#region Coad's Code

My Blog Has Moved to blogs.msdn.com

2006-01-05T06:34:00Z

We'll, after being at MS for over a year now, with the encouragement of friends, I've made the move to blogs.msdn.com. My new blog site is:

Blog moved to:
http://coadblog.com

Which redirects to http://blogs.msdn.com/noahc. Please update your readers. Cheers!

VSTS MSDN Chat

2005-11-15T22:46:00Z

Team System MSDN Public Chat

Visual Studio Team Edition for Software Developer &
Visual Studio Team Edition for Software Testers

When: Wednesday, November 16th @ 10am PST
What: Join us to discuss the Profiler, Test Tools (Unit, Generic, Manual), Web & Load Testing, and Code Analysis (FxCop & PREFast). We have questions for you, will answer questions from you, and will chat about the exciting new technology.
Where:http://msdn.microsoft.com/chats

VS05 Express Free for a Limited Time

2005-11-07T17:37:00Z

Visual Studio 2005 Express editions (WebDev, C#, VB, C++, J#) are officially Free! for 1 year (expires 11/6/2006).

I just watched Steve Balmer give the keynote at the first and official kickoff launch event and he talked about the great Web Developer Starter Kits w/ a demo that was real cool. Want to start up a website fast? This is the way to get started and experience the awesome power of ASP.NET 2.0!

Please be sure to register your free download so we know how popular these are. My guess is that the more people we have register, the better the chance these will be free (or as inexpensive as possible) longer.

Visual Studio 2005 Launched

2005-11-07T17:18:00Z

As of today, Visual Studio 2005 has officially launched! This is a fantastic product that we have all been long awaiting!

There are a number of launch events being held in cities around the world the next month. Check out if one is in your city soon. I'll be at the Dallas Launch on November 30th. If you're going to be there, `let me know`|`mailto:noah@coad.net?subject=Dallas Launch Event`.

MSDN Subscribers can download Virtual Server/PC images with Team Suite installed for evaluation. This gets you up and running quickly on Team System without having to worry about installing Team Foundation Server. There are a number of other ways you can Evaluation Visual Studio.

New! Team System MVPs

2005-10-11T03:02:00Z

We have new Visual Studio Team System MVPs!

An MVP competency for Team System was just created. You can see the full list of our new Team System MVPs on the Microsoft MVP Site or read what an MVP is.

We have 9 Team System MVPs who are truly rock stars in the community. It is exciting to have such stellar people as our MVPs! Welcome to the team ... Team System MVPs!

Here are some of their blogs (in no particular order):

Rick LaPlante (General Manager, top VSTS dude) with some of the Team System MVPs
From left to right: Guy Barrette (an ASP.NET MVP), Chris Menegay, Rick LaPlante, Jean-Luc David, David McKinstry, Etienne Tremblay

Wedding & Honeymoon Photos

2005-07-26T05:50:00Z

They're here! The much requested photos from our Texas Wedding & Maui Honeymoon. Just click the links to see the full online photo album. Here are two sneak preview pics.

Just married!

Enjoing Maui to the fullest!

I'm giving this MSN Spaces thing a try since it was quick and easy to create the online photo album. When I get my new website up and running, I'll be able to add a lot more photos.

Previous wedding related blog posts:
Getting Married Today!, Countdown to My Wedding, 14 Days to I Do & Engaged to an Angel

New Living Room w Couches

2005-07-15T19:02:00Z

For the last several years, I've dreamt of having a real leather couch! My living room at my Redmond (Seattle) apartment has been completely bare since I moved in (a year ago) with the occasional influx of moving boxes (from when I moved in then Dawn moved up). Occasionally I'd just sit on the floor in the middle of the completely bare living room dreaming of the day I'd be able to come home to a comfy couch, have guests over, and making it feel like a real home.

Now that I'm married (to the wonderful Dawn Coad) I'm out of the college / bachelor scene (Ikea like furniture) and have entered the realm of 'real' furniture. Dawn and my first big purchase as a married couple, one month after getting married, was a couch, love seat, chair, ottoman, coffee table, and end table from Mor Furniture.

We've waited a long six weeks for delivery and as of last night, it all arrived! It is very exciting! What am I doing this weekend? Hanging out in my living room!

Before - Just an empty living room for the last year.
Imagine me just sitting here on the floor Indian style, yup, sad.

After - A whole new experience! Now it actually looks like a home,
a place to hang and invite friends over.

For those of you that blog, have you noticed how much easier and faster it is to get a blog post out when you're excited about a new thing? That's what this is, I'm excited, here working at Microsoft on a Friday wishing I was hanging out on my couches, so what do I do? Blog about them!

