Advogato blog for Chicago

16 Jul 2008

Wed, 16 Jul 2008 21:55:17 GMT

Work Demonstration Complete

My Arduino board was being used for a demonstration at work, but it enabled me to get a lot of use out of it and work bought me a couple of bits that I wanted to play with, notably a network interface and a Mifare reader module.

Anyways, its back to being used for what I want to do things with, notably robot building. However, this time I am being distracted by a different use, which is sound generation - or should I say Noise generation.

I have had my imagination sparked by the prospect of using the Arduino plus some knowledge I have gained from my ham stuff to generate a synth. It's been done before, but not by a lot of people.

There seem to be a couple of routes to go down - This page documents the different ones. The main ones seem to be this:

Use the Arduino to control a synth or other noise making source.
Use the Arduino *as* the synth.

I've not yet completly decided which route I'm going down, I know that the sounds generated by the first method might be... better, but I have an aweful lot to learn about generating noises...

15 Jul 2008

Tue, 15 Jul 2008 22:02:51 GMT

More posts about things which are not-quite-work
Its increasingly difficult to talk about things which are work related because, well, I'm not allowed to. Because the work is what I'm interested in and takes up so much of my time, it does mean that some blogs being to dry out.

Arduino java.lang.StackOverflowError
It seems obvious if you know, but there isn't that much in the Google results for a search with those keywords. Basically, this happens if you do something silly with strings and quote marks... for example, compiling the following (in Arduino 0011):

Serial.print("rar);

Ok, now, its not immediately obvious without good syntax highlighting that the " is missing from this, and compiling won't give you a line number where it all goes wrong.

I Think The Stack Overflow Error is caused when the distance between this typo and the next " is so big that it would cause a StackOverflow... I think. Im now not sure. Eitherway, look for missing quotemarks or similar typo's.

15 Apr 2008

Tue, 15 Apr 2008 16:40:16 GMT

Visual Studio, HttpModules and compiling for IIS6

Things are becoming a little tricky. Because Windows 2008 has only just been released, the migration to that is going to be relatively slow (I can't realistically suggest that we have our production server as a 2008 box ... yet). So we're stuck with using Windows 2003 and IIS6 for our .Net hosting.

However, we're programming on Vista boxes, which of course, are running IIS7 and all its finery. Now, having a test platform which is a different version to the deployment platform is never a good idea, and right now, its a royal pain in the ass. And why? Well, randomly, the way I add headers:

Good

response.AddHeader("Content-type", "text/html");

Bad

response.Headers.Add("Content-type", "text/html");

The first one works, the second one ...

System.PlatformNotSupportedException: This operation requires IIS integrated pipeline mode. at System.Web.HttpResponse.get_Headers() at ...

Go figure.

6 Apr 2008

Sun, 6 Apr 2008 21:54:38 GMT

MS SSMSE 2005 Error on Installation on Vista

Ok, if you're an indie developer for the Microsoft platform, then you might have SQL Server (Express) then you might also want to install MS SSMSE (Microsoft Sql - Server Management Studio Express).

The Good

Ok, so you've downloaded the SSMSE install package, and it doesn't install and the MS reference for it is about permissions on the Data Directory. There might be one single file which has the wrong permissions, but I couldn't find one. Installations continue to fail no matter what the install user is.

The Ugly

To install, there is a very simple solution - Turn UAC off - its in the user panel of the control panel. Then installing SSMSE is painless. Just remember to turn UAC back on again after you've done it, oh and pray that you dont need UAC's protection for the few minutes that you had it turned off... (Why do you think this section is entitled "The Ugly"?)

The down-right-Bad

If you decided to go with MS Sql Server 2008 Express because, well, why not... (think of all those new features) then you have a bigger problem. At the moment, SSMSE is only available in the 2005 variant, which does not allow connections to a 2008 Express service.

