Read and write analog fast varying signal simultaneously using Ni 6008 + vb6 code

i want to write analog fast varying signal to AO same time I want read analog signal simultaneously each after 10 millisecond I am using vb6 platform.
Kindly help...

http://forums.ni.com/t5/Measurement-Studio-for-VB6/simultaneous-read-amp-amp-write-fast-varying-anal...

Similar Messages

How to read and write Xml file at client side using JavaScript !

Hello,
i am new to javascript.
I have requirement to read and update XML file at client side.
Will you please guide what could be the best way to read and update XMl file using javascript.
Thanks,
Zuned

This is a Java forum,not a Javascript forum. Maybe you should ask here [http://www.webdeveloper.com/forum/forumdisplay.php?forumid=3&s|http://www.webdeveloper.com/forum/forumdisplay.php?forumid=3&s].

How to read and write to the same external HDD using Mac and PC

Hello,
I am using a mid 2014 MacBook Pro.
I read somewhere that to write to an external HDD from a Mac, you need to format it in a particular way.
But this would stop it from being used on my PC. Is there any way I can write to the same HDD from both OSes ?
Thanks !

Yes. Format the HDD to FAT or ExFAT. It seems best to do that on a PC.
Ciao.

How to read and write a data from extrenal file

Hi..
How to read and write a data from extrenal file using Pl/sql?
Is it possible from Dyanamic Sql or any other way?
Reagards
Raju

utl_file
Re: How to Create text(dat) file.
Message was edited by:
jeneesh

Pbs to read and write messages on the same port

Hello,
I am novice so I do some tests to send messages with the example : CAN trasmit periodic, and to receive messages with the Channel Monitor, so I want to use this two VIs in my program but there is an error because I can't use the two examples at the same time...
How can I proceed to use this two example in my program? There is an other solution to read and write in the same time (I use a database .dbc)?
Bye

I'm sorry for my mistake but CAN transmit periodic exist in two version, one for FPGA and other for PC card. I didn't see the second one.
You can monitor your CAN bus with NI-CAN BusMonitor: How Can I Monitor the NI-CAN Bus?
Regards,
Aurélien J.
National Instruments France
#adMrkt{text-align: center;font-size:11px; font-weight: bold;} #adMrkt a {text-decoration: none;} #adMrkt a:hover{font-size: 9px;} #adMrkt a span{display: none;} #adMrkt a:hover span{display: block;}
>> Du 30 juin au 25 août, embarquez pour 2 mois de vidéo-t'chat ! Prenez place pour un voyage au coe...

PCIe-6536 Simultaneous Read and Write

I have an application where I need to simultaneously read 24 bits (Ports 0-2) and write 8 bits (Port 3), using an external clock. The way it is done now is I create a read task and I create a write task. I send my external clock to PFI4 and PFI5, because two clock inputs are required (one for read, one for write). And I send a trigger signal to PFI3 to start and synchronize the tasks.
However it is not working correctly. My clock is ~15MHz and the reads and writes are off by a random number of a few clock cycles. For example when I start writing out Port 3, the reading into Ports 0-2 will start 2 or 3 or 4 clock cycles later.
Is there a way that I can read and write simultaneously that will work correctly??

I am still trying to figure out this problem. I want to simultaneously write bytes out of Port_3 and acquire 24 bit words into Ports 0-2. The only way I know to synchronize the tasks is to have them both start on a rising edge trigger signal on PFI3.
If my clock is a few hundred kilohertz, the tasks are synchonized. When the clock is over 1 MHz then I start seeing the read of 24-bit words lagging the output write by 1 clock cycle sometimes. The higher the clock rate, the more delay I see. With a 20MHz clock I see a lag of 8 or 9 or 10 clock cycles. I spent a lot of money on this card but it apparently doesn't work as advertised. It is supposed to work up to 25MHz but I have problems at 1MHz.
The way I am testing it is to loop Port_3 directly into Port_2 with a short ribbon cable (using the CB-2162 test board made for the I/O card). I can send a pattern out and read it in and see how many of the first bytes were not read in. For some reason the Acquire task is lagging the Generate task...