C# Resources

2005-05-20T19:24:00Z

Introduction

Here is my base collection of resources on C#. I'm putting this together so when I write articles or reply to e-mails, I have one central place to point people. This is a live post, which means I'll be updating it as needed. Feel free to make your own additions (in the feedback)!

Get C#

Visual Studio 2005 C# Express
Currently free for the first year (till 11/06), then it will be $50. While not quite free (in the long term), it is a very moderate and reasonable price for the power you get.
Visual Web Developer 2005 Express
If your primary target is the web (with C# or any other .NET language), use this SKU. You can install both this and C# Express side-by-side. C# Express is geared toward Windows Application and this is for web sites, both support C#.
Visual Studio 2005
Again, currently free while in beta, and will be about $800/$560 when released.
MSDN Subscription
Various levels of access to all of Microsoft's operating systems and development tools for a year. MSDN Premium costs $1100 to $3200 per year and includes one of the Visual Studio 2005 Team System editions.

Learning C#

So you're starting out and would like my secret to success in C#? You've come to the right place! With you're passion, this is a sure-fire way to success in .NET:

Get C#
You can start with the free C# Express (for Windows Applications) or Web Dev Express (for Web Sites, Web Services, etc). Both contain the C# language. These contain great resources when you start them up on learning the language. Go through the tutorials and resources they present on the start screen.
Study Books
Particularly the first two or three I list below. Dig into these. Everyone I know who has grasped this content has done well. They teach solid fundamentals, as well as practical application, from which all else stems.
Subscribe to Blogs
Start reading on a daily basis the blogs I list below and find others that tickle your fancy. Using an aggregate reader like RSS Bandit is practically a must. Consider starting your own blog where you can post tidbits you learn. Doesn't matter how newbie you may be, others will learn from you. Some of the simplest blog posts are the most useful.
Use Forums
Browse through issues other devs are encountering, ask you own questions, and look for questions that you may be able to answer. The more you do so, the better you'll be able to articulate what you're doing, understand it yourself, and learn to help other. This is how I obtained my MVP award.
Play Around
The #1 way to really learn is to get in there and do it. Try creating your own projects. Think of cool little things to make and just do it on your own time, a photo slide show, an MP3 tag editor, a way to track friend's birthdays, your own contact's list, a personal website, a database of scrapbooking supplies. Come up with an easy idea, make it, then make it better. A passion of getting in and doing it is the #1 anyone learns (myself included).

Armed with a passion to learn, just by following these 5 steps, you too will quickly become a C# developer.

Online Centers

MSDN
Microsoft Developer's Network. The #1 dev resource for anything Microsoft.
Visual C# Dev Center
The official C# home site.
.NET Class Library
The entire .NET framework class library reference.
.NET Framework Developer Center
Microsoft's official development center for everything .NET.
.NET Rocks! Internet Audio Talk Show
This is the greatest online weekly talk show where everything .NET is discussed.

Sample Code & Tools

Shared Source CLI
This is the entire ECMA standard Common Language Infrastructure in C# source code. These are all the Base Class Libraries (BCL) that make up .NET in plain code. See how System, string, XmlDocument, etc is implemented. Extremely valuable educational resource!
C# Team Downloads
Many .NET code samples, tools, powertoys, etc from the C# team.
.NET Downloads
SDKs, Tools, Utilities, Sample Code all on .NET from MS

Books & Periodicals

Book: Visual C# .NET Step by Step
A great place to start learning C# for both Windows and Web Apps. This is my first recommendation to new programmers.
Book: Inside C#
Quicker paced and more indepth, this book describes the insides of the language and class libarary more. Another must have.
Book: Visual C# .NET (Core Reference)
Various topics in C#, a great book once you understand the basics.
Book: A Programmer's Introduction to C# (Second Edition)
Written by Eric Gunnerson, a developer on the C# team.
Magazine: MSDN Magazine
The best periodical on .NET technologies. $35/year to subscribe to in the US.

Blogs
Subscribe to these blogs using RSS Bandit (download) (open source in C#).

C# Team FAQ
The official C# team spoutlet. Once can learn a lot of interesting things here.
C# on #region Coad's Code
C# posts on my blog.
Cyrus' Blather
Cyrus is a very vocal dev on the C# team and has some of the most lively C# discussions online.
Eric Gunnerson's C# Compendium
Eric is a developer on the C# team and one of the most knowledgeable people in the world on C#.
jaybaz [MS] WebLog
Jay is a lead developer on the C# team, and another of the most all knowing C# dudes.

Forums, Newsgroups, and Usergroups
These are some of the best places to go for help.

