Tech Off

DMX512, serialport and .Net

ZippyV — Sun, 22 Nov 2009 19:06:46 GMT

I've got this device laying around in my room and last week I decided to try if I can control it using vb.net. The device is connected from a usb port on my laptop to the dmx port. It has a serial converter built in so Windows sees it as COM4. The problem is that my application doesn't work. I tried to implement the code based on Ujjal's DMX512 page, did I make any mistake?

[code language="vb"]

Public Sub New()
sp = New SerialPort("COM4", 250000, Parity.None, 8, StopBits.Two)
sp.Open()
End Sub

Public Sub Send(ByVal data As Byte())
'Send break time
sp.BreakState = True
Threading.Thread.Sleep(10)
sp.BreakState = False

'Send Mark After Break (MAB)
sp.Write(New Byte() {255}, 0, 1)
'Send Start Code (SC)
sp.StopBits = StopBits.Two
sp.Write(New Byte() {0}, 0, 1)

'Send dmx data
sp.Write(data, 0, data.Length)
End Sub[/code]

The byte array that gets passed in is this one:

[code language="vb"]

With lSettings
.Add(8) ' Shutter open
.Add(255) ' 100%
.Add(24) ' Color wheel (red)
.Add(0) ' Gobo selection (open)
.Add(0) ' Gobo rotation type (stop)
.Add(128) ' Pan (neutral)
.Add(128) ' Tilt (neutral)
End With[/code]

ASP.NET MVC documentation for Visual Studio 2008

rhm — Sat, 21 Nov 2009 19:49:20 GMT

Is there a download for this somewhere that I can't find. Installing ASP.NET MVC itself doesn't seem to add any documentation to the help browser in VS2008. It exists in the online MSDN library though:-

http://msdn.microsoft.com/en-us/library/system.web.mvc.aspx

I re-downloaded and did a repair with the MSI of the VS2008 SP1 documentation set just to check, and that doesn't include it.

Some of my views

siligongsi — Sat, 21 Nov 2009 16:15:48 GMT

NIKE is a good brand, I personally like it better. Not only because of the style or quality nike shoes. And it's strategy is very much appreciated. Talking about the present campaign is the brand nike, adidas, puma, and so few, but should be counted the most popular when nike had. This is a strategy they are inextricably linked.
NIKE is the final design of their products, styles, every year it is to launch a lot of popular styles out, before I go to school inside the school when a friend bought sports shoes are basically first consider the first went to Kanxia The new nike, shows that their popularity degree. NIKE shoes wear very comfortable, appropriate to relax the foot well.
NIKE can always find a good brand agency star, Michael Jordan, Kobe Bryant, James, etc. are well known biggest names. Through these stars make a lot of people tend to put on the star's feelings to the nike, produced a good effect sought after. I have bought many pairs of nike shoes, really liked. Particularly fond of nike dunk sb. In the country there are many sports brands, but it feels so good not many. These companies in many ways, with foreign brands compared to these large there are many deficiencies. But I estimate that with the continuous improvement, the domestic will emerge a lot of internationally renowned sports brand.
http://www.dunksky.com/

DataTemplate.DataType alternative in Silverlight 3

Bas — Sat, 21 Nov 2009 12:09:49 GMT

In Silverlight 3, if you declare a DataTemplate in XAML, there's no way to change the template based on the type of the bound item. In WPF, you can set the DataType property on the DataTemplate, but that property doesn't exist in SL3. Is there any sort of alternative to this? Perhaps an event that gets fired each time an item gets bound, so that you can set the DataTemplate manually in code? I need this functionality in an SL3 application, but the way it looks now, if I want to change the template based on the item's type I have to drop databinding altogether and just manually iterate through an array and add the items myself. Any way around this?

Jumping in the .net bandwagon

cro — Fri, 20 Nov 2009 20:54:22 GMT

I know that I'm very late, but we are jumping in the .net bandwagon. I have done some little app in C# but I would like tutorials for professional app (localization, save the toolbars and windows state, etc.). I've search the msdn site, but it is hard to find informations (maybe it is just me). So any book recommandation, sites, webcast, or old pcd videos would be great.