Fast way to read and write console

hi guys
what's the fastest way to read and write from console?
For writing I'm using (I think thats the fastest way)
System.out.println(foo)and I have to read the following - all numbers are ints (that means m + n + 1 lines):
1 * "<n> <m>"
n * "<a> <b> <c>"
m * "<a> <b>"Actual I'm reading (the second line for example) with
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String[] items = br.readLine().split("[^\\-\\.0-9]+");
Target mainTarget = new Target(Integer.parseInt(items[0]), Integer.parseInt(items[1]), Integer.parseInt(items[2]));
for (int i = 1; i < m; i++) {
items = br.readLine().split("[^\\-\\.0-9]+");
mainTarget.addTarget(Integer.parseInt(items[0]), Integer.parseInt(items[1]), Integer.parseInt(items[2]));
} But that isn't really fast...
have you any idea?
grz faetzminator

faetzminator wrote:
right, I have 1 + 1 + 1 =3 up to 10^6-1 + 10^6-1 + 1 =2*10^6-1 input lines with max 4999997 integers (and I have to store 2999999 of them)
ok, if that is the fastest way... (maybe the reading of the input file is so slow; I run eg "java Foo < input > output")All those br.readLine calls where you never check if the return is null are dangerous.
I really don't understand what you are doing. You mentioned System.in at first and now reading from files.
I also am pretty sure that you are in fact running out of memory.

How to increase disk read and write speed after installing new SSD (2009 Macbook Pro)? Why not as fast as advertised?

Hi everyone,
I just installed a Crucial MX10512 GB SSD into my 2009 Macbook Pro. It's definitely much faster, but the read and write disk speed is around 200 Mb/s for both versus the 300-500 Mb/s that the SSD advertised. Any ideas as to why? And is there anything I can do to make it faster? Before I installed it, it was between 80-90 Mb/s.
Specs:
- currently have about 460 of 511 GB of storage available
- am using 2GB of memory
- running on 10.10.2 Yosemite
Thanks!

nataliemint wrote:
Drew, forgive me for being so computer-incompetent but how would I boot from another OS? And shouldn't I be checking the read speeds on my current OS (Yosemite) anyways because I want to know how the SSD is performing on the OS I use? And finally, what kind of resources would it be using that would be slowing down my SSD?
Sorry for all the questions - I'm not a Macbook wiz by any means!
You could make a clone of your internal OS onto an external disk. Hopefully you already have a backup of some form
A clone is a full copy, so you can boot from it. It makes a good backup as well as being useful to test things like this.
Carbon Copy Cloner will make one or you can use Disk Utility to 'restore' your OS from the internal disk to an external one.
Ideally the external disk is a fast disk with a fast 'interface' like Thunderbolt, Firewire 800 or USB3. USB2 can work, but it is slow & may effect the test.
You connect the clone, hold alt at startup & select the external disk in the 'boot manager'. When the Mac is finished booting run the speed tester.
Maybe this one…
https://itunes.apple.com/gb/app/blackmagic-disk-speed-test/id425264550
Test the internal & compare to the previous tests
A running OS will do the following on it's boot disk…
Write/ read cache files from running apps
Write/ read memory to disk if memory is running low
Index new files if content is changing or being updated
Copy files for backing up (Time Machine or any other scheduled tasks)
Networking can also trigger read/ write on the disk too.
You may not have much activity that effects a disk speed test, but you can't really be sure unless that disk is not being used for other tasks.
Disk testing is an art & science in itself, see this if you want to get an idea …
http://macperformanceguide.com/topics/topic-Storage.html
Simply knowing that it's about twice the speed would be enough to cheer me up

Fast, small-byte reads and writes.

I am trying to communicate with a third-party counter using a 1 byte "start" command followed by reading a 4 byte number. I would like to perform this read/write pair as fast as possible as I will be using count-times on the order of microseconds repeated millions of times. Our first attempt used USB but the latency in the bus was way too slow at 1ms. We spent more time waiting than counting. We are currently considering GPIB since the latency should be only 30 microseconds but we're concerned that the overhead from labview will prevent us from reading and writing that fast. Another idea we had was to use digital I/O channels to create our own parallel port to by-pass the USB bus. Can anyone comment on a good solution for low-latency small-byte reads and writes from labview? What type of hardware is recommended and can labview support programmatic reads-writes on the order of microseconds? Thanks!