C# Forums
Microsoft's official support outlet for C# developers. These forums will eventually replace the newsgroups all together.
C# Newsgroup
This is the old C# support newsgroup that will be replaced by the C# forum (above).
.NET Usersgroups
Find a local .NET support group in your area. They tyically consist of like minded developers, presentations, meetings, prizes, special events, and are a great way to meet other .NET developers face to face.
GotDotNet
A community run .NET site sponsored by Microsoft.

Support, Getting Help

#1 place to go, the C# Forums.

Domain Specific Resources
Coming when I have the time to add them.

Team System
ASP.NET
General Web Development
ADO.NET
XML
SQL
Windows Forms
Serial & USB Communications

Getting Married Today!

2005-04-30T15:32:00Z

In just three hours I'll be waiting for my beautiful blushing bride at the alter!!

I'm in the hotel with my Best Man with half a tux on getting ready to head over to the church. Friends and family are pouring in from around Texas and even the nation for this special occasion. I can hardly wait!

At 3am my Best Man and I dropped off a "Happy 0th Anniversary" card and long stem rose in front of Dawn's parent's house for her to find this morning. That's it, I'm trademarking the "0th Anniversary" theme, very appropriate since the start of arrays is usually a 0 index (defiantly in C#), and this is the start of our new life together.

Other "Getting Married" Posts:
Countdown to My Wedding, 14 Days to I Do & Engaged to an Angel

Countdown to My Wedding

2005-04-24T09:40:00Z

My wedding is rapidly approaching! Here is how much time is left until my wedding on Saturday April 30th 2005 @ 1:30 PM CST. If it is after that date, the time is counting how long I've been married.

Here are two other posts about my upcoming wedding.
14 Days to I Do & Engaged to an Angel

Note: RSS Bandit, other RSS feed viewers, and some browsers will not display the timer. Please view this blog post in IE for best results.

New MSDN Forums Replace Newsgroups

2005-04-23T00:57:00Z

MSDN has moved to using cool new web forums to replace the old Whidbey newsgroups. The new forums have tons of features! There are RSS feeds, alerts, a nice UI, easier moderation, and much more.

One good feature is that we on the product team recieve daily e-mails of unanswered questions. This means a quick response to your posts.

Please give them a try. What do you think?

Visual Studio 2005 (Whidbey) Beta2 is Here!

2005-04-19T01:16:00Z

Whidbey Beta2 is Released! We all (you & MS) have been waiting long for this build! Wow, it is a substantial improvement over Beta1 and the client bits even have a Go Live License. I'm excited! How about you?

If you have a MSDN Subscription, you can Get the Beta for the cost of S/H or download Visual Studio 2005 - Team System (aka VSTS). There is a Go-Live License which permits "production deployments of customer applications".

For the free (for now) Express SKUs: C#, VB, VC++, J#, Web Dev, SQL Srv

14 Days to I Do

2005-04-17T02:21:00Z

In just two weeks from today, I'll be waiting at the alter for my fiance to walk down the isle to receive her hand in marriage. I'm very excited!

Dawn is aggresively packing up her appartment in Bryan, TX to be moved out by next week. Next week is also her last week teaching orchestra for two middle schools in Bryan ISD. We are both working fast & furious on finishing up wedding details.

The wedding is Saturday, April 30th in Houston, Texas @ Lakewood United Methodist Church, our reception is being hosted at Raveneaux Country Club, and we are headed to Maui, Hawaii for our honeymoon. We both have large families so it is going to be a big event!

We have a Wedding Site and here is my post about getting Engaged to an Angel.

Our 'official' engagement photo (from a scanned proof).

Dawn recieves her engagement ring at Chritopher's World Grill (August 2004).

On the Victoria Clipper on our way to Victoria B.C. Canada.
We had a wonderful time in beautiful Victoria!

Favorite Web Design Links

2005-04-10T04:43:00Z

These are some of my core reference links that I consistently refer back to while working on the web (mostly from MSDN). I also use them with many other projects, but most frequently with web/html/scripting/xml apps. The main links have been listed on my IE Links toolbar for awhile and now I can replace them all with a single link here.

I'll be updating this as I come across more. If you have any recommendations of reference links you use frequently, please leave a comment and I'll add them.

Main References
CSS, Color, DHTML, HTA, Regex, JScript, WSH, Filters, Script Runtime, SQL

eXtensible Markup Language
XML, XSLT, XPath, DOM, Node, DHTML, XmlNode, XNode

Secondary Links

SerialPort (RS-232 Serial COM Port) in C# .NET

2005-03-24T02:28:00Z

This article is about communicating through the PC's Serial COM RS-232 port using Microsoft .NET 2.0 or later by using the System.IO.Ports.SerialPort class.

Way in the Past...

