My issue involves using the RS-232 Simulink RT blocks.
A model is uploaded to the target PC (xPC) and it transmits and receives data from a variable frequency drive (VFD) that controls a motor. The issue arises on the receiving end when I take data and try to send that data to a display block in my model as a string. Code would be helpful here:
disp = uint8(zeros(1,24));
display = uint8(zeros(1,length(disp)));
cmd = 0;
status = stat_lb;
%% Start-Up
% Initialization Period
if (status == 0 || status == 1)
cmd = 0;
msg = uint8('Start up');
display = [msg uint8(zeros( 1, length(disp)- length(msg) ))];
end
...
%Multiple status cases with unique displays.
...
disp = display
So, here the cmd portion functions as expected. As noted above, I want to display the display string on a display block in my Simulink model. As you can see, though, it is of type uint8, so I need to convert it to type string; however, when I pass it through either the ascii2str Simulink block or just place it in the function call (e.g. display = ascii2str(display)) I get the following error message:
Executing the 'CheckData' command produced the following error: Invalid parameter/value pair arguments
My thought is that this has something to do with the fact that I am using MEX and this function (ascii2str) is not supported. Anyways, I am wondering if anyone knows why I receive this error and if there is anything I can do to resolve it.
Oh, and one last thing: I can get the display to work if I just remove the ascii2str; however, the only problem with this is that the display is in uint8 form and not really helpful. So, if there is any other way that I can decode the uint8 to a string I am all ears.
Thanks!
I have found that there is no support for this feature in Simulink RT. One option is to use external functions, but I found it better for my application to simply output a number and have a table in the simulation that explained what each number meant.
Related
I'm trying to retrieve the serial number from a drive using the MC_BR_GetHardwareInfo function block. Since the documentation lacks any kind of example code on this topic I'm getting nowhere.
Which information should I provide to the function block in order to get the desired serial number?
Below sample will crash in the PLC, probably because the function block requires certain pointers to be addressed:
MC_HARDWARE_INFO_REF hwinfo;
MC_BR_GetHardwareInfo(&hwinfo);
You are probably getting a page fault, because you provide the MC_BR_GetHardwareInfo function block (FUB) a wrong type, which leads to random behavior.
A function block is basically a function which requires a reference to a specific type as parameter. This type contains the actual in- and outputs which are used, internal state variables, etc. We need this, because of the synchronous execution of the code. This means unlike a function, you need to call a FUB until it is done.
Let's take a look to the help of the FUB:
Guid: 056444ea-2a15-4af6-a5ae-0675894b17d3
So the FUB needs a reference to the Axis object of which you want to know the HW info and an Execute command. It will give you some status bits, an error code and the actual data you want to have within the structure HardwareInfo of the type MC_HARDWARE_INFO_REF.
First we need to instantiate the FUB by create a variable of its type. We do this in the local *.var file of the task:
VAR
fbGetHwInfo : MC_BR_GetHardwareInfo := (0);
END_VAR
Then we call set the parameters of the FUB and call it, which might look like this:
void _CYCLIC ProgramCyclic(void)
{
//should be set by the application or in watch/monitor; now it only
//executes once
fbGetHwInfo.Execute = 1;
//reference to your axis object; when using a wizard the first axis
//will be gAxis01 on default
fbGetHwInfo.Axis = (UDINT)&gAxis01;
//call the FUB
MC_BR_GetHardwareInfo(&fbGetHwInfo);
if(fbGetHwInfo.Error == 1)
{
//TODO: errorhandling
}
else if(fbGetHwInfo.Done == 1)
{
//TODO use output
//fbGetHwInfo.HardwareInfo
}
}
typically you would do this in some statemachine. Also you probably have to wait until the network to the drive is initialized. You could check this with the MC_BR_ReadDriveStatus FUB. Just for testing it should be enough to wait for some seconds after reboot and set the Execute flag in monitor mode.
I have been trying to write a working program that takes in data from a UDP socket and displays it in an edit control box as you receive the data (My exposure to c++ is also only about a week :P have only done embedded C code before). I have a working program that can send and output data on a button click but I want something that can do it in real time. The aim is scale this up into a larger GUI program that can send control data to hardware and get responses from them.
I have run into various problems including:
The program just not executing my OnReceivefunction (derived from
CAsyncSocket)
Getting the OnReceive function to run on a separate thread so that it can still run after a button has been clicked sending a control packet to the client then waiting for a response in a while loop
Not being able to output the data in the edit box (tried using both CEdit and CString)
ReplaceSel error saying that the type char is incompatible with LPCTSTR
My code is based on this codeproject.com tutorial, being almost exactly what I want but I get the error in 4.