Theoretically GPIB is capable of very good latencies, as you say on the order of usec. But in the real world using real PCs running real operating systems and connected to real instruments, the latencies seem to cluster around 2-5msec, in my experience. The issue isn't LabVIEW so much as all the stuff through which instrumentation interactions must filter, including background processes, screen updates and all the rest of the activities which consume the processor's bandwidth. Some instruments allow you to buffer and interpret the next command while the current one is underway, then trigger it, which saves latency. Also keep in mind that your GPIB network will only be as responsive as the least-well-behaved instrument on the bus.

Instrument i/o assistant always generates async methods for read and write!

I am trying to generate VI by instrument i/o assistant, but it generated 'Visa write' and 'Visa read' always in asynchronous mode. Even if I unchecked asynch boxes in MAX->Visa Test Panel.
I need only synchronous mode! And it is very uncovenient after open front panel change Synchronous I/O Mode from Asynchronous to Synchronous!

postoroniy_v wrote:
Asynchronous mode does not work for my hardware.
and before Instrument i/o assistant generate diagram I have possibility to check requests and responses to/from my hardware. in this case everything is fine.
after generate does not work.
Is it possible you don't have a sufficient amount of wait time between a VISA Write and VISA read to give the instrument time to receive the communication and turn around a response? Take a look at Basic Serial Read and Write example VI. If you are using the I/O assistant and checking things manually, it will work because there is no way you can generate a Read too fast. It still would take a fraction of second to generate the write and do whatever clicking to generate the read.

Can you improve the speed of my CSV Reader and Writer?