Back in my early (pre C# MVP) days, I had written an article on DevHood titled Serial COM Simply in C#. It became quite popular and is (currently) the top Google search for "serial c#". Now every week I get several e-mails with people asking questions and it is high time for some serious updating.

The article was (originally) written soon after .NET was introduced to the world, and other .NET serial port controls had not yet been written. So at the time, this was an easy solution. Just use the MSComm.ocx control from VS6 which most Devs had at the time. Now however, there are many easier and preferred methods than dealing with the complexities of interoping with an old legacy (non-.NET) ActiveX OCX control.

A Bright Future is Here!

Today, the primary solution is to use the new SerialPort control that is part of .NET 2.0 and is freely available in C# Express on MSDN. It is considerably easier to use and is a true .NET component.

For loyal fans of the tutorial, I've written a sample code application, SerialPortTerminal.zip, which you can try out to see how the new SerialPort control is used. Requires Visual Studio 2005 & .NET 2.0 or later to compile & run.

Continued Support

Due to the high volume of e-mail I've been receiving on serial port communication in general, I've wrote this post and added an FAQ section to the bottom of the post. Check this first if you have questions. If you post a question as a comment that hasn't been answered in the post, I'll add it to the FAQ section.

For those of you who I've directed to this blog post, please understand that I'm just another guy working away at a full time job (helping manage the release of Team System) who has worked with serial RS-232 ports in the past (moving on to USB now). I like to help people, hence I wrote the original article, this sample code, and the FAQ, but do not have the resources to answer additional serial port communication questions. Please check out the SerialCom FAQ for other .NET COM Port solutions and technical support options.

Get Connected Up

You can obtain USB to Serial adapters (from NewEgg, search using Froogle) and have just about as many ports on your PC as you like. I carry around two adapters with a null modem (what is it?, search Froogle) between them so I can create a loopback to send & receive through to separate ports on most any computer. I'd recommend doing the same for when writing code for the serial port.

If you'd like to quickly and easily create your own external devices to communicate with the PC, I recommend starting with the Parallax BASIC Stamp modules. Parallax has lots of easy accessories (such as LCDs, RF, Sounds, AD & DA, etc) for their modules. After that you could migrate to an Atmel Microcontroller (recommended) or Microchip PIC.

Let's Have the Code

Here is an example of how easy it is to use the new SerialPort control.

Very simply, here is how you can send a bit of data out the port.

// This is a new namespace in .NET 2.0
// that contains the SerialPort class
using System.IO.Ports;

private static void SendSampleData()
{
  // Instantiate the communications
  // port with some basic settings
  SerialPort port = new SerialPort(
    "COM1", 9600, Parity.None, 8, StopBits.One);
  
  // Open the port for communications
  port.Open();
  
  // Write a string
  port.Write("Hello World");
  
  // Write a set of bytes
  port.Write(new byte[] {0x0A, 0xE2, 0xFF}, 0, 3);
  
  // Close the port
  port.Close();
}

Now let's take a look at what it takes to read data in from the communications port. This demonstrates reading text; for an example of reading binary data, see my SerialPortTerminal.zip sample app.

Create a new "Console Application" and replace all the default class code with this code
Add a reference to "System.Windows.Forms" to the project
Run w/ F5, to exit the app, press Ctrl-Break.
Get Connected Up with two USB to Serial adapters and a null modem
Use another app, the code above, or the SerialPortTerminal.zip example to send data and watch it come in with this code

#region Namespace Inclusions
using System;
using System.IO.Ports;
using System.Windows.Forms;
#endregion

namespace SerialPortExample
{
  class SerialPortProgram
  {
    // Create the serial port with basic settings
    private SerialPort port = new SerialPort("COM1",
      9600, Parity.None, 8, StopBits.One);

    [STAThread]
    static void Main(string[] args)
    { 
      // Instatiate this class
      new SerialPortProgram();
    }

    private SerialPortProgram()
    {
      Console.WriteLine("Incoming Data:");

      // Attach a method to be called when there
      // is data waiting in the port's buffer
      port.DataReceived += new 
        SerialDataReceivedEventHandler(port_DataReceived);

      // Begin communications
      port.Open();
      
      // Enter an application loop to keep this thread alive
      Application.Run();
    }

    private void port_DataReceived(object sender,
      SerialDataReceivedEventArgs e)
    {
      // Show all the incoming data in the port's buffer
      Console.WriteLine(port.ReadExisting());
    }
  }
}

One of the (several) new methods that is supported, and one I'm very glad is finally here, is the ability to obtain a list of the COM ports installed on the computer (ex: COM1, COM2, COM4). This is definately helpful when you want to present the list of ports avalible for the user to select from (as in the SerialPortTerminal.zip Win App example).