I'm moving from C++/MFC/Stingray/MapX/Vertical Mapper to C#/MSChart/MapXtreme/Vertical Mapper.

Thanks.

Good .Net 2.0 tutorial for SQL Compact (C#)

ManipUni — Fri, 20 Nov 2009 19:28:08 GMT

Hey,

Has anyone got a link to a fairly good Microsoft SQL Compact - ASP.net / 2.0 tutorial (hint: cannot use Linq or other new 3-3.5 tech). It doesn't need to be a ground breaking tutorial, just need to get a lot of the back-end pipes hooked up rather than SQL/call logic.

PS - I did google it but found there is at least half a dozen ways to hook into SQL Compact and a lot of information either .Net 1.0 or 3.5, little around the 2.0 mark.

Does this code have a race condition?

Sven Groot — Fri, 20 Nov 2009 08:46:31 GMT

Ok, this is a tough one. I basically spent all of yesterday attacking this from every angle I could think of, but I'm still not entirely convinced that there's a race condition here. I think there is one. One that's not easy to circumvent without introducing some other issues. I would however like to get some additional thoughts on the issue.

The situation is this: we have what on the surface is a basic producer-consumer pattern. Items are added to a queue and processed by one or more worker threads. However, the number of worker threads is flexible; if more are needed they will be started (up to a limit). If a worker thread sits idle for too long, it will quit.

Here's the code (it's not my code, but I've sanitized it and removed anything not relevant to the problem):

[code language="C#"]public class ItemProcessor
{
    private const int _maxWorkers = 100;
    private const int _workerWaitTime = 20000; // ms
    private readonly Queue<string> _work = new Queue<string>();

private int _runningThreads;
private int _availableThreads;

    public bool AddItem(string item)
    {
        if( item == null )
            throw new ArgumentNullException("item");

        lock( _work )
        {
            if( _availableThreads > 0 )
            {
                --_availableThreads;
                _work.Enqueue(item);
                Monitor.Pulse(_work);
                return true;
            }
            else if( _runningThreads < _maxWorkers )
            {
                _work.Enqueue(item);
                Thread worker = new Thread(WorkerThread);
                worker.IsBackground = true;
                ++_runningThreads;
                worker.Start();
                return true;
            }
        }

return false;
}

    private void WorkerThread()
    {
        while( true )
        {
            string work = null;
            lock( _work )
            {
                do
                {
                    if( _work.Count > 0 )
                        work = _work.Dequeue();
                    else
                    {
                        ++_availableThreads;
                        if( !Monitor.Wait(_work, _workerWaitTime) )
                        {
                            if( _work.Count > 0 )
                            {
                                // Work added as we timed out
                                work = _work.Dequeue();
                            }
                            else
                            {
                                --_availableThreads;
                                --_runningThreads;
                                return;
                            }
                        }
                    }
                } while( work == null );
            }

            // Code to process the item goes here; omitted for brevity.
        }
    }
}[/code]

Two somewhat interesting decisions were taken here. First, _availableThreads is decremented in the AddItem method; this is done to ensure that no other call to AddItem can think there are available workers while there are items waiting in the queue. Second, the worker threads will pick up work, even if the Monitor.Work call timed out. This is done to make sure that if there is only one thread and it timed out just as an item was being added this item isn't "lost" (it would sit in the queue until some other item comes in and starts a new thread).

Now here's the problem: suppose some thread gets the lock in AddItems. It sees _availableThreads > 0 and calls Monitor.Pulse. A thread receives the signal and is moved to the ready queue (for that thread, Monitor.Wait will return true). However, before that thread runs, another thread had just timed out and manages to acquire the lock first. This timed out thread will pick up the work, process it, and continue. The thread that was pulsed will see the queue is empty, loop around and continue. End result: _availableThreads got decremented once (in AddItem), and incremented twice (in both the timed out and pulsed thread) and is no longer correct.