hi all, i'm trying to develop a CSV Writer and Reader. i have done a good work to implement the special character and quoting it, it's also support multi line value but it's incredibly slow.
can someone help to make it faster?
here it's how to use the writer
char *stringhe_sorgenti[10] = {0};
out = OpenFile(nfile, VAL_WRITE_ONLY, VAL_TRUNCATE, VAL_ASCII);
for(i = 0; i < sizeof(stringhe_sorgenti)/sizeof(char*); i++){
stringhe_sorgenti[i] = (char*)calloc(200, sizeof(char));
sprintf(stringhe_sorgenti[0], "example1");
sprintf(stringhe_sorgenti[1], "example2");
scrivi_riga_csv(out, stringhe_sorgenti, sizeof(stringhe_sorgenti)/sizeof(char*), formato);
for(i = 0; i < sizeof(stringhe_sorgenti)/sizeof(char*); i++){
free(stringhe_sorgenti[i]);
CloseFile(out);
here is the writer
void scrivi_riga_csv(int file_handle, char *stringa_sorgente[], int numero_stringhe, int formato)
char delimitatore[2][2] = {{',', '\0'}, {';', '\0'}};
char stringa_destinazione[1024] = {0};
int index_destinazione = {0};
int index_start = {0};
int index_fine = {0};
int errore = {0};
int i = {0};
//int k = {0};
size_t lunghezza_stringa = {0};
for(i = 0; i < numero_stringhe; i++){
if(i != 0){
stringa_destinazione[index_destinazione++] = delimitatore[formato][0];
index_start = 0;
lunghezza_stringa = strlen(stringa_sorgente[i]);
// se la stringa sorgente
if( (FindPattern(stringa_sorgente[i], 0, lunghezza_stringa, delimitatore[formato], 0, 0) != -1) // contiene delimitatore
|| (FindPattern(stringa_sorgente[i], 0, lunghezza_stringa, "\"", 0, 0) != -1) // contiene parentesi
|| (FindPattern(stringa_sorgente[i], 0, lunghezza_stringa, "\n", 0, 0) != -1) // contiene a capo
// apro parentesi all'inizio
stringa_destinazione[index_destinazione++] = '"';
// metodo find pattern, piu' complesso ma piu' performante
do{ index_fine = FindPattern(stringa_sorgente[i], index_start, lunghezza_stringa - index_start, "\"", 0, 0);
if(index_fine != -1){
index_fine++;
// copio dall'inizio fino alle virgolette
CopyString (stringa_destinazione, index_destinazione, stringa_sorgente[i], index_start, index_fine - index_start);
index_destinazione += index_fine - index_start;
// ne aggiungo una dopo
stringa_destinazione[index_destinazione++] = '"';
// aggiorno la posizione di start e riparto con il while
index_start = index_fine;
}while(index_fine != -1);
CopyString (stringa_destinazione, index_destinazione, stringa_sorgente[i], index_start, lunghezza_stringa - index_start);
index_destinazione += strlen(stringa_sorgente[i]) - index_start;
// alla fine della riga chiudo la parentesi
stringa_destinazione[index_destinazione++] = '"';
else{
// altrimenti la copio semplicemente e shifto l'indice della stringa di destinazione
CopyString (stringa_destinazione, index_destinazione, stringa_sorgente[i], 0, lunghezza_stringa);
index_destinazione += strlen(stringa_sorgente[i]);
memset(stringa_sorgente[i], 0, strlen(stringa_sorgente[i]));
errore = WriteLine (file_handle, stringa_destinazione, strlen(stringa_destinazione));
if(errore == -1){
errore = GetFmtIOError();
MessagePopup("WriteLine -> WriteLine", GetFmtIOErrorString(errore));
return;
here how to read the file
char *stringhe_sorgenti[10] = {0};
for(i = 0; i < sizeof(stringhe_sorgenti)/sizeof(char*); i++){
stringhe_sorgenti[i] = (char*)calloc(200, sizeof(char));
out = OpenFile(nomearchivio, VAL_READ_ONLY, VAL_OPEN_AS_IS, VAL_BINARY);
leggi_riga_csv(out, stringhe_sorgenti, sizeof(stringhe_sorgenti)/sizeof(char*), formato);
strcpy(intestazione.data, stringhe_sorgenti[1]);
for(i = 0; i < sizeof(stringhe_sorgenti)/sizeof(char*); i++){
free(stringhe_sorgenti[i]);
CloseFile(out);
and here the reader
void leggi_riga_csv(int file_handle, char *stringa_destinazione[], int numero_stringhe, int formato)
char delimitatore[2][2] = {{',', '\0'},
{';', '\0'}};
char stringa_sorgente[1024] = {0};
int stringa_in_corso = {0};
int index_inizio_valore = {0};
int index_doublequote = {0};
int offset_stringa_destinazione = {0};
size_t lunghezza_stringa = {0};
int inquote = {0};
int errore = {0};
int i = {0};
for(i = 0; i < numero_stringhe; i++){
lunghezza_stringa = strlen(stringa_destinazione[i]);
memset(stringa_destinazione[i], 0, lunghezza_stringa);
do{ memset(&stringa_sorgente, 0, sizeof(stringa_sorgente));
errore = ReadLine(file_handle, stringa_sorgente, sizeof(stringa_sorgente) - 1);
// If ReadLine reads no bytes because it has already reached the end of the file, it returns –2.
// If an I/O error occurs, possibly because of a bad file handle, ReadLine returns –1.
// You can use GetFmtIOError to get more information about the type of error that occurred.
// A value of 0 indicates that ReadLine read an empty line.
if(errore == -1){
errore = GetFmtIOError();
MessagePopup("leggi_riga_csv -> ReadLine", GetFmtIOErrorString(errore));
return;
else if(errore == -2){
errore = GetFmtIOError();
MessagePopup("leggi_riga_csv -> ReadLine", "already reached the end of the file");
return;
else{
lunghezza_stringa = errore;
index_inizio_valore = 0;
// metodo find pattern, piu' complesso ma piu' performante
for(i = 0; i <= lunghezza_stringa; i++){
// se come primo carattere ho una " allora e' una stringa speciale
if(inquote == 0){
if(stringa_sorgente[i] == '\"'){
inquote = 1;
index_inizio_valore = ++i;
else{
// altrimenti cerco il delimitatore senza il ciclo for
i = FindPattern(stringa_sorgente, i, lunghezza_stringa - index_inizio_valore, delimitatore[formato], 0, 0);
if(i == -1){
// se non lo trovo ho finito la riga
i = lunghezza_stringa;
if(stringa_sorgente[i - 1] == '\r'){
i--;
if(stringa_in_corso < numero_stringhe){
CopyString (stringa_destinazione[stringa_in_corso], 0, stringa_sorgente, index_inizio_valore, i - index_inizio_valore);
offset_stringa_destinazione = 0;
stringa_in_corso++;
if(stringa_sorgente[i] == '\r'){
i++;
index_inizio_valore = i + 1;
if(inquote == 1){
// se sono nelle parentesi cerco le virgolette
i = 1 + FindPattern(stringa_sorgente, i, lunghezza_stringa - index_inizio_valore, "\"", 0, 0);
if(i == 0){
if(stringa_sorgente[lunghezza_stringa - 1] == '\r'){
lunghezza_stringa--;
// se non le trovo ho finito la riga, esco dal ciclo for
break;
// se incontro una doppia parentesi salto avanti
else if(stringa_sorgente[i] == '\"'){
continue;
// !!!! fondamentale non cambiare l'ordine di questi else if !!!!!
// se incontro una parentesi seguita dal delimitatore
// o se incontro una parentesi seguita dal terminatore
// \r = CR = 0x0D = 13
// \n = LF = 0x0A = 10
// a capo = CR + LF
else if( (stringa_sorgente[i] == delimitatore[formato][0])
|| (stringa_sorgente[i] == '\r')
|| (stringa_sorgente[i] == '\0')
// salvo il valore
inquote = 0;
if(stringa_in_corso < numero_stringhe){
CopyString (stringa_destinazione[stringa_in_corso], offset_stringa_destinazione, stringa_sorgente, index_inizio_valore, i - 1 - index_inizio_valore);
offset_stringa_destinazione = 0;
stringa_in_corso++;
if(stringa_sorgente[i] == '\r'){
i++;
index_inizio_valore = i;
// se sono andato a capo scrivo fino a dove sono e poi procedo con la nuova riga
if(inquote){
if(stringa_in_corso < numero_stringhe){
CopyString (stringa_destinazione[stringa_in_corso], offset_stringa_destinazione, stringa_sorgente, index_inizio_valore, lunghezza_stringa - index_inizio_valore);
strcat(stringa_destinazione[stringa_in_corso], "\n");
offset_stringa_destinazione += lunghezza_stringa - index_inizio_valore;
offset_stringa_destinazione++;
}while(inquote == 1);
// elimino le doppie parentesi
for(i = 0; i < numero_stringhe; i++){
index_doublequote = 0;
do{ lunghezza_stringa = strlen(stringa_destinazione[i]);
index_doublequote = FindPattern(stringa_destinazione[i], index_doublequote, lunghezza_stringa - index_doublequote, "\"\"", 0, 0); // contiene doppia parentesi
if(index_doublequote != -1){
index_doublequote++;
memmove (stringa_destinazione[i] + index_doublequote, stringa_destinazione[i] + index_doublequote + 1, lunghezza_stringa - index_doublequote);
}while(index_doublequote != -1);
return;