foreach (string s in SerialPort.GetPortNames())
  System.Diagnostics.Trace.WriteLine(s);

Here are two helpful little methods for sending files through the serial port. Of course, these are the bare essentials and as always, you should check to make sure the port is open first (port.IsOpen) and use try/catch around trying to open a file, but you get the gist with this code. The binary sending routine is limited to about 2GB (the size of an int), but this should be okay for most uses.

using System.IO;

private static void SendTextFile(
  SerialPort port, string FileName)
{ port.Write(File.OpenText(FileName).ReadToEnd()); }

private static void SendBinaryFile(
  SerialPort port, string FileName)
{
  using (FileStream fs = File.OpenRead(FileName))
    port.Write((new BinaryReader(fs)).ReadBytes(
      (int)fs.Length), 0, (int)fs.Length);
}

RS-232 Project Photos

Each of these involve RS-232 serial port communications.

Just what's needed to get started with microcontrollers,
a Basic Stamp, mini LCD display, power, and RS-232 port.

Two USB to Serial adapters with a null modem
to loopback and test your serial software.

The brains to a mini automated radio station that let me
control my PC & home using my HAM radio from around town.

Port Wiring Notes

DB9 Male (Pin Side)                   DB9 Female (Pin Side)
DB9 Female (Solder Side)              DB9 Male (Solder Side)
    -------------                          -------------
    \ 1 2 3 4 5 /                          \ 5 4 3 2 1 /
     \ 6 7 8 9 /                            \ 9 8 7 6 /
      ---------                              ---------

DB9 Female to DB9 Female Null-Modem Wiring
 2 |  3 |  7 |  8 | 6&1|  5 |  4
---- ---- ---- ---- ---- ---- ---- 
 3 |  2 |  8 |  7 |  4 |  5 | 6&1

9-pin   25-pin  Assignment                 From PC
------  ------  -------------------------  ------------
Sheild  1       Case Ground                Gnd
1       8       DCD (Data Carrier Detect)  Input
2       3       RX  (Receive Data)         Input
3       2       TX  (Transmit Data)        Output
4       20      DTR (Data Terminal Ready)  Output
5       7       GND (Signal Ground)        Gnd
6       6       DSR (Data Set Ready)       Input
7       4       RTS (Request To Send)      Output
8       5       CTS (Clear To Send)        Input
9       22      RI  (Ring Indicator)       Input

- RTS & DTR are binary outputs that can be manually set and held
- DCD, DSR, CTS, and RI are binary inputs that can be read
- RX & TX can not be set manually and are controlled by the UART
- maximum voltages are between -15 volts and +15 volts
- binary outputs are between +5 to +15 volts and -5 to -15 volts
- binary inputs are between +3 to +15 volts and -3 to -15 volts
- input voltages between -3 to +3 are undefined while output voltages
  between -5 and +5 are undefined
- positive voltages indicate ON or SPACE, negative voltages indicate
  OFF or MARK

Other Resources

Here are some additional sites, libraries, tutorials, etc. These are links that I just found around the net and am providing for convenience (they are not endorsed).

Where CF = Compact Framework

The Final Say (aka Conclusion)

The new SerialPort class in .NET 2.0 rocks! It is much easier to use than getting the old MSComm.ocx control going in a .NET app, contains new functionality, is a 'native' .NET control, has docs built into the MSDN Library, and is easy to use.

Frequently Asked Questions (FAQ)

I'm adding this section (as of 8/10/06) to address the common questions I get on this post and through e-mail. Chances are, if you ask a good question in the comments here, I'll post it here for others to see easily.

