Xi real time tasks

Hi Xi Guru's!
I need any technical specification in xi as i have done basic scenarios, I want know how the real time objects will be in Xi, could any one send me the real time tasks spec or objects, So that it will be more help full to me to get acquainted with real time tasks.
Thank you guru's,
Mark...
[email protected]

Markiv,
Check this weblog for all the documents in XI:
/people/michal.krawczyk2/blog/2005/04/09/xi--saps-document-templates
Regards,
---Satish

Similar Messages

Real time task synchronization

I am using LabVIEW real time and I want to "trigger" a lower priority task at the end of the highest priority task if it isn't already done. What is the best solution ? I have read somewhere on NI site that the synchronisation palette doesn't guarantee determinism but unfortunately the real time fifos do not provide a blocking read call. Is there a potential real time problem when using occurences ? I would just like a simple deterministic mechanism to wake up a task if it isn't already awake.
Thanks in advance.

Monsieur,
Je vous invite à consulter la doc ci-dessous pour plus d'infos sur comment LabVIEW gère les priorités lorsque plusieurs VIs s'exécutent en parallèle.
* How Does Priority Affect the Execution of VIs?
http://digital.ni.com/public.nsf/websearch/84081F249CEF7AB7862569450074168C?OpenDocument
* How is Priority of Execution Assigned when Loading and Executing Multiple VIs in LabVIEW?
http://digital.ni.com/public.nsf/websearch/44AB5BEDC20CB43C862565D4000D9885?OpenDocument
Les RT FIFOs sont le meilleur moyen pour transférer des données entre threads (typiquement, un thread critique avec un thread normal ou lower).
Les RT FIFOs ne cassent pas le déterminisme d'une application RT contrairement aux variables locales ou globales.
La gestion de l'exécution est entièrement faite par le Scheduler du moteur LabVIEW RT. Vous n'avez pas le contrôle sur son mode de fonctionnement.
Vous n'avez pas du tout intérêt à synchroniser avec les outils de LabVIEW une tâche critique RT avec une tâche non critique car vous allez forcément casser le déterminisme de l'application RT. Vous pouvez cependant synchroniser des portions de code du VI non critique (occurence pour déclencher du code sur génération d'un événement logiciel, rendez-vous pour synchro démarrage multi-VIs, sémaphores ...).
Cordialement.
Matthieu Gourssies
National Instruments

Solaris 10 real-time support on a uniprocessor system

Hello,
I've read older documentation stating that Solaris has real-time support on a dual processor system. One of the CPUs is dedicated to the real time tasks. I was wondering
if this is an absolute requirement. Could one use Solaris 10 as a real-time OS on a uni-processor system?
Thanks for your help.
Stephen

Stephen,
Solaris is capable of running processes in real-time mode on either a uni- or multiprocessor machine. real-time mode is implemented at the scheduler level, with RT class processes layered on top of TS/IA and SYS processes. This is mostly implemented through priority levels (0-59 for TS/IA, 60-99 for SYS, 100-159 for RT [if used]). For details regarding this, pls. see priocntl(1).
Be aware of a couple of gotchas, though:
- RT processes will stay at their priority level, no matter what.
- They will not be subject to time-sliced scheduling (in fact, they won't be scheduled in normal ways, since the scheduler itself runs at SYS priority level!)
- They'll not stop running until they either voluntarily give up the CPU by means of something like swtch(), or block on a resource, or any process with an even higher priority becomes runnable.
In short, they might render your system more or less inoperable, if used without caution.
Consider it a BAD idea to put your shell into RT mode - and definitely do NOT try to run largely computational tasks (PI to the nth position, as an example) in RT mode, just to get some more performance out of your box! It won't work as you expect it.
RT is meant to run fairly short routines that require (almost ) deterministic response - such as acting on a signal from a sensor on an assembly line. It's definitely not a way to obtain better response times or outperform your peers.
Solaris, as any UNIX, is not an outright RT system - it just has some stuff built into it that could help in running it as if it were one.
Consider well what you're about to do, then reconsider ... ;) Don't say you haven't been warned.
HIH, kind regards,
- Tom