the format is CSV, i try to explain better what i'm doing.
our client asked to save acquisition data with header description in an excel readable format, i've decided to use .CSV and not .TDM because it's a simple txt file and we never used .TMD but i will propose to use it.
after some research on the internet i've found nothing to handle .CSV in CVI except from this csv_parse but i've found it difficult to be maintained so i've write it by my own hand.
i've written two example of how to use my function to read or write and i've copyed my function used to read and write.
in the write function i check with FindPattern if the string to be write contain some special character, if i find this i have to quote the string to respect the standard RFC4180 and if i find a quote i have to double it. aftere i've done this check i write the line in the file.
in the read function, that is more complicated, i:
check if the first character is a quote.
if it's not i copy the string until the delimitier or until the end of the line.
if it is i have a string with special character inside so:
i find the first quote in the string. when i've found i check if it's follwed by another quote. this means that in the starting message i was writing a single quote.
if it's not followed by another quote but it's followed by a delimiter or a carriage return i've finished the special line.
if i don't find it it means that the special quote have a carriage return inside and i have to check the next line. before checking the next line i save this in my string.
after this loop i check in every string if i have a double quote and i delete one.
the main problem is in the speed of this, i'm acquiring data at 1000 S/s with 8 active channel for 60 second so i have 480000 data to be stored, divided in 60.000 row and 8 column. to read a file like that my pc stay "locked" for 15 second or more.
i've tried to use the arraytofile function and it's extremly fast and i can also put header because the function can start from the last position in the file but the filetoarray function start from the beginning and i cannot read the header correctly. also if i'm using the european CSV with semicolon as delimiter with arraytofile i cannot select the semicolon but only the coma