EDIT: the error in 4. disappears when I change it to a TCHAR but then it outputs random chinese characters. The codeproject.com tutorial outputs the correct characters regardless of char or TCHAR declaration. When debugged my code has type wchar_t instead type char like the other code.
Chinese output
In the working program echoBuffer[0] the character sent and displayed was a 1
UINT ReceiveData(LPVOID pParam)
{
CTesterDlg *dlg = (CTesterDlg*)pParam;
AfxSocketInit(NULL);
CSocket echoServer;
// Create socket for sending/receiving datagrams
if (echoServer.Create(12345, SOCK_DGRAM, NULL) == 0)
{
AfxMessageBox(_T("Create() failed"));
}
for (;;)
{ // Run forever
// Client address
SOCKADDR_IN echoClntAddr;
// Set the size of the in-out parameter
int clntAddrLen = sizeof(echoClntAddr);
// Buffer for echo string
char echoBuffer[ECHOMAX];
// Block until receive message from a client
int recvMsgSize = echoServer.ReceiveFrom(echoBuffer, ECHOMAX, (SOCKADDR*)&echoClntAddr, &clntAddrLen, 0);
if (recvMsgSize < 0)
{
AfxMessageBox(_T("RecvFrom() failed"));
}
echoBuffer[recvMsgSize] = '\0';
dlg->m_edit.ReplaceSel(echoBuffer);
dlg->m_edit.ReplaceSel(_T("\r\n"));
}
}
After reading the link that #IInspectable provided about working with strings and checking the settings differences between the two programs it became clear that the issue lay with an incorrect conversion to UNICODE. My program does not require it so I disabled it.
This has cleared up the issue in 4. and provided solutions for 2 and 3.
I also think I know why another instance of my program would not run OnReceivein 1. because that file was not being defined by one that was already being run by the program, but that is now irrelevant.
I have a ".mat" file supposedly containing a [30720000x4 double] matrix (values from accelerometers). When I try to open this file with "Import data" in Matlab I get the following error:
Error using load
Can't read file F:\vibration_exp_2\GR_UB50n\bearing1\GR_UB50n_1_2.mat.
Error using load
Unknown text on line number 1 of ASCII file
F:\vibration_exp_2\GR_UB50n\bearing1\GR_UB50n_1_2.mat
"MATLAB".
Error in uiimport/runImportdata (line 456)
datastruct = load('-ascii', fileAbsolutePath);
Error in uiimport/gatherFilePreviewData (line 424)
[datastruct, textDelimiter, headerLines]= runImportdata(fileAbsolutePath,
type);
Error in uiimport (line 240)
[ctorPreviewText, ctorHeaderLines, ctorDelim] = ...
The filesize is 921MB which is the same as my other files that do open. I also tried opening the file using python, but no success. Any suggestions? I use MATLAB R2013b .
More info:
How the file was create:
%% acquisition of vibration data
% input:
% sample rate in Hz (max. 51200 Hz, should be used as bearing
% faults are high-frequent)
% time in seconds, stating the duration of the measurement
% (e.g. 600 seconds = 10 minutes)
% filename for the file to be saved
%
% examples:
% data = DAQ(51200, 600, 'NF1_1.mat');
% data = DAQ(51200, 600, 'NF1_2.mat');
function data = DAQ(samplerate,time,filename)
s = daq.createSession('ni'); % Creates the DAQ session
%%% Add the channels as accelerometer channels (meaning IEPE is turned on)
s.addAnalogInputChannel('cDAQ1Mod1','ai0','Accelerometer');
s.addAnalogInputChannel('cDAQ1Mod1','ai1','Accelerometer');
s.addAnalogInputChannel('cDAQ1Mod1','ai2','Accelerometer');
s.addAnalogInputChannel('cDAQ1Mod1','ai3','Accelerometer');
%s.addAnalogInputChannel('cDAQ1Mod2','ai0','Accelerometer');
s.Rate = samplerate;
s.NumberOfScans = samplerate*time;
%%% Defining the Sensitivities in V/g
s.Channels(1).Sensitivity = 0.09478; %31965, top outer
s.Channels(2).Sensitivity = 0.09531; %31966, back outer
s.Channels(3).Sensitivity = 0.09275; %31964, top inner
s.Channels(4).Sensitivity = 0.09363; %31963, back inner
data = s.startForeground(); %Acquiring the data
save(filename, 'data');
More info:
When I open the file using a simple text editor I can see a lot of characters that do not make sense but also the first line:
MATLAB 5.0 MAT-FILE, Platform: PCWIN64, Created on: Thu Apr 30
16:29:07 2015
More info:
The file itself: https://www.dropbox.com/s/r7mavil79j47xa2/GR_UB50n_1_2.mat?dl=0
It is 921MB.
EDIT:
How can I recover my data?