Making task execution a reality, in real-time, for critical industries

Problem
Enterprise software systems like ERP identify what needs to be done, but fail to outline how these tasks should be executed, due in large part to operational processes which are typically locked in disparate procedural documents, forms and excel spreadsheets. This approach limits the visibility into internal operations, enhancement of management by exception, and predictive analytics.
In all of industries Mobideo targets, processes are managed traditionally with ERP software where the tasks performed are manually documented, a process which is error prone and time consuming. In the Aerospace and Defense industry for example, the Federal Aviation Administration concluded that documentation is the leading contributing factor to maintenance mishaps. These errors are specifically attributed to:
Failure to follow published technical data or local instructions
Using an unauthorized procedure not referenced in the technical data
Supervisory personnel accepting non-use of technical data or failure to follow maintenance instructions.
Solution
Mobideo’s unique solution gathers granular data to capture what is happening in an operational environment in real-time, thereby optimizing performance, cost, and compliance of operational processes. It does this by uploading the smallest of business elements in the formats they are found and converting them to a mobile application. Using SAP HANA, the platform enables visibility by creating personalized applications that guide users through each job task in a step-by-step checklist. This framework ensures quality in tough working environments and confirms execution of tasks at the point of service. Core Competencies
Mobideo converges all task execution data into a unified application
Mobideo ensures compliance
Mobideo tracks granular interaction and data entry in real time
Mobideo enables rapid deployment driven from the procedures themselves
Mobideo offers Deep integration with third party enterprise applications
Watch
Watch Samuel Solomon, chairman discuss the Mobideo solution at this year’s SAPPHIRE NOW event.
SAP HANA Transforms Operations Management for Mobidio - YouTube

Problem
Enterprise software systems like ERP identify what needs to be done, but fail to outline how these tasks should be executed, due in large part to operational processes which are typically locked in disparate procedural documents, forms and excel spreadsheets. This approach limits the visibility into internal operations, enhancement of management by exception, and predictive analytics.
In all of industries Mobideo targets, processes are managed traditionally with ERP software where the tasks performed are manually documented, a process which is error prone and time consuming. In the Aerospace and Defense industry for example, the Federal Aviation Administration concluded that documentation is the leading contributing factor to maintenance mishaps. These errors are specifically attributed to:
Failure to follow published technical data or local instructions
Using an unauthorized procedure not referenced in the technical data
Supervisory personnel accepting non-use of technical data or failure to follow maintenance instructions.
Solution
Mobideo’s unique solution gathers granular data to capture what is happening in an operational environment in real-time, thereby optimizing performance, cost, and compliance of operational processes. It does this by uploading the smallest of business elements in the formats they are found and converting them to a mobile application. Using SAP HANA, the platform enables visibility by creating personalized applications that guide users through each job task in a step-by-step checklist. This framework ensures quality in tough working environments and confirms execution of tasks at the point of service. Core Competencies
Mobideo converges all task execution data into a unified application
Mobideo ensures compliance
Mobideo tracks granular interaction and data entry in real time
Mobideo enables rapid deployment driven from the procedures themselves
Mobideo offers Deep integration with third party enterprise applications
Watch
Watch Samuel Solomon, chairman discuss the Mobideo solution at this year’s SAPPHIRE NOW event.
SAP HANA Transforms Operations Management for Mobidio - YouTube

How can 2 users collaborate real time on a Pages document?

I have two computers at home: an iMac and a macbook pro. We have no problem sharing document via the wireless Timecapsule network. Recently, as we have been deep in editing documents using Pages, we were trying to find out how to configure pages so that we can both edit the same document at the same time (collaboratively) and see each other's edits in real time as we progress. Google docs has this option but it's rather slow.
Is there an option to do this in Pages on a local network?
If no, do you know of any other Apple programs that let you collaborate on text document in real time?
Thank you.

Welcome to the forums!
Pages cannot do what you want. Most word processors can't. However, there are a few solution that can. SubEthaEdit is a collaborative text editor for the Mac, so it can handle this kind of task. It has received pretty positive reviews. You might also check out Collaborate, UNA (although this is more intended for software development), and Gobby.