Slow read and write operations on DAQmx

I am trying to build up a feedback control system using PCI-6052E and PCI-6722 cards, so that the computation of the control algorithm is performed on computer's CPU. I am trying to reach sampling period of 1kHz. It turns out that the bottleneck of my system are the read and write operations from and to cards that consume lot of processor time.
An example code (C#) that shows how the reads and writes are implemented is as attachment. On my tests the example code produces a read-time of 1000 samples on 6 channels 7.58s and a write-time of 4.69s. Is there any way to improve the performance?
The program is running on Windows XP on 1000Mhz processor.
Attachments:
DAQmxPerformanceTest.cs ‏3 KB

Petteri,
I don't have the hardware to reproduce this, but I have a few ideas. For analog output, are you creating a task, starting it, and calling write repeatedly, or are you simply calling write? While an AO Task will auto start on write, it will also go through the process of stopping when the write is complete. Which means next time you call write, the task will need to start again. It will be much more effecient if you explicitly call start on the task once, perform as many writes as required, and stop/clear the task when you are done. This same principle applies to you analog input reads as well.
I hope this helps,
Dan

Urgent: Please help. how to solve the time delay during buffer read and write using vc++

I need to continuously acquire data from daqmx card, write into a file and at the same time corelate (in terms of time) the data with signals from other instruments. The current problem is that there is time delay during read and write data into buffer,thus causing misalignment of the data from multiple instruments. Is there a way to solve the delay? or Is there a way to mark the time of the data acquisition in the buffer? If I know the starting time (e.g. 0) of data acquisition and sampling rate (e.g. 1kHz), can I simply add 1ms to each data sample in the buffer? The current code is shown below.
void DataCollectionWin::ConnectDAQ()
DAQmxErrChk(DAQmxCreateTask ("", &taskHandle));
    DAQmxErrChk(DAQmxCreateAIVoltageChan(taskHandle,"Dev1/ai0,Dev1/ai1,Dev1/ai2,Dev1/ai3,Dev1/ai4,Dev1/ai5,Dev1/ai16,Dev1/ai17,Dev1/ai18,Dev1/ai19,Dev1/ai20,Dev1/ai21,Dev1/ai6,Dev1/ai7,Dev1/ai22","",DAQmx_Val_Cfg_Default,-10.0,10.0,DAQmx_Val_Volts,NULL));
  DAQmxErrChk(DAQmxCfgSampClkTiming(taskHandle,"",1000.0,DAQmx_Val_Rising,DAQmx_Val_ContSamps,60000));
  DAQmxErrChk (DAQmxRegisterEveryNSamplesEvent(taskHandle,DAQmx_Val_Acquired_Into_Buffer,50,0,EveryNCallback,NULL));// Every 50 samples the EveryNSamplesEvent will be trigured, to reduce time delay.
  DAQmxErrChk (DAQmxRegisterDoneEvent(taskHandle,0,DoneCallback,NULL));
  DAQmxErrChk (DAQmxStartTask(taskHandle));
int32 CVICALLBACK EveryNCallback(TaskHandle taskHandle, int32 everyNsamplesEventType, uInt32 nSamples, void *callbackData)
DAQmxErrChk (DAQmxReadAnalogF64(taskHandle,50,10.0,DAQmx_Val_GroupByScanNumber,data,50*15,&read,NULL));
   //memcpy(l_data,data,6000);
SetEvent(hEvent);
l_usstatus_e[0]=g_usstatus[0];// signals from other instruments that need to be corelated with the data from daq cards.
l_optstatus_e[0]=g_optstatus[0];
if( read>0 ) // write data into file
   //indicator=1;
for (i=0;i<read;i++)
{  //fprintf(datafile,"%d\t",i);
  fprintf(datafile,"%c\t",l_usstatus_s[0]);
  fprintf(datafile,"%c\t",l_usstatus_e[0]);
        fprintf(datafile,"%c\t",l_optstatus_s[0]);
  fprintf(datafile,"%c\t",l_optstatus_e[0]);
          fprintf(datafile,"%.2f\t",data[15*i]);
//   sprintf( pszTemp, "%f", data[6*i]);
// pListCtrl->SetItemText(0, 2, pszTemp);
    //pWnd->m_trackinglist.SetItemText(0, 2, pszTemp);
     fprintf(datafile,"%.2f\t",data[15*i+1]);
     fprintf(datafile,"%.2f\t",data[15*i+2]);