Q: When updating a control (like a text box) while in the DataRecieved event, I get an error.
A: The SerialPort class raises events on a separate thread than the main form was create on. Windows Forms controls must be modified only on their original thread. Thankfully there is an easy way to do this. Each Windows control has a "Invoke" method which will run code on the control's original thread. So to put the recently received data into a text box (txtLog), this would do it: txtLog.Invoke(new EventHandler(delegate { txtLog.Text += comport.ReadExisting(); }); You can see this more in action in the "Log" event of "Terminal.cs" my sample code project, SerialPortTerminal.zip.
Q: I can't find the System.IO.Ports namespace.
A: Using Visual Studio 2003? The new namespace, and SerialPort class, is part of .NET 2.0 and Visual Studio 2005. It is not included in .NET 1.x (and Visual Studio 2003). Even if you have .NET 2.0 or Visual Studio 2005 installed, you can not access the class from within Visual Studio 2003.
Q: I only have .NET 1.1, what can I do?
A: Upgrade to .NET 2.0. Seriously, it's free. In fact, you can get the great C# and VB Visual Studio Interactive Development Environment (IDE) editors for FREE now with C# Express and VB Express. The .NET 2.0 Software Development Kit (SDK) for command-line development is also free. If you really must stay in .NET 1.1, you can use the technique I talk about in Serial COM Simply in C# or a 3rd party library.
Q: I'm sending data to my device, but it is not responding.
A: First make sure the device will respond using a standard app like Hyperterminal. Check the settings (baud rate, data bits, stop bits, etc) and make sure they match with your code. Try sending binary data via binary arrays. Many devices expect a carriage return at the end of a command, so be sure to send 0x0D or \n. String data can be easily converted to a binary array using:
byte[] data = System.Text.ASCIIEncoding.Default.GetBytes("Hello World\n");
com.Write(data, 0, data.Length);
Many devices require several carriage returns first to sync baud rates, so send several, like: com.Output("".PadLeft(9, '\n')); It you're communicating with a modem, make sure Echo Back is turned on. Send "ATE1\n". Other than this, just keep trying and playing around with it. It can be hard because you don't see the response from the device as easily as you would with a terminal app.
Q: When I put received data to a text box or rich text box, I get a strange symbols.
A: The default font of text boxes is designed only to show standard characters. Try using "CharMap" (a free tool in WinXP, click "Start", "Run", type "CharMap", enter). "Terminal" is a font designed to show classic ASCII characters and is what most terminal apps (like my sample code and Hyperterminal) use. There are also many ASCII codes that won't display correctly. This is why I choose to show the hex data instead of an ASCII string a lot of the time. System.Convert.ToString(mybyte, 16) will convert a byte to a string hex code, for example: byte b = 13; string s = Convert.ToStrong(b, 16).PadLeft(2, '0'), then s will contain "0D". See the "ByteArrayToHexString" and "HexStringToByteArray" methods in my sample app, SerialPortTerminal.zip.
Q: What about USB communications? How can I do USB?
This post isn't about USB. Believe me, I wish the .NET framework supported USB natively, and I'm doing what I can here at Microsoft to see USB get into the framework in the future. For now, you can use a USB to Serial adapter. I use a lot of these. They plug into the USB port, then appear just as a SerialPort to the PC. Microcontroller vendors such as Microchip, Atmel, and TI make chips that do this for projects. There is a lot of info on USB and C# out there too (such as this great article).
Q: Can I use the sample code here in my own projects (commercial or not)?
Yes! All sample code on my blog is free public domain material. I'm not a legal guy so I don't know the exact words to use, but I'll try... I'm not responsible for any problems! Use at your own rick etc. However, have at it, if it helps you out, fantastic, that's what it's here for.
Q: When using SerialPort.Open() (or SerialPort.PortOpen = true) I get the exception "UnauthorizedAccessException" or the error "An unhandled exception of type 'System.Runtime.InteropServices.COMException' occurred in axinterop.mscommlib.dll"
It may be one of a few factors:
- It may require Administrative privileges to use the port.
- The port may already be open by another program, only one app can use a port at a time.
- The port may not exist on the computer (this happens a lot). Verify the port you're trying to open is listed in the Device Manager (FAQ #9).
- The name being provided is not exactly correct.
  Use the full name of the port when opening, like "COM1" (not "1")
Q: How do I know what COM ports are on my PC?
Use the Device Manager ("Start", "Run", "devmgmt.msc") and look for the "Ports" node (see below). If you don't see a Ports node, it's because there are no Serial or Parallel ports installed in the PC. You can also use System.IO.Ports.SerialPort.GetPortNames() to return the list of available ports. Many laptops these day's don't have a serial port. You can get more serial ports very easily today with USB to Serial adapters.
Q: How do I communicate with my specific device? Modem, Mobile Phone, LED/LCD Display, Scanner, etc
This post is specific to general, device independent, serial port communications. You will need to find information about the protocol used for your specific device elsewhere. Comments that ask about specific devices will be deleted (to reduce spam). I'd recommend looking on the manufacture's website, writing/calling the manufacture, or searching online for your specific device, like "Motorola Razor Serial Protocol".
Q: What pins can I use for powering devices, a high signal, or for boolean input & output?
The TX & RX pins carry the standard serial signal, but the other pins can be used as high/low input/output pins. The output pins (4 DTR or 8 CTS), supply 5 to 15 volts (15v is proper RS-232 standard) when high and 0 to -15 volts when low. They only supply flea current so they're not meant to be used for powering any devices (like USB is designed for). However, they can be used as a reference voltage or for switching to one of the input pins for a high or low signal. The input pins (1 DCD, 6 DSR, 8 CTS, and 9 RI) can be used to detect a high or low signal. Proper RS-232 signal levels are -15v for a low and +15v for a high (compared to ground, pin 5). A MAX232 or similar chip takes a TTL 0-5v input and produces the -15v to +15v levels. However, most PC RS-232 COM ports will accept a 0v for low and 5v for high, but it is not guaranteed and alters from PC to PC. If you want a simple "toggle high", just hold pin 4 DTR high, and switch it to pin 1 DCD. The .NET SerialPort class has easy to use properties for switching the output pins high or low and for detecting the current level of the input pins. I have been able to use pin 4 DTR for a very low current (20ma max) PIC processors, but not reliably. I prefer to always supply external power and use pin 4 as a signal to turn on or off my device. I'll attach pin 4 to a transistor that switches my power source to my PIC to turn it on or off.
Q: What about ‘packets’? Does RS-232 support any commands or data segregation? OR Data comes in at seemingly random times?
Serial data flow through RS-232 has nothing to do with ‘packets’. It’s just a stream of bytes in and out. There is no guarantee that data arrives together.