Help needed with CVI real time

Hi,
I am new to CVI real time and need help related to this. I will explain my scenario:
1. I have few configuration files (INI). Need to validate the files (range checking..etc) during start of the application.
2. When user clicks "START" in the user interface on the host machine, I need to generate outputs (analogs/discretes...) based on the settings in the config file and read some inputs from other instruments. ( I/O tasks like generating outputs/reading inputs i am planning to perform in RT side)
3. From the user interface, user can also change the config files. if user changes the files, again file validation needs to be performed. After changing the files, if user clicks START, need to take the newly enetered config files to perfom I/O tasks.
4. I am NOT using reflective memory for my application.
I am confused in the following area:
1. File validation during startup , do i have to perform on both host and RT side?????
2. if configuration files are changed in the host side by the user, how i have to send this latest file names to RT??? I think i should not send file names, i need to read from the file and its contents i need to pass to RT....Pls correct me , I am not sure about this....
3. If I have to send file contents to the RT, how I have to do that....means i have to use structures,..???
Please guide me. Any help would be highly appreciated.
Regards,
haari
Solved!
Go to Solution.

Hey haari,
1. File validation during startup , do I have to perform on both host and RT side?????
This depends on the full range of responsibility for the INI files. If they are all needed simply to change what the I/O tasks are for, then you would technically only need to validate the INI file contents on the RT side. You could, however, validate on both sides if you wanted to. However, I would probably set it up such that I send a validation command to the target, have the target run a component of the code that validates the INI contents based on how I instructed it, and then return a message that says whether or not it met the requirements I specified. However, if you are concerned with offloading that process to the user desktop (instead weighing down the RT controller performance), you could FTP the file off of the controller and perform the validation process on the host side.
2. if configuration files are changed in the host side by the user, how i have to send this latest file names to RT??? I think i should not send file names, i need to read from the file and its contents i need to pass to RT....Pls correct me , I am not sure about this....
You can send them to the target over FTP. This can be done programmatically, through MAX, command window, or a Web browser.
3. If I have to send file contents to the RT, how I have to do that....means i have to use structures,..???
This is basically addressed in answer to question two. You would not need another structure in your RT code to handle the FTP receive component as this is handled by the FTP Client/Server communication. However, in the event that you successfully FTP a file to the target, you should likely send a message from the host to the target so that the target can respond accordingly and reload the file, reestablish the I/O values, run an idle procedure, or do whatever you like.
Hope this helps. Have a great day!
Tim A.
National Instruments

In a Real time project what would be the agent assignment attribute setting

Dear Experts,
I have never worked on a workflow project. I have been only practising workflow on a IDES system. I would like to know in a real live production system what settings do we use when we define the agent assignment at the task level? Do we set the attribute as GENERAL TASK always?
To be more specific as in the task attributes we have many options like
GENERAL TASK
GENERAL FORWARDING ALLOWED,
GENERAL FORWARDING NOT ALLOWED AND
FORWARDING NOT ALLOWED.
From the first three options which is most generally used in a real time projects?
AND
is it necessary to always set the attribute as GENERAL TASK before transporting the workflow definition to other systems from the development system?
appreciate your help on the same.
cheers
chky

Hello Learner,
It depends on the requirement, but in most of the cases we assign the task as general task.
To have some more information on the various attributes,
·        General task
If you define a task as a general task, all users can execute the task. This is useful if the task is used in a workflow and you only want to define the recipients in the step definition. A recipient can forward associated work items to all users.
Work items whose tasks are defined as general tasks and for which no responsible agents or default rules are defined are offered to all users of the SAP System for execution in their Business Workplaces.
·        General forwarding allowed
A work item that represents a task with this property can be forwarded by one of its recipients to all users, even if they are not possible agents of the task.
·        General forwarding not allowed
A work item that represents a task with this property can be forwarded by one of its recipients only to the possible agents of the task.
·        Forwarding not allowed
A work item that represents a task with this property cannot be forwarded by one of its recipients.
Hope this will help.
Regards,
Sam

To develop an VI to aquire data of thermocouples from a remote chamber in labVIEW real time, should use NIDAQ or NIDAQmx?