3 Mar 2008

Mon, 3 Mar 2008 14:13:55 GMT

A good workman never blames his tools

This weekend for me has been a near disaster. I started work on my SpokePov and USBTinyISP. Then my Solder Iron melted. Not the plastic hand wrap, no, the nib. Thats it for soldering - no more soldering being done without a soldering iron.

I now need to go and buy a nice soldering iron which is temperature controlled - if you use one thats too hot, you end up having problems, if you use one thats too cold or does daft things (like the cold solder one) then you have problems.

So now I have a fully built USB dongle, and a half-built SpokePov, and a not very happy monster.

18 Feb 2008

Mon, 18 Feb 2008 16:46:15 GMT

IIS 6, 64 Bit Windows and No ASP.NET tab!

Ok, this one had me stumped for a bit, and it took me a long time to find out why. Basically, the problem is that there is no ASP.NET tab in website properties, and this is because .NET isn't installed properly. The first thing to do is download and install .Net framework, which dosn't seem to do anything.

The second thing to then do is to run: %SYSTEMROOT%\MICROSOFT.NET\Framework64\v2.??\aspnet_iisreg -i which will then try and re-register. Now if this "works" but dosnt have any effect, its probably because you've got a beta of .Net installed. However, if this throws an error, its probably because IIS is running in 32bit mode.

Why would it be? Well aparantly it has to to be able to deal with PHP. Maybe thats true, maybe it isn't any more - but either way, theres lots of install guides out there telling you how to break it into 32 bit mode. To Fix...

cscript %SystemDrive%\inetpub\AdminScripts\adsutil.vbs set w3svc/AppPools/Enable32bitAppOnWin64 0

The 0 is what sets it back to default (64 bit) where having that as a 1 will set it to being 32 bit mode. Of course now all your PHP is probably broken. But then again it was anyways.

Just re-run the first command, and reboot (IIS? Server?)

9 Feb 2008

Sat, 9 Feb 2008 16:36:02 GMT

.Net Interop

This post should really be titled "Please write 1000 times, Vista is Not XP". Yesterday, I had the pleasure of having to look at how to write .Net wrappers around a Windows dll - to be precise, the Smart Card interface - WinSCard.dll. We've previously written code in C, but really the time is to move on and use C#. The problem's been addressed before, and it dosn't take a genius to find Google has references to Smart Cards in .NET. In particular, this is the second part of a three part essay. The first part discusses using a COM object to wrap around the dll functions, but this is the simpler way of doing it.

Apart from the required usinglines, the code to do this, is relativly simple:

public class MyClass{
  [DllImport("WinScard.dll")]
  public static extern int SCardEstablishContext(
    uint dwScope,
    int nNotUsed1,
    int nNotUsed2,
    ref int phContext);
}

This is a fully functioning class which provides the interface to one of the functions in the DLL. Now, whats the problem?

Well, in this instance, its a security violation. Some of the dll functions can be called and run without any problems at all, but some of them cause AccessViolationException. The helpful hint that comes with it suggests that this is because memory is corrupt (and after lots of uhming and ahhing we decide its not). No, the problem is because the memory is protected. In Vista that is. The same code running on XP provides no problems whatsoever.

Now heres my problem - my Google skills, usually pretty nifty, are failing me - I am struggling to search the great intertubes for a solution I am still scratching my head. The combinations of keywords I'm using still only come back with results are either:

1) Useless 2) People suffering the problem who havn't solved it. 3) Results about something similar in XP which has the same exception which is fixed by a MS .Net hotfix (which is irrelevant). 4) People who have a solution along the lines of "run your code as root".

So I need to spend more time looking at that soon.

7 Feb 2008

Thu, 7 Feb 2008 17:15:50 GMT

Build Tools

Ok I'm pretty on top of the world at the moment, mostly because I've spent two days in "the Zone", and in that time I've managed to write some very handy new tools for the new project, mainly: The new improved build procedure is now in place, and its using a streamlined batch file to build it. It basically uses a program that I've written (CompilerWriter) that is called both Before and After the compilation - using arguments Pre and Post.

