS so I would recommend a completely free emulator (not a trial one). For Windows I use com0com Null-modem emulator (from SourceForge).
In the example below I will show how to communicate with "another" device so Matlab will not handle both side of the communication. The other device will be simulated by a simple terminal. For windows I use RealTerm: Serial/TCP Terminal (also from SourceForge).
Setup:
Execute the setup of both program with all default options. by default com0com will create a virtual pair COM3/COM4 but if these port already exist on your system the program may assign other numbers. Check the numbers before you run the example. (it will also create a CNCA0/CNCB0 pair but you can ignore this one for now).
For RealTerm, once installed (don't forget to activate the server registration at the end of the setup, it should be ticked by default though), it will look like below. Keep all default options, just set the port number and the baud rate if they need to be changed.
Test MATLAB -> Terminal
You are ready to send Ascii characters or binary values from MATLAB to your device. The animation below shows you an example of both option:
you can click on the picture to see it full size. It is running in loop so you may want to wait until it restart from the beginning.
Test Terminal -> MATLAB
Below animation shows you how to test the communication in the other way:
Don't forget to tick [CR] [LF] on RealTerm when you send Ascii characters and want to use the '%s' format specifier on MATLAB, as it needs these characters to detect the end of the string.
Note:
If you have another terminal program that you are more used too, it
will work the same.
If the RealTerm option does not suit you, or if you want to handle
both sides of communication from Matlab, then you can use the code
provided by Rotem in his first answer. Just install com0com but
ignore all the RealTerm part.

Matlab - Interactive Brokers - Getdata function

I am using the getdata function of the trading toolbox in Matlab (http://de.mathworks.com/help/trading/ibtws.getdata.html) to get real time price data of forex pairs (e.g. EURUSD) through the most up to date TraderWorkStation (TWS) with an Interactive Brokers (IB) demo account using the most recent API offered by IB (v9.71).
The TWS is running while executing my code (see below)
Here is the code I am using. It follows all the basic steps explained in the follwing tutorial by Mathworks (http://de.mathworks.com/videos/get-started-with-trading-toolbox-connect-to-interactive-brokers-1-of-3-91839.html).
% establish connection to TWS
ib = ibtws('',7497);
%% create currency handles
ibEURUSD = ib.Handle.createContract;
% set forex credentials
ibEURUSD.symbol = 'EUR';
ibEURUSD.secType = 'CASH';
ibEURUSD.exchange = 'IDEALPRO';
ibEURUSD.currency = 'USD';
cur = getdata(ib,ibEURUSD);
% close IB connection
close(ib);
In most of the cases (roughly 75%) this code deliveres the expected results and returns the requested financial data. However, in the remaining cases the variable "cur" does not contain the requested price data but the following error message: "HMDS data farm connection is OK:ushmds"
Which fist does not look like a problem. However this error message replaces the requested data so that during 25% of the runs no data will be received.
I apprechiate any hints to solve this.
It's bug in the MATLAB Trading Toolbox. There are a few messages that the IB API documentation describes as being safe to ignore, but the MATLAB errMsg event handler does not ignore them and instead terminates the ongoing getdata request while the price data is being received. The "HMDS data farm connection is OK:ushmds" is message number 2106 which is one of the ignorable messages.
Consider using the IB-Matlab connector, which does not have this problem.

Ros publisher not working with V-Rep after saving

I've started using V-Rep to simulate some robots (Pioneers and quadrotors, initially), but I've been having problems when I try to connect it with ROS. I tried to replicate the example from RosTopicPublisherAndSubscriber.ttt and it only works the first time, after I close it and load it again, it doesn't work anymore, my code is practically identical to the example, except that I use getPose and it's a Pioneer (the one that comes with V-Rep), here's my code:
if (simGetScriptExecutionCount()==0) then
-- Check if the required plugin is there (libv_repExtRos.so or libv_repExtRos.dylib):
local moduleName=0
local moduleVersion=0
local index=0
local pluginNotFound=true
while moduleName do
moduleName,moduleVersion=simGetModuleName(index)
if (moduleName=='Ros') then
pluginNotFound=false
end
index=index+1
end
if (pluginNotFound) then
simDisplayDialog('Error','ROS plugin was not found.&&nSimulation will not run properly',sim_dlgstyle_ok,false,nil,{0.8,0,0,0,0,0},{0.5,0,0,1,1,1})
else
-- Retrive the handle of the vision sensor we wish to stream:
lHandle=simGetObjectHandle('Pioneer_p3dx')
-- Now enable topic publishing and streaming of the vision sensor's data:
topicName=simExtROS_enablePublisher('p3dx',1,simros_strmcmd_get_object_pose,lHandle,0,'')
if (topicName == nil) then
simDisplayDialog('Error','Nil',sim_dlgstyle_ok,false,nil,{0.8,0,0,0,0,0},{0.5,0,0,1,1,1})
else
simDisplayDialog('Error','Not Nil',sim_dlgstyle_ok,false,nil,{0.8,0,0,0,0,0},{0.5,0,0,1,1,1})
end
-- Retrive the handle of the passive vision sensor. We will use the passive vision sensor
end
end
Any idea is welcome! Thanks in advance!
PS: Also, if anyone with 1500 reputation points could create the v-rep tag, that would be great!
Ok, the people at V-REP helped me solve it. So basically I should used the argument as -1 instead of 0.
So basically, a should have done this
topicName=simExtROS_enablePublisher('p3dx',1,simros_strmcmd_get_object_pose,lHandle,-1,'')
instead of
topicName=simExtROS_enablePublisher('p3dx',1,simros_strmcmd_get_object_pose,lHandle,0,'')