Hai
I need to develop an VI to aquire data at real time. Am using LabVIEW RT as the OS and i need to know, if i can use NIDAQ 7.0 or should i use NIDAQmx? what is the diffrence between the two? is it just that NIDAQmx makes job simpler?
Also can anybody please tell me, how to access a channel in labVIEW? am not clear about the path to follow to get the physical channel as a virtual channel on the LabVIEW.
I am using a 8186 PXI with labVIEW RT and a SCXI, with both scxi and daq card on the same chassis.
the development will be done on Windows XP which will be the host machine.
Thanx in advance for any answers
Arun

Arun,
DAQmx is our new Data Acquisition driver and should be considered as the primary option when writing new applications because of supportability in the future.
DAQmx does make Data Acquisition tasks much simpler, abstracting many of the board implementation details and giving you a common API for 99% of the tasks you might want to accomplish.
There are a couple of minimum requirements for using DAQmx on LabVIEW Real Time:
- You will need LabVIEW Real-Time 7.1 (or higher)
- You will need DAQmx 7.2 (or higher)
These requirements are mentioned in the following Knowledgebase:
Is NI-DAQmx Supported in LabVIEW Real-Time?
The other thing you might want to make sure of is that DAQmx supports the DAQ hardware you already have or are planning to use. DAQmx does support most of the existing DAQ and SCXI hardware products, and reading thermocouples should become a very simple task.
With DAQmx you can use physical channels, Global Channels (Aliases for preconfigured physical channels, equivalent to the Traditional DAQ Virtual Channels) or DAQmx Tasks (Preconfigured Data Acquisition tasks that include channel, timing and triggering information). A good place to start to learn about these features could be:
Advantages of NI-DAQmx
The following link might be useful to check Hardware support:
http://www.ni.com/support/daq/versions.htm
The driver can be downloaded by following these links:
ni.com -> Support -> Drivers and Updates -> Current Software Versions -> Multifunction DAQ -> NI-DAQ Version 7.3 for Windows 2000/NT/XP
This includes the latest version of DAQmx and our Traditional DAQ driver. Please note that DAQmx base is also listed but that's our Register-Level Programming (RLP) driver, which provides DAQ support for previously unsupported platforms.
I hope this helps,
Alejandro

Scheduling in Real-Time Java

Hello,
I have some questions concerning how scheduling in fact is intended to be performed in a RTSJ based Real-Time Java System.
As far as I understood, RTSJ requires pre-emptive priority-based dispatching of Schedulable objects.
This means that the execution eligibility of a schedulable entity is mainly its priority.
That causality is reflected within the specification with the (one-and-only specified) PriorityScheduler, which is the base scheduler for actual Real-Time Java applications.
Furthermore, there is a notion of extensibility of that PriorityScheduler described by RTSJ,
in order to provide further scheduling mechanims and feasibility analysis algorithms (please correct me if there are any wrong assumptions).
This is the point, where everything becomes really weird to me ...
As far as I could investigate, in most RTSJ implementations based on a POSIX compliant system underneath (like Java RTS does on RTLinux or Solaris)
each (Realtime)JavaThread is mapped 1-to-1 to a light-weight process on the operating system level (e.g. a pthread).
So far, we have no "green threads" within the JVM, but real LWPs scheduled by the OS.
The difference between "normal" and "real-time" threads lies in the scheduling policy used for that mapping.
While normal Java threads probably map to SCHED_RR or SCHED_OTHER, real-time threads are scheduled by the OS via the SCHED_FIFO policy in order to achieve a better real-time predictability.
However, the OS's scheduling mechanisms automatically make decisions about the right positioning of a LWP within an appropriate run-queue, due to thread's preemption, blocking or release (even dynamic priority changes) activities and its scheduling policy.
That's exactly why I ask myself, what is the need of a Scheduler representation within a JVM?
Furthermore, how a Scheduler extension is able to incorporate with the threading model and the underlying scheduling mechanisms of the OS?
One point could be a situation where a real-time JVM runs directly on top of the bare hardware and has to perform scheduling decisions on its own.
The Scheduler API could then be understood as an extension mechanism of a kind of JVM-intern scheduler (e.g. the PriorityScheduler), thereby allowing scheduling decisions to be made even in user defined Scheduler implementations.
A similar use case for an OS-based scenario could be if a JVM is intended to pass scheduling/threading routines of the underlying OS (eg. a part of the POSIX API)
up to the Java application level in order to provide the opportunity for a kind of application defined scheduling (like e.g. in the MaRTE OS).
Unfortunatelly, after introspecting the RTSJ API, both conclusions seem to me to be wrong.
So far, Java RTS seems not to provide any mechanism for reaction on scheduling events/decisions, neither intra-JVM nor from an underlying OS outside of the JVM.
Furthermore, there is no notion for incorporation with the base PriorityScheduler for making extended scheduling decisions.
I hope this post could bring me more light into the scheduling idea behind Real-Time Java systems as intnded by the RTSJ.
Sincerely,
Vladimir