However, we can't just decrement _availableThreads if the Wait call timed out, since if Monitor.Pulse didn't wake up any thread, you wouldn't want to do that. There is no way to tell if Monitor.Pulse actually woke up some thread.

There are probably some ways to correct this problem, but for now I'm simply interested in this: am I right there is a problem? Can this scenario (a timed out thread running in between a call to Monitor.Pulse and the pulsed thread getting the lock) actually happen? I can find nothing in the documentation of the Monitor class that says it couldn't, but maybe I'm missing something.

Any insight appreciated.

Restarting graphical mode

Dekonega — Thu, 19 Nov 2009 15:48:17 GMT

Does Windows (Vista, Seven or Server 2008) have anything close to X11's ctrl+alt+backspace which restarts the graphical mode? Thanks.

Oracle query question

qwert231 — Mon, 16 Nov 2009 17:08:25 GMT

I'm adding an Oracle SQL query to an app that already handles one Oracle query correctly.

I have this query string:

SELECT RSIPLATE.DEALER.NAME AS BUSINESSNAME, RSIPLATE.DEALER.AREA_CODE || '-' || SUBSTR(RSIPLATE.DEALER.PHONE_NUMBER, 1, 3) || '-' || SUBSTR(RSIPLATE.DEALER.PHONE_NUMBER, 4, 4) AS BUSINESSPHONE, SUBSTR(RSIPLATE.ADDRESS.ADDRESS_LINE1, 1, 40) AS ADDRESSLINE1, '' AS ADDRESSLINE2, RSIPLATE.ADDRESS.CITY_NAME AS CITY, RSIPLATE.ADDRESS.STATE_CODE AS STATE, SUBSTR(RSIPLATE.ADDRESS.ZIP_CODE, 1, 5) AS POSTALCODE FROM RSIPLATE.DEALER INNER JOIN RSIPLATE.ADDRESS ON RSIPLATE.DEALER.ADDRESS_SET_ID = RSIPLATE.ADDRESS.ADDRESS_SET_ID WHERE RSIPLATE.DEALER.ACTIVE_IND = 'Y' AND RSIPLATE.DEALER.ACCOUNT_NUMBER NOT LIKE '%B%' AND RSIPLATE.ADDRESS.ADDRESS_TYPE = 2 AND SUBSTR(RSIPLATE.DEALER.ACCOUNT_NUMBER, 1, 2) = :CountyPK ORDER BY City, BusinessName

which works.

In my code I have this line:

ListingDataAdapter.SelectCommand.Parameters.Add(

New OracleParameter("CountyPK", CountyPK.ToString("00")))

I have a second query string:

SELECT rsiplate.OWNER.work_area_code||'-'||SUBSTR(rsiplate.OWNER.work_phone_number, 1, 3)||'-'||SUBSTR(rsiplate.OWNER.work_phone_number, 4, 4) AS BUSINESSPHONE, trim(rsiplate.OWNER.first_name||' '||rsiplate.OWNER.middle_name||' '||rsiplate.OWNER.last_name) AS BUSINESSNAME, rsiplate.ADDRESS.address_line1 AS ADDRESSLINE1, rsiplate.ADDRESS.address_line2 AS ADDRESSLINE2, rsiplate.ADDRESS.city_name AS CITY, rsiplate.ADDRESS.state_code AS STATE, SUBSTR(rsiplate.ADDRESS.zip_code, 1, 5) AS POSTALCODE FROM rsiplate.WATERCRAFT_MASTER, rsiplate.WATERCRAFT_CURRENT, rsiplate.WATERCRAFT_REGIST_CURRENT, rsiplate.OWNER, rsiplate.WATERCRAFT_OWNER_CURRENT, rsiplate.ADDRESS WHERE rsiplate.WATERCRAFT_MASTER.WATERCRAFT_ID = rsiplate.WATERCRAFT_CURRENT.WATERCRAFT_ID AND rsiplate.WATERCRAFT_MASTER.LF_WATERCRAFT_REGIST_ORDER = rsiplate.WATERCRAFT_REGIST_CURRENT.WATERCRAFT_REGIST_ORDER AND rsiplate.WATERCRAFT_MASTER.LF_WATERCRAFT_ORDER = rsiplate.WATERCRAFT_CURRENT.WATERCRAFT_ORDER AND rsiplate.WATERCRAFT_MASTER.watercraft_id = rsiplate.WATERCRAFT_REGIST_CURRENT.watercraft_id and rsiplate.WATERCRAFT_MASTER.watercraft_id = rsiplate.WATERCRAFT_OWNER_CURRENT.watercraft_id and rsiplate.WATERCRAFT_OWNER_CURRENT.owner_id = rsiplate.OWNER.owner_id and rsiplate.WATERCRAFT_MASTER.watercraft_owner_group = rsiplate.WATERCRAFT_OWNER_CURRENT.watercraft_owner_group and rsiplate.ADDRESS.address_set_id = rsiplate.OWNER.address_set_id and rsiplate.WATERCRAFT_MASTER.data_status_code = 1 and rsiplate.WATERCRAFT_OWNER_CURRENT.watercraft_owner_order = 1 and rsiplate.WATERCRAFT_REGIST_CURRENT.REGIST_EXPIRATION_DATE >= SYSDATE AND rsiplate.WATERCRAFT_CURRENT.WATERCRAFT_USE_CODE = 3 AND rsiplate.ADDRESS.COUNTY_NUMBER = :CountyPK GROUP BY rsiplate.OWNER.work_area_code, rsiplate.OWNER.work_phone_number, rsiplate.OWNER.first_name, rsiplate.OWNER.middle_name, rsiplate.OWNER.last_name, rsiplate.ADDRESS.address_line1, rsiplate.ADDRESS.address_line2, rsiplate.ADDRESS.city_name, rsiplate.ADDRESS.state_code, rsiplate.ADDRESS.zip_code;

which uses the same code line. Yet I get this message:

ORA-00911: invalid character

What am I doing wrong?

Getting a Security.Exception error in ASP.NET

Doctor Who — Sun, 15 Nov 2009 01:18:19 GMT

I've been reconstructing my VS 2008 development environment on my new Windows 7 machine, after my Vista machine died. Its working for the most part, except that none of my ASP.NET apps that use the AJAX Toolkit are working, on my Win 7 machine. For example, I am getting the following error message when I attempt to run access a page that has some AJAX Toolkit controls on it:

Security Exception

Description: The application attempted to perform an operation not allowed by the security policy. To grant this application the required permission please contact your system administrator or change the application's trust level in the configuration file.

Exception Details: System.Security.SecurityException: Request for the permission of type 'System.Web.AspNetHostingPermission, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:


[SecurityException: Request for the permission of type 'System.Web.AspNetHostingPermission, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed.]
   System.Reflection.Assembly._GetType(String name, Boolean throwOnError, Boolean ignoreCase) +0

now, I'm not entirely sure what I've done wrong. When I was setting up my new Windows 7 system I installed the developer edition of SQL Server 2008, but only that (I was advised to not install any of the SQL Server Express editions). Then I installed VS 2008 Pro. Next I downloaded the AJAX Toolkit from off of www.asp.net's website. What have I done wrong? Should I have installed some sort of SQL Server Express edition (either 2005 or 2008)?

Cryptography

Prakash Chidambaram — Sat, 14 Nov 2009 06:03:58 GMT

What is Cryptography ? How to encrypt & decrypt images with informations ??

Looking for samples..

Thanks in Advance

Can Linq to Xml create xhtml?

ScanIAm — Fri, 13 Nov 2009 21:12:44 GMT

I've done a good bit of google-bing investigative work, and I've come to the conclusion that I must be an idiot.

Our hope was that we could generate the xhtml document within an XDocument and then spit it out, but it appears that entities (  for example) won't work right.

If we put an actual non-breaking space character inside the document, it never get's converted into   on the output, so downstream processing cannot handle it.

If we, instead, put   characters int the document, it turns into &nbsp; which, I assure you, ain't right.