I've tried this, but got memory errors.
I've also tried this, but it did not work.
I fear I can't add many good news to what you know already, but it hasn't been mentioned yet.
The reason the .mat-file can't be load is due to the data beeing corrupted. What makes it 'unrecoverable' is the way it is stored internally. The exact format is specified in the MAT-File Format Documentation. So I decided to manually construct a simple reader to specifically read your .mat file.
It makes sense, that the splitmat.m can't recover anything, as it will basicly split the data into chunks, one stored variable per chunk, however in this case there is only 1 variable stored and thus only one chunk, which happens to be the corrupted one.
In this case, the data is stored as a miCOMPRESSED, which is a normal matlab array compressed using gzip. (Which, as a side note, doesn't seem like a good fit for 'random' vibration data.) This might explain previous comments about the smaller file size then the full data, as the filesize matches exatly with the internally stored value.
I extracted the compressed archive and tried to uncompress it in a variety of ways. Basicly it is a '.gz' without the header, that can be appended manually. Unfortunatly there seems to be a corrupted block near the start of the dataset. I am by no means an expert on gzip, but as far as I know the dictionary (or decryption key) is stored dynamicly which makes all data useless from the point the block is corrupted. If you are really eager, there seems to be a way to recover data even behind the point where data is corrupted, but that method is massively timeconsuming. Also the only way to validate data of those sections is manual inspection, which in your case might proof very difficult.
Below is the code, that I used to extract the .gz-file, so if you want to give it a try, this might get you started. If you manage to decrypt the data, you can read it as described in the MAT-File Format, 13f.
corrupted_file_id = fopen('corrupt.mat','r');
%% some header data
% can be skipped replacing this block with
% fread(id,132);
%header of .mat file
header_text = char(fread(corrupted_file_id,116,'char')');
subsystem_data_offset = fread(corrupted_file_id,8,'uint8');
version = fread(corrupted_file_id,1,'int16');
endian_indicator = char(fread(corrupted_file_id,2,'int8')');
data_type = fread(corrupted_file_id,4,'uint8');
%data_type is 15, so it is a compressed matlab array
%% save te content
data_size = fread(corrupted_file_id,1,'uint32');
gz_file_id = fopen('compressed_array.gz','w');
% first write a valid gzip head
fwrite(gz_file_id,hex2dec('1f8b080000000000'),'uint64',0,'b');
% then write the data sequentialy
step = 1:1e3:data_size;% 1MB steps
for idx = step
fwrite(gz_file_id,fread(corrupted_file_id,1e3,'uint8'));
end
step = step(end):data_size;% 1B steps
for idx = step
fwrite(gz_file_id,fread(corrupted_file_id,1,'uint8'));
end
fclose(gz_file_id);
fclose(corrupted_file_id);
To answer literally to the question, my suggestion would be to make sure first that the file is okay. This tool on File Exchange apparently knows how to diagnose corrupted .MAT files starting with version V5 (R8):
http://www.mathworks.com/matlabcentral/fileexchange/6893-matcat-mat-file-corruption-analysis-tool
The file's size (indices going out of range) seems to be a problem. Octave, which should read .mat files, gives the error
memory exhausted or requested size too large for range of Octave's index type
To find out what is wrong you may need to write a test program outside MatLab, where you have more control over memory management. Examples are here, including instructions on how to build them on your own platform. These stand-alone programs may not have the same memory issues. The program matdgns.c is specifically made to check .mat files for errors.
The MATLAB imread function provides the ability to read an image from a URL. This generally works OK, but occasionally I encounter an image that takes a very long time to respond.
For instance, at the time of posting the following URL appears to just be stuck in a 'connecting...' state for over 5 minutes before finally succeeding.
http://www.hollywoodheadache.com/wp-content/uploads/2007/12/tom-and-julia.jpg
Is there any way I can set a timeout within MATLAB?
Thanks
I don't know how to interrupt imread with a timer object. Besides, I suspect about its possibility. But I may recommend you to check whether you can access to the file first, and then, you get the file. I have written the following function to check the file and internet status:
function flag = does_url_exist(urlName)
url =java.net.URL(urlName);
try
link = openStream(url);
parse = java.io.InputStreamReader(link);
snip = java.io.BufferedReader(parse);
if ~isempty(snip)
flag = 1;
else
flag = 0;
end
catch exception
flag = 0;
end
end
Then it is as follows:
fname = 'http://www.hollywoodheadache.com/wp-content/uploads/2007/12/tom-and-julia.jpg';
if(does_url_exist(fname))
img = imread(fname);
end
Note that for internet connection checking, I took the initial code from this post. Also note that if you are sure that the file exists, it is not efficient to check it again since it increases the running time.
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.