Vladimir.Nikolov wrote:
That means, that a scheduling policy different to PriorityScheduler can only be assigned to a Schedulable object if it is supported by the OS and the JVM?Well it has to be supported by that implementation of the RTSJ. Howe that is done - ie whether it requires OS support - depends on that VM, the OS and the actual scheduling policy.
It also seems that at the current state of the art the PriorityScheduler representative within the JVM is intended only for manipulating a feasibility set of Schedulable objects (supporting online feasibility analysis)?
However, since user-defined scheduling is not intended by the specification, applications have to rely on the feasibility analysis based on the underlying/supported scheduling mechanisms.
Thus, in the current Java RTS implementation this would be the "default" feasibility mechanism based on the PriorityScheduler.
Unfortunatelly I can not figure out the need of maintaining a feasibility set, since feasibility, as specified for the PriorityScheduler, is a simple asumption that we have "an adequatly fast machine to handle the periodic and sporadic load"?
I actually assumed that feasibility analysis performs real cost budgeting taking into account deadlines and so on, but it seems to be specified simply to make a negative statement always when aperiodic tasks are involved ?The RTSJ scheduling framework provides support for feasibility analysis by defining the admission control methods eg setXXXIfFeasible. However the RTSJ does not, and can not, mandate any non-trivial feasibility algorithm because in simple terms no such general algorithms exist. There are some static feasibility tests in the literature and you could apply those offline to your application (assuming you can find the values of all the "magic" numbers in such formulae - which is generally not the case). At present the RTSJ doesn't support even these simple feasibility tests because blocking-time is not recorded in the release parameters - something being addressed in RTSJ 1.1. In any case unless there is a pluggable framework for feasibility tests it would be a waste of time for VMs to implement them given they can (more) easily be done offline using other tools.
Only dynamic admission control is really of interest and as far as I am aware no such general dynamic admission control policies exist (anything you find in the literature is very context specific). So it is left up to an implementation as to whether they try and define dynamic admission control algorithms - and so far none have because they don't have one.
In "Getting More Flexible Scheduling in the RTSJ" Wellings and Zerzelidis propose some (more or less) "minor" extensions to the RTSJ API in order to enable hierarchical scheduling within the fixed priority framework.
Since Andy Wellings is a member of the RTSJ Technical Interpretation Committee, is there any attempt to evolve the specification in a similar direction as described above, in order to support more flexible scheduling mechanisms and feasibility analysis?If there is ever a RTSJ 2.0 then more sophisticated scheduling support is one of the items on the wishlist. But there's no guarantee there ever will be a RTSJ 2.0
David Holmes

Fico interview questions and Real time tickets with resoving details

MODERATOR: Do not post (or request) email address or links to copyrighted or confidential information on these forums. If you do, the thread will be LOCKED and all points UNASSIGNED.
hi sap gurus
i have done sap-fico iam in job trails. can any body help me Fico interview questions and Real time tickets with resoving details
regards
prasad.v
Edited by: chinna prasad on Jun 5, 2008 4:10 PM