Continuously acquire data in MATLAB using callbacks and persistent variables

I have just recently started to use MATLAB to acquire data off of a data acquisition board and was in need of a function to acquire data continuously (i.e. until I ctrl^C out of the function). To do this I am using the data acquisition toolbox on a 32-bit windows OS.
Based on the documentation in matlab help and a few of the answers on this site, I found that after adding channels to my input handle I should:
set my 'SamplesPerTrigger' to Inf
set the 'TimerPeriod' to some value to trigger the 'TimerFcn'
set the 'TimerFcn' to some subfunction callback which appends data to a persistent variable
Is this a correct way to do this?
My code is as follows:
function acquire_arena_test(samprate,daq_device ,device_ID ,channels, saveroot)
setup.SampleRate = samprate;
setup.DAQdevice = {daq_device, device_ID};
setup.AIChannels = channels;
setup.SaveRoot = {saveroot};
ai = analoginput(setup.DAQdevice{1},setup.DAQdevice{2});
addchannel(ai,[setup.AIChannels]);
set(ai,'SamplesPerTrigger',Inf);
set(ai,'TimerPeriod',0.5);
set(ai,'TimerFcn',{#AcquireData,ai});
start(ai);
while(strcmpi(get(ai,'Running'),'On'))
pause(1)
end
stop(ai);
time = datestr(now,30);
save([saveroot time], 'data');
delete(ai);
clear ai;
function AcquireData(hObject, ~)
persistent totalData;
data = getdata(hObject);
if isempty(totalData)
totalData =data;
else
totalData = [totalData; data];
end
The initial analog input is definitely working properly. I have tried many permutations of giving the AcquireData callback to 'TimerFcn'. The error I receive is
`??? Error using ==> acquire_arena_test>AcquireData
Too many input arguments.
Warning: The TimerFcn callback is being disabled.
To enable the callback, set the TimerFcn property. `
Thanks in advance for any help.
I think the syntax you use for setting up your TimerFcn is wrong. You write
set(ai,'TimerFcn',{#AcquireData,ai});
but this means that your function AcquireData will be called with tree parameters: AcquireData(ai, event, ai) as explained here, which then of course triggers the error message since your AcquireData function only accepts two parameters. Just change your code to
set(ai,'TimerFcn',#AcquireData);
and it should work; the ai object is automatically passed as the first parameter (see the link to the MATLAB documentation above).
Sorry about answering my own question, but I figured it out. The trigger was not needed after all. Using a national instruments board (or a sound card, as it turns out) you can just change the LoggingMode to 'disk' and specify a file to save the .daq (data acquisition toolbox) file to save as with LogFileName. If you want to use the memory on your board, change the mode to disk&Memory. Helpful document:
http://www.mathworks.com/help/toolbox/daq/f12-16658.html
The script below acquires data during the pause, which is as long as you want it to be..
daqreset;
clear all;
ai = analoginput('nidaq','Dev1');
chans = addchannel(ai,0:6);
set(ai,'SamplesPerTrigger',Inf);
set(ai,'SampleRate',1000)
set(ai,'LogToDiskMode','Overwrite')
set(ai,'LogFileName','log.daq')
set(ai,'LoggingMode', 'disk')
start(ai)
pause()
stop(ai)
data = daqread('log.daq');
delete(ai);
Note that you still need to set 'SamplesPerTrigger' to Inf for this to work properly. Thank you to Jonas for his help as well.