Packet Protocols
Any notion of data compartmentalization (packets) would have to be coded by you for your unique use. Much of my time working with serial has been spent on defining useful packet like protocols, that usually include some type of header, command structure, and CRC check. For example, the first two bytes are the packet length, the next two bytes is the command, next two bytes are parameters, and the last byte is a CRC. Then my apps would buffer incoming data and look in the buffer for valid packets. Of course it differs depending on the device you’re working with and your specific needs. USB does have specific communications protocol defined, one of them being command based, like the little packet just mentioned. But with USB, you’re able to get the whole command and parameter together at once, with serial you have to create the protocol yourself, buffer, and parse the data. My previous serial post has more info under the header “Protocol Development”.

Buffering Incoming Data
Since bytes may come in at any time, buffering incoming data is critical. For example, you may send a command out to your device, and the response back to the PC could trigger a single DataReceived event with all the 30 bytes of response data in the receive buffer. Or more likely, it could be any number of separate triggers of the DataReceived (up to the number of bytes received), like 4 triggers, first with 2 bytes, then 15 bytes, then 1 byte, then 12 bytes. Don’t look for a complete response in a single DataReceived call, instead:
1. buffer the incoming data
2. then scan your buffer to find complete data
3. remove the used data from the buffer

To buffer incoming data, use a coding pattern like this:
(download the code SerialComBuffering.zip)

using System;

using System.IO.Ports;

using System.Collections.Generic;

namespace SerialComBuffering

{

class Program

{

    SerialPort com = new SerialPort(SerialPort.GetPortNames()[0],

      9600, Parity.None, 8, StopBits.One);

    List<byte> bBuffer = new List<byte>();

    string sBuffer = String.Empty;

    static void Main(string[] args)

    { new Program(); }

    Program()

    {

      com.DataReceived +=

        new SerialDataReceivedEventHandler(com_DataReceived);

      com.Open();

      Console.WriteLine("Waiting for incoming data...");

      Console.ReadKey();

    }

    void com_DataReceived(object sender,

      SerialDataReceivedEventArgs e)

    {

      // Use either the binary OR the string technique (but not both)

      // Buffer and process binary data

      while (com.BytesToRead > 0)

        bBuffer.Add((byte)com.ReadByte());

      ProcessBuffer(bBuffer);

      // Buffer string data

      sBuffer += com.ReadExisting();

      ProcessBuffer(sBuffer);

    }

    private void ProcessBuffer(string sBuffer)

    {

      // Look in the string for useful information

      // then remove the useful data from the buffer

    }

    private void ProcessBuffer(List<byte> bBuffer)

    {

      // Look in the byte array for useful information

      // then remove the useful data from the buffer

    }

}

}
Q: How do you detect when a device is connected or disconnected?
Simply put, the device usually start or stop sending data. There is no built in events on a connect or disconnect. But there are a few tricks you can do, if you’re creating the serial device you have more options. I’ve had my devices (and PC apps) send a constant “are you there” set of bytes, like 00 00 11 11 00 00 hex (I’d use a ‘are you there’ custom ‘packet’ as in Q12 above) till a device on the other end responds. You could also use hardware, that’s what some of the other signals lines are for (CDC, DSR, RTS, CTS, RI), you can tie one of these high and then catch an event when the line goes high you know there’s a device there, when it goes low the device is gone.
Q: How can I get more support? What are my support options?

Read this FAQ section! :)
You can try leaving a comment below. Perhaps someone knows the answer
Try doing a search and look for other content. "SerialPort C#", "Serial Com C#", "serial port .net"
Post a question in the .NET Base Class Library in MSDN Forums

Define 'Axiom Postulate Theorem Corollary Hypothesis'

2005-03-21T20:43:00Z

When explaining to a friend of mine some of the fundamentals of mathematics, I found myself giving definitions of these base terms. A quick search with Google returned this great excerpt that efficiently and eloquently defines the words and relations, and merits posting here.