Hello kgy,
It is a bit of a judgment call. You should just choose the board that you think has the most to do with your issue. For example, this issue was much more focused on setting up your data acquisition task than the Measurement Studio environment/tools, so the MultifunctionDAQ board would have been the best place for it. As for moving your post to another board, I do not believe that is possible.
Regards,
Dan King

Process using Webservice in Reader and Writer becomes slow while connecting processors

Hi,
I have a process that reads from a web service and writes to a web service. When I try to modify the code(after stopping the running process) by adding new processors or change the current connections, the connecting arrows take forever to connect and sometimes the director hangs for a long time. There is no issue in other processes where I read and write from staged data.
How to overcome this isue?
Appreciate the help!
Regards,
Ravi

Hi Nick,
Thanks for the advice. In the scenario where upgrade is not an option, is there any workaround to this issue?
What I've found is if I strip the next processor of all its connections, then it gets connected to the previous processor pretty quick.
EDQ hangs if the processor has other input/output connections and I try to connect it to another processor)
P1>---<P2> <P3 ---------- P2 to P3 connects fast as P3 is standalone
P1>---<P2> <P3>---<P4> ---------- In this case, when I try to connect P2 to P3, it hangs forever.
I've a complex process and just for adding a few processors in between, I will not be able to connect the rest of the processors all over.
Regards,
Ravi