Hello Prasad,
Before attending interviews.....First you need to understand general things like CV writing, projects, sub modules etc., you should be gain knowledge on these concepts then you can move further.
1. CV 2.Projects 3.your strenths in sap (reading..reading...reading....practice...practice...practice)
2.you please interact with your friends who is on trails, then you can get more information like interview process, methodology, technical etc.,
I am sending some real time interview tech questions which will useful for you.
Questions:
1.When tickets are raised by end users who will give priority? After resolve the tickets who will close the status?
2.In real time at a time how many normal periods, special periods, MM periods we can open?
3.What is client dependant & Independent?
4.How to transport configuration settings from one client to another client or production client, which tools we can use for transport?
5.Why we donu2019t assign business area to company code?
6.What is the difference between General GL A/c, Control A/c, Reconciliation A/c & Offsetting A/c?
Answers:
1.The priority is generally decided by the Coordinator on the client side. After tickets are resolved, they will have to be closed by the coordinator on the customer site
2. In FI as many as you wants. In MM only 2 (current month + previous
3.Certain tables and customizations made in one client will affect the other clients also - then it is cross client i.e, client dependent. While if the changes made in one client has no impact on the other client - it is said to be client independent
4.Transports from one server to the other can be made with the help of transport requests. When a configuration is done the system generates a request number. First release the task and then release the request. Use TC-SE10 / SE09, SE09: workbench transport; SE10: customizing transport. But currently no such difference actually exists.
5.because in case of multiple company codes, same business area can be used across company codes. Business area is cross company code, means it is not confined to one company code thatu2019s why we don't assign BA to any of the company codes. It is client dependant, not company code dependant. We can pass values from one company code to any of the BA in that client.
6.General GL Account are those used for standard posting like for example Income and Expenses Accounts
- Control Account are basically used for reconciliation between modules like FI and CO, to ensure that both the modules are in sync.
- Reconciliation Account are those specific covering ADK (A-Assets, D-Customer, K-Vendor). For example a Customer Master would be mapped to a Bills Receivable Reconciliation Account and any transaction that needs to be posted are done against the customer code.
- Offsetting Account are used for variety of reasons and few examples are Intercompany Postings, at the time of Implementation when TB and Balance sheet are uploaded would be offsetted against a dummy account.
All the best.....dont forget and pl assign points if useful and if u have any querries pl revert back
thanks
Anil

How to get signal from analog input and send it to analog output (real-time)

Hi everyone,
I am doing simple task in Visual C++ and I am using PCI-6221(37 pin).
Basically, I want to send same signal from 'analog input' to 'analog output'
at the same time (almost), to make it real-time application.
Can someone please provide me sample program.
I would appreciate if you could provide me with the good tutorial which explains
step by step everything about programing NI-DAQmx for C/C++.
Best Regards,
Khassan
Solved!
Go to Solution.