It also uses Cloc as an alternative to Sloccount (Cloc is much faster in a Windows Environment, not to mention running nativly without having to mess around with Cygwin).

Call Pre-compiler to make entries into Database and generate the unique id for the build. Write the assembly info.cs file and return the id of the database entry.
Call the compiler and capture the return code. Send all errors, warnings and notices to a file.
Call the code line counter and put its output into a file (CSV)
Call the post-compiler giving it the return information from the compiler, along with the error file, and the code line counter. It then moves the build to the test folder, corrects the databse entry line for its counts of error and file size, and also moves it into the historic build folder along with copies of all the reports

All together, its working very nicely - it generates a HTML report of the build and opens it in a tab in Firefox. Now, I could combine these tools in an ANT or a MSBuild file, but instead I just made a batch file to do it all.

4 Feb 2008

Mon, 4 Feb 2008 17:56:03 GMT

MSSQL

Oh that wonderful height of confusing riddles. Some interesting things that I've noted (and mentioned before no doubt) that in the connection string, the use of Localhost actually causes a network / tcp connection. It seems that the way to force a local area connection (Shared Memory or Named Pipe) is to use (Local) or .. However, if you're connecting to an SQL Express install (and what ms "indie" developer isn't) then you need to use something along the lines of data source=.\SQLEXPRESS in your connection string.

Also note that some confusing errors might occur if you don't - "Failure to connect" is the main essence, but the message goes on (unhelpfully) to explain that this might be caused by a lack of allowance for a) named pipes or b) remote connections. How many hours have people spent scratching their heads going "But I've turned those on!".

In fact, you don't need to turn either on, just adding the \SQLEXPRESS should be all that you need to do.

Jmon / AngryBot

So, with Log4net now logging to the MS-SQL database, the framework for Jmon is now being built for the second time. My original framework (which the project name still is AngryBot) was quite good apart from it had too many hacks in it where I taught it how to play Poker (it required some not very nice hacks to listen to the poker bot and work out what hand it had. It also didn't have a very good idea of some of the specific differences in hands).

I know I haven't released the source code yet - I'm trying to tidy it all up, and the main reason is that I'm slightly embarrassed about a bit of it, and that bit is this - the main core, which I never got round to writing properly.

The IRC side uses SmartIrc4Net by Meebey, which deals with everything IRC related. I hook into the message received event, and deal with it basically like this:

if (e.Data.Message.StartsWith("!")) { string classname = "AngryBot.Commands." + tag.Substring(1).ToUpper(); ObjectHandle handle = Activator.CreateInstance(null, classname); BaseCommand command = (BaseCommand)handle.Unwrap(); command.Run(irc, e); }

But what if the command dosn't exist I hear you say - what if someone goes !Bang and the class AngryBot.Commands.BANG does not exist? What if it does exist, but isn't a BaseCommand? What happens when someone sends "!"? Well, around that is a try-catch which gets everything that breaks, and just ignores it.

I know. Eww. And that's why you haven't got the code released yet, because its just not worth it.

1 Feb 2008

Fri, 1 Feb 2008 15:24:10 GMT

In fact, my previous-to-previous post also contains more issues which I had not really looked into, partially because of unreliable information that sites had told me, and also partially because I forget that when you read Blog posts (even blog posts from the company who are producing the software), anything that speculates about the future is doing just that - speculating.

Windows 2008, being launched officially in some 26 days according to Microsoft is the reason that people don't have a migration path from Windows 2003 to Vista-servers. Blatantly because they will be migrating to Windows 2008.

Starting a project right now is really bad timing. We basically have no choice but to write it for Windows 2003 & IIS 6, because our deployment date will be before 2008 has passed our stringent "hmm well it hasn't fallen over *yet*" style credence plans. If only 2008 had been released in 2007...

surely it doesn't matter but it does. We don't make "websites". We're doing funky things with managed code and talking to hardware modules. We have a vision of what we want to write, we know how it breaks down in the project, and now, we have the leisure of being able to select our tools. And this selection process is killing my mind.