The only solution weve come up with is to fix this after writing the contents to a string and replacing the &nbsp; with  .

This seems a bit of a hack, though, so I was wondering if anyone else has had any luck with this?

Wake up Threads

Prakash Chidambaram — Fri, 13 Nov 2009 05:39:22 GMT

How to revoke the sleeping threads???

Ex. System.Threading.Thread.Sleep(15000); //it sleep for some time... before the time ends,i need to wakeup the thread..

How ????

Thanks in Advance

Wake up Threads

Prakash Chidambaram — Fri, 13 Nov 2009 05:34:56 GMT

How to revoke the sleeping threads.... ???

Ex.

Threading.Thread.Sleep(10000); // it sleep for some time,before the time ends i need to wake up the thread. How ???

Thanks in Advance

Duplicate Active Directory Security rules in ACLs

W3bbo — Fri, 13 Nov 2009 00:48:54 GMT

In one of my domains, a lot of objects seem to have duplicate (and seemingly empty) security rules set up.

For instance, the root of my domain "company.com" has "ENTERPRISE DOMAIN CONTROLLERS" down 9 times. The first 5 times have different permissions put down ("Replicating directory changes...", "Replication synchronization", "Manage replication topology", etc) but the last 4 have nothing applied.

Other groups are down with nothing marked for them, like "Exchange Recipient Administrators" and "Exchange Servers" (both the Properties and Object security list is empty.

Is it safe to delete these empty rules and might it help performance? I ask because I need to set some custom security on some child OUs but that requires copying the inherited security, which ADUC warns against because there's 41 rules to apply.

Cancel pattern for webservices

section31 — Thu, 12 Nov 2009 02:11:19 GMT

Hi folks,

I'm doing a lot of Silverlight + WCF work in the last time and I'm just wondering whether there is specific approach to support cancelation of long running web service calls. In a current scenario I have list of items where the user can select from. With the selection an item, the a webservice get called, which can take a lot of time on the server side to get the results. So what is the best solution to cancel those calls when the user runs quickly through the list or just wants to cancel the call. Currently I'm just blocking the UI, so th user is restricted to wait.

On the client side I thought to pass a request id through the user state and just process the last call when it comes back. Like this:

[code language="csharp"]

private Guid _lastRequestId; private OnItemSelected(int itemId ) { _lastRequestId = Guid.New(); _proxy.DoSomething(itemId, _lastRequest); } private void _proxy_DoSomethingCompleted(object sender, DoSomethingCompletede) { Guid requestId = (Guid)e.UserState; if(_lastRequestId==requestId) { ProcessAndDisplay(e.Result); } }

[/code]

At least I would save the compute time on the client side and prevent the dispaly of wrong data. But than flicking through the item list would be like a DoS attack.

Any ideas how to solve those problems?

Having difficulty RDC into server from my work PC

RodAtWork — Wed, 11 Nov 2009 21:34:03 GMT

I'm working at home today, using Microsoft's Mesh (www.mesh.com) to connect to my work desktop PC. (It is running Windows XP SP3. At home I'm using Windows 7.) This is working very well, and I'm thankful!

However, there is one sticky point. I want to be able to remote desktop connect from my work PC to one of the servers on our network. I have tried, repeatedly, to RDC into various servers, but have failed each time. I'm always getting the error message:

The system could not log you in. Maka sure the username and password are correct and try again.

I have made sure that the usernname and password are correct. I have tried multiple accounts on 4 different servers, and I'm getting the same error messages for all attempts. What could be causing this problem?

[Side-]Effects

Bent Rasmussen — Wed, 11 Nov 2009 19:46:14 GMT

I thought it would be interesting to gather a collection of more or less strange effects, sort of an effect zoo. Effects can be harmful to program reasoning in many ways but they can also be fun.

asd

adhamit — Wed, 11 Nov 2009 12:54:57 GMT

asdasd

How to read ERRORLEVEL in vbscript-Really need help

adhamit — Wed, 11 Nov 2009 12:52:45 GMT

Hi all experts out there,

Actually, i am developing a script to decrypt files (using .bat).