The words axiom and postulate are synonymous in mathematics. They are statements that are accepted as true in order to study the consequences that follow from them. Suppose that you were studying a deductive system called Jabbermetry and the words toves and mome appeared in the statement For every two toves P and Q there is a unique mome PQ that contains both P and Q. Given no other information, you would be unable to prove that this statement is true. In fact, this statement defines an important relationship between toves and momes; it is an axiom or postulate of Jabbermetry. Notice that if you are informed that Jabbermetry actually means Geometry, toves means points, and mome means line, the statement becomes more familiar: axiom 1: For every two points P and Q there is a unique line PQ that contains both P and Q. Do not be misled by your familiarity with points and lines, however. It remains that this statement cannot be proven since you are given no other information and is thus an axiom or postulate.

Three other terms that occur in the hierarchy of deductive reasoning are theorem, corollary, and hypothesis. A theorem is a statement that is a logical consequence of axioms and other theorems. A theorem, unlike an axiom or postulate, exists only if a proof can be given for the statement. For example, if you allow the additional axioms axiom 2: There exist three points not all in one line, and axiom 3: Two lines L and M are parallel if they do not intersect or if L = M, then you can show that the statement Two distinct lines intersect in at most one point is a consequence of axioms 13; the proven statement is a theorem. A corollary is a trivial theorem, that is, a theorem that so closely follows another axiom or theorem that it practically does not require a proof. For example, a corollary of axiom 3 above is If L is a line, then L is parallel to itself. The proof of this corollary is the definition of equals: L = L. Finally, a hypothesis is a statement that has not been proven but is expected to be capable of proof. For example, you may hypothesize If point B is between points A and C, then point C is not between points A and B. This is equivalent to a conjecture. If this statement does not follow from your present system of axioms, you may wish to include an additional axiom or make the hypothesis an axiom itself and see where it leads you. For the hypothesis given above, you may want to introduce an axiom that establishes a coordinate system.

Thus, axioms and postulates form the roots of a particular deductive system; theorems and corollaries are the logical consequences that fill out the deductive system; hypotheses drive theoretical development forward.

From: The American Heritage Book of English Usage

Ballmer Dancing Developers Conference Video

2005-03-19T12:39:00Z

At one of the developer conferences (late 90s, early 2000s?), Steve Ballmer, CEO of Microsoft, came out on stage saying 'Developers' over 15 times before his voice went out. Being a developer myself, I think this is cool. At the Microsoft company meeting that followed, I remember talk among us employees whether he was going to come out on stage saying another word repeatedly (he didn't that time). Here they are...

Ballmer Saying 'Developers' Repeatedly
Ballmer Excited at Another Conference
Remix of the Two Video Clips w/ Music
This is really cool! In a geeky way...

Ballmer Sells Windows v1.0 TV Video Ad

2005-03-19T12:30:00Z

Steve Ballmer, CEO of Microsoft, can be seen here in an early days of Microsoft in this TV ad selling Windows v1.0. It is a facinating, and entertaining, video.

Get a load of the 286 computer w/ IBM EGA monitor! Wow, that brings back memories... The 'card filer' could use some sample data, it isn't clear what it does here. Looks like the control panel was a bit small in those days. Hehe, I actually remember trying out Reversi. :)

Congrats to Jeffrey Palermo, MCAD

2005-02-20T08:50:00Z

Congratulations to my friend Jeffrey Palermo on becoming a Microsoft Certified Application Developer (MCAD)!

Jeff's making great progress on his MS certifications and is headed towards a MCSD & MCT.

US Patent Plaque

2005-02-20T06:39:00Z

Between high school and college (at Texas A&M Univ.), I spent a year in Sandpoint, Idaho, working on a national biomedical smart card system. My Dad was working for a sister company at the same time on a portable home cholesterol monitor which interfaced with the smart card. The company, Lifestream, filed for a US Patent on the cholestoral monitor and medical tracking system and it was granted.

It was a great experience working with smart cards and creating a medical record tracking system. Smart cards at the time were desined for financial purposes, so it was a fun challange to create a flexible system on the cards for medical data. The smart card inserts into portable medical devices, like the cholesterol meter, glucose monitors, blood pressure cuffs, etc. Requiring the user's PIN, the medical device gets data from the smart card, saves its results to the card, then the user puts the card into a PC to save and analyse the data.

My Dad recently gave me this plaque to commemorate the patent being issued. Thanks Dad!

The plaque my Dad sent me to memorialize our accomplishment.