This is my code in C++, you can optimize it if it looks too messy. This code reads signal from analog input and outputs it through analog output.
To make this code work additional include directories and library directories must be added from NI.
I hope it helps someone.
#include <stdio.h>
#include <conio.h>
#include "NIDAQmx.h"
#include <math.h>
#define DAQmxErrChk(functionCall) { if( DAQmxFailed(error=(functionCall)) ) { goto Error; } }
int main(int argc, char *argv[])
int32 error=0;
TaskHandle taskHandleRead=0,taskHandleWrite=0;
int32 read=0;
float64 dataRead[1000];
char errBuffRead[2048]={'\0'};
char errBuffWrite[2048]={'\0'};
bool32 done=0;
int32 written;
DAQmxErrChk (DAQmxCreateTask("",&taskHandleRead));
DAQmxErrChk (DAQmxCreateAIVoltageChan(taskHandleRead,"Dev1/ai0","",DAQmx_Val_Cfg_Default,-10.0,10.0,DAQmx_Val_Volts,NULL));
DAQmxErrChk (DAQmxCfgSampClkTiming(taskHandleRead,"",100.0,DAQmx_Val_Rising,DAQmx_Val_ContSamps,0));
DAQmxErrChk (DAQmxCreateTask("",&taskHandleWrite));
DAQmxErrChk (DAQmxCreateAOVoltageChan(taskHandleWrite,"Dev1/ao0","",-10.0,10.0,DAQmx_Val_Volts,NULL));
DAQmxErrChk (DAQmxCfgSampClkTiming(taskHandleWrite,"ai/SampleClock",100.0,DAQmx_Val_Rising,DAQmx_Val_ContSamps,1000));
DAQmxErrChk (DAQmxStartTask(taskHandleRead));
DAQmxErrChk (DAQmxStartTask(taskHandleWrite));
while( !done && !_kbhit() )
DAQmxErrChk (DAQmxReadAnalogF64(taskHandleRead,1,10,DAQmx_Val_GroupByScanNumber,dataRead,1000,&read,NULL));
DAQmxErrChk (DAQmxWriteAnalogF64(taskHandleWrite,read,0,10.0,DAQmx_Val_GroupByChannel,dataRead,&written,NULL));
_getch();
Error:
if( DAQmxFailed(error) )
DAQmxGetExtendedErrorInfo(errBuffRead,2048);
DAQmxGetExtendedErrorInfo(errBuffWrite,2048);
if( taskHandleRead!=0 )
DAQmxStopTask(taskHandleRead);
DAQmxClearTask(taskHandleRead);
if( taskHandleWrite!=0 )
DAQmxStopTask(taskHandleWrite);
DAQmxClearTask(taskHandleWrite);
if( DAQmxFailed(error) ){
printf("DAQmx Error: %s\n",errBuffRead);
printf("DAQmx Error: %s\n",errBuffWrite);
printf("End of program, press Enter key to quit\n");
getchar();
return 0;

How to determine time value of a .wav file in real time as it plays?

Hi all.
I need to build a vi in which a .wav sound file is represented in a Waveform graph, and at the same time, I want to play that file, and have a vertical cursor line running along the Waveform graph, in order to have a visual representation of where the sound track is, in terms of time.
Making the .wav file to appear graphicaly on a Waveform graph was an easy task to do, but then, I was´nt able to extract the time information of that .wav file, at the same time that this file is being played.
This is a very common situation in music players, video players etc, where some kind of graphical artifact, represents in real time where the track is while it plays.

Hi, this is the first ActiveX control I have played with but its really cool.
I read this first: -
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/wmplay10/mmp_sdk/iwmpcontrolsinterface.asp
Which covers "The IWMPControls interface provides a way to manipulate the playback of a media item."
Then built the attached sample.
It should now be straight forward to attach the position information shown to a graph control cursor postion.
You will need to set a file of your own choosing in the VI first.
Let us all know if this is what you wanted.
Attachments:
mediaplayer current play position demo.vi ‏39 KB

Attempt to build real-time application failed

When I try to build my real-time application in order to deploy it to a crio device, it fails. I can run the program just fine by opening it and clicking run. It can deploy and run all day that way, but it needs the computer that way too. So I need to be able to build and deploy it. When I do a build preview it completes just fine with no errors. I have set the program I want to start up as the startup and my subVIs virtual folder under always include. This is typical procedure for deploying projects to the crio.
When it crashes I am getting an error:
The build was unsuccessful.
Possible reasons
An error occurred while saving the following file:
C:\Program Files\National Instruments\LabVIEW 2009\vi.lib\rvi\ClientSDK\Core\ModuleGeneration\CommunicationInterfaceUtility\niFpgaDmaChannelImplementation.ctl
Invoke Node in AB_Source_VI.lvclass:Close_Reference.vi->AB_Build.lvclass:Copy_Files.vi->AB_Application.lvclass:Copy_Files.vi->AB_RTEXE.lvclass:Copy_Files.vi->AB_Build.lvclass:Build.vi->AB_Application.lvclass:Build.vi->AB_RTEXE.lvclass:Build.vi->AB_Build.lvclass:Build_from_Wizard.vi->AB_UI_Frmwk_Build.lvclass:Build.vi->AB_UI_FRAMEWORK.vi->AB_CreateNewWizard_Invoke_CORE.vi->RTBUIP_CreateNewWizard_Invoke.vi->RTBUIP_CreateNewWizard_Invoke.vi.ProxyCaller
<APPEND>
Method Name: <b>Save:Target Instrument</b>
I put in a service request (Reference#7259553) but I am just not getting help fast enough. I am on a real deadline here and I just sort of expected the application builder to work like it has always done. I have done this a million times with other applications and never had an issue like this.
Thanks in advance for your help guys.
[will work for kudos]
Solved!
Go to Solution.