Since require us to loop into the folder(to read fodler name), i have created a short vbscript as below

------------------------------------------------------------------------------------------------------------------

Dim strSubFolder
Dim strFile
Dim strOrganization
Dim strRootDir
Dim strSubFolder2
dim shell
set shell=createobject("wscript.shell")
strOrganization = "Org1"
strRootDir = "D:\GFTPRoot\AG\" & Trim(strOrganization)
Set objFSO = CreateObject("Scripting.FileSystemObject")
Set objFolder = objFSO.GetFolder( strRootDir )
Set colSubfolders = objFolder.Subfolders
For Each objSubfolder in colSubfolders
strSubFolder2=objSubfolder.Path & "\FileIn"   'only browse thru FileIn folder
If objFSO.FolderExists( strSubFolder2 ) Then
   Set objFolder2 = objFSO.GetFolder( strSubFolder2 )
   Set colFiles = objFolder2.Files
   For Each objFile in colFiles
     If UCase(objFSO.GetExtensionName(objFile)) = "GPG" Then


shell.run "AG_Decrypt_Backup.bat"

----------------------------I NEED TO RETURN THE %ERRORLEVEL% HERE---------------------------------------

End If
Next
End If
Next
set shell=nothing
Set objFile = Nothing
Set colFiles = Nothing
Set objFolder2 = Nothing
Set objSubfolder = Nothing
Set colSubfolders = Nothing
Set objFolder = Nothing
Set objFSO = Nothing
Wscript.Echo "Completed"

-------------------------------------------------------------------------------------------------------------------

As you can see, the vbscript will call AG_Decrypt_Backup.bat.

In my batch file, i have specify to return the ERRORLEVEL

In vbscript, noticed that we need to specify the errorlevel by using

WScript.Quit(3)

Since in vbscript we loop for each of the files, it might have different errorlevel.

how do i can retrieve the errorlevel from my batch???

So that i can display in my vbscript?

p/s: my batch file use to decrypt file with .GPG extension

Thanks & Best Regards,

How to rip DVD on Mac?

laaa — Wed, 11 Nov 2009 05:44:48 GMT

Recently, I have a Wondershare DVD Ripper for Mac, but do not know how to use it, who could help me?

Data grid and server-driven paging

Chl9 — Tue, 10 Nov 2009 13:56:26 GMT

I've seen a Silverlight 2 Beta 1 demo (http://blogs.msdn.com/swiss_dpe_team/archive/2008/03/17/silverlight-2-beta1-wcf-linq-to-sql-a-powerfull-combination.aspx) which shows 'paging' in a data grid.

It uses an asynchronous service callback which sets the ItemsSource of the data grid and the Maximum of the scrollbar.

void GetDataCompleted(object sender, GetDataCompletedEventArgs e) {

    dataGrid.ItemsSource = e.Result;
    myScrollBar.Maximum = e.count;
    ...

Will that also work with the new .Net 4 WPF data grid?

I've tried to do that with .Net 3.5 WPF data grid but without success.

In other words will the new .Net WPF data grid (not Silverlight!) have support for paging?

Regards,
Oliver

Helooo.....

vyke.asp.net — Tue, 10 Nov 2009 12:36:48 GMT

Does anyone respond to any posts on these sites???

Monads

Richard.Hein — Mon, 09 Nov 2009 21:03:47 GMT

I have a question about monads ... if they are really the "fundamental unit of composibility" as put forward in a few of the Channel9 interviews with Brian Beckman and Eric Meijer, then isn't it practical to assume that the goal should then be to ensure that everything is in a monad? Does that actually make sense, and is it even possible?

Access to SharePoint Lists from C#

PerfectPhase — Mon, 09 Nov 2009 18:30:10 GMT

I have a service running on a server in my domain that needs to be able to read and update data in a sharepoint list. This is a simple list with numeric and text fields only.

Was wondering what the easiest/best way of getting access to the data is?

Cheers,

Stephen.