Help ,ImageIO exception to read and write

Hi,
I'm dynamically creating image files through screens utility of java(prog name:- Test_ScreenShot.java) and saving
them in memory sequentially(pic0.jpg,pic1.jpg....etc).Simultaneously I'm accessing the saved files from another
independent application(Prog name:- Test_Main.java) through piping(executing the application like this "Java
Test_Screens|Java Test_Main").The application is in infinite loop.I'm using Version JDK 1.5
I use java Image to read and write image:-
My application was running well for days.But now I'm getting sudden exceptions.
I got an exception while trying to save an dynamically generated image file in the local memory using the Image
class.In brief I'm getting exactly 3 types of exceptions:-
1)java.io.FileNotFoundException: pic5.jpg (Access is denied)
2)"Exception in thread "main" java.lang.NullPointerException
3)Exception in thread "main" com.sun.image.codec.jpeg.ImageFormatException: Not a JPEG file: starts with 0xff 0xd9
Here is the code snippent I wrote:
/* Robot robot = new Robot();
BufferedImage image = robot.createScreenCapture(screenRect);
// save captured image to jpg file
ImageIO.write(image, "jpg", new File(outFileName));*/
And here is the exception I am finding (I never found this before, I executed the code many times )
=====================================================================================================================
1)Exception Type 1:-
java.io.FileNotFoundException: pic5.jpg (Access is denied)
at java.io.RandomAccessFile.open(Native Method)
at java.io.RandomAccessFile.<init>(RandomAccessFile.java:212)
at javax.imageio.stream.FileImageOutputStream.<init>(FileImageOutputStream.java:44)
at com.sun.imageio.spi.FileImageOutputStreamSpi.createOutputStreamInstance(FileImageOutputStreamSpi.java:37)
at javax.imageio.ImageIO.createImageOutputStream(ImageIO.java:391)
at javax.imageio.ImageIO.write(ImageIO.java:1483)
at Test_ScreenShot.main(Test_ScreenShot.java:112)
at Test_Main.main(Test_Main.java:466)
at Test_ScreenShot.main(Test_ScreenShot.java:129)
2)Exception Type 2:-
"Exception in thread "main" java.lang.NullPointerException
at Picture.width(Picture.java:84)
at Test_Edge_Detector.not_main(Test_Edge_Detector.java:38)
at Test_Main.main(Test_Main.java:88)"
============================================================================================
Now I tried the following as alternative of ImageIO(from jdk 1.2)
to read image:-
FileInputStream fis = new FileInputStream(file);
JPEGImageDecoder jpeg = JPEGCodec.createJPEGDecoder(fis);
jpeg.decodeAsBufferedImage();
fis.close();
But after running a long time suddenly its giving following exceptions:-
==============================================================================================
Exception Type 3:- )
Exception in thread "main" com.sun.image.codec.jpeg.ImageFormatException: Not a JPEG file: starts with 0xff 0xd9
at sun.awt.image.codec.JPEGImageDecoderImpl.readJPEGStream(Native Method)
at sun.awt.image.codec.JPEGImageDecoderImpl.decodeAsBufferedImage(Unknown Source)
Exception Type 4:- )
javax.imageio.IIOException: Not a JPEG file: starts with 0xff 0xd9
at com.sun.imageio.plugins.jpeg.JPEGImageReader.readImageHeader(Native Method)
at com.sun.imageio.plugins.jpeg.JPEGImageReader.readNativeHeader(Unknown Source)
at com.sun.imageio.plugins.jpeg.JPEGImageReader.checkTablesOnly(Unknown Source)
at com.sun.imageio.plugins.jpeg.JPEGImageReader.gotoImage(Unknown Source)
at com.sun.imageio.plugins.jpeg.JPEGImageReader.readHeader(Unknown Source)
at com.sun.imageio.plugins.jpeg.JPEGImageReader.readInternal(Unknown Source)
at com.sun.imageio.plugins.jpeg.JPEGImageReader.read(Unknown Source)
at javax.imageio.ImageIO.read(Unknown Source)
at javax.imageio.ImageIO.read(Unknown Source)
at Picture.<init>(Picture.java:22)
at Test_Edge_Detector.not_main(Test_Edge_Detector.java:37)
at Test_Main.main(Test_Main.java:88)
Exception in thread "main" java.lang.RuntimeException: Could not open file: pic45.jpg
at Picture.<init>(Picture.java:27)
at Test_Edge_Detector.not_main(Test_Edge_Detector.java:37)
at Test_Main.main(Test_Main.java:88)
My question is:-
1)Where is the actual problem?Is it any kind of bug?
2)I'm using the concept of piping recently to execute the application.Can it be the cause?
When I googled I found the following informations.There is a bug in ImageIO while trying to write image file.But
I'm not sure about that it will be relevent here :-
1)from sun's bug database:-
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6247985
2)from SUN Developer Forums
http://forum.java.sun.com/thread.jspa?threadID=768917&messageID=4382833
3)from Java.NET forum(here they r getting the bug while they r using createScreenCapture() method of robot class,I am
also using that in my code)
http://forums.java.net/jive/thread.jspa?messageID=123247
4)from SUN's archieve
http://archives.java.sun.com/cgi-bin/wa?A2=ind0207&L=java-imageio-interest&D=0&P=1483
5)Here is the actual implemetation of ImageIO class.I'm getting error at 391 no. line.
http://kickjava.com/src/javax/imageio/ImageIO.java.htm
Thanks And Regards
Subhadip

Hello,
I am writng to ask a doubt I have been encountered. I have an array of Image URL's and I am downloading the images using thses URL for each index. The example for an image URL will be as follows:
http://www.firstmonday.org/issues/issue6_10/wiggins/google-3oct2001.gifIf the URL is abroken link, I am getting the exception. But if the URL is somewhat hanging (which means when u open that URL in IE or Mozilla, the statuc bar for downloading the image will be hanging).
So i want to set a timer for every link while downloading. may be 10min. My idea is if in that 10min, if code does not completes downloading the images, then ignore that link and proceed furthur.
Can u please tell me how to write this.. Please tell me any other idea to tackle this problem.
Thank you,
Chaitanya

Read and write analog fast varying signal simultaneously using Ni 6008 + vb6 code

Similar Messages

Maybe you are looking for