With the fantastic help of applications engineer Will Schoettler, we were able to solve the problem.
1. First we tried creating a new project file from scratch, adding all the files and compiling the fpga. Same error.
2. Next we made individual builds deploying each subvi individually to see if one of them was causing the error. Each built without a problem.
3. I tried to create a new build for the main crio program and tweek the settings. Instead of manually adding the subvi and variable library folder to the 'always include' section of the build option, I simply added the main VI to the startup programs list and was going to let LabVIEW figure out which VIs to add. For some reason this gave me a more verbose error explanation and gave the following reason as the last sentance in the error explanation
"Due to operating system limitations, LabVIEW cannot create the folder because its complete path contains too many characters."
I moved the project folder to c:/ , fixed the broken references in the project, and it built the VI and deployed it just fine.
The builder creates a directory with a really long path name within your project folder, so if you have your project folder deep in your directory tree it will attempt to create files with paths too big for windows to handle.
Mad Kudos to Will Schoettler the app engineer for such a potent and thorough troubleshooting task list of things to try that lead me straight to the solution. I am glad it was something so simple and not some form of file corruption or something wrong with my code.
Thanks for trying to help guys.
[will work for kudos]

Pci 6259 real time windows target matlab

Hello everyone,
I want to buy 1 NI PCI-6259, 2 Cables(SHC68-68-EPM Cable (2m)) and 2
Connector Blocks (SCB-68 - Shielded).
Would you please tell me do I need another hardwarefor
this product?
I want to this product with Matlab Real Time Windows Target.
Would you please tell me do I need what software for
this product to work with Matlab Real Time Windows Target?
Best regards,
Naser

Hello Olivia
I want to measure impedance of a device.
I want to generate a chirp signal and measure impedance this
device by NI PCI 6259.
My frequency is about 10KHZ to 300KH.
I use Windows xp for this task. I want to use Matlab software.
So, for MAtlab software only DAQmx
driver is needed?
Best regards
Naser

DPC spike at Windows automatic maintenance startup. Can not leave the computer alone processing real-time streams.

This is what happens when I leave the computer idle for a while and the Windows automatic maintenance starts:
Driver file Description ISR count DPC count Highest execution (ms) Total execution (ms)
ntoskrnl.exe NT Kernel & System 0 50764 0,235854
332,950426
A DPC spike is generated by ntoskrnl.exe causing drop outs in real-time streams.
JTS

Hi Fjtorsol,
We hope your issue has been resolved, if you've found solution by yourself. you could share with us and we will mark it as answer.
This high Deferred Procedure Call (DPC) latencies are usually caused by certain drivers, if it is caused by automatic maintenance, please re-check your task schedule which is marked as “when computer is idle”. As what has been suggested by MVP ZigZag, please
use the Microsoft Windows Performance Analyzer from the Windows Assessment and Deployment Kit (ADK) to identify the cause of any DPC latency spikes.
https://www.microsoft.com/en-gb/download/details.aspx?id=39982
DPC CPU Usage Summary Table will open containing a list of drivers/program. This list is already correctly sorted (by the Actual Duration column). The process on the very top of the list is therefore likely to be the cause of your problem.
Regards
D. Wu
Please remember to mark the replies as answers if they help, and unmark the answers if they provide no help. If you have feedback for TechNet Support, contact [email protected]

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