dsub: Serial Port class for C#.Net

dsub main formI’ve long held an affinity for serial ports. They’re easy to understand, easy to setup, and require no special drivers. I’ve worked on several projects over the years that have utilized serial ports, mostly in classic VB applications. Since learning Microsoft C#.Net, I’ve wanted to use it to interface with them. A few years ago I picked up a copy of Serial Port Complete Second Edition by Jan Axelson, and it’s been a tremendous help. Much of what I’ve learned has come from her book and website. I set out to develop my own serial port class based on my needs, and I’ve now finally finished it to the point where I feel comfortable sharing it. It’s called dsub, named for the D-subminiature electrical connector. I’m releasing it under an MIT license so you can download, use and modify the application and source code.

Download dsub here (Visual Studio 2010 project)

dsub uses .Net’s built-in SerialPort class, but adds some additional functionality to deal with multi-threading, error handling, etc. I won’t cover all the details of how it works, or why; for that, you should pick up a copy of Jan’s book and check out the COM_Port_Terminal application available on her website. dsub does differs in several ways from her serial port class, the most important difference being that I use the SerialPort.ReadLine method to get new data from the buffer. As a result, any serial port data that dsub reads will need a defined “end of transmission” character, such as a carriage return or line feed. This can be specified in dsub, so it’s possible to use any character. I did this because all the equipment I deal with sends data this way, and it’s easier to parse the data once I know the transmission is complete. If you have a situation where there isn’t a defined end of transmission character, then dsub won’t work. (Note: Jan’s class does not have this limitation.)

dsub Settings FormThe GUI application that’s included will read data from the selected serial port and display it in a grid. If a field delimiter is specified, it will use that to break up the data into separate columns in the grid. At the bottom of the screen, you can enter text to be sent. There is also a textbox where errors will be displayed. The application implements all the features of dsub so it provides a good example of how to use it.

If you use dsub in your application, let me know! I’d love to hear how it’s being used. I’ll also do my best to answer any questions or address any issues with it.

Update: Memory usage reporting fixed in Analog PC Stats application

Updated PC Meter application

It was brought to my attention a couple months ago by mnedix that the application I developed for the Analog PC Stats Meter was not reporting the correction Memory usage. I looked into it, and it turns out that the PerformanceCounter I was using in C# ties into the page file, not just physical memory. Apparently it was close enough to the physical memory used when I tested the program initially, because I never caught it. I just released an updated version of the application today that get the actual physical memory percentage used (you can download it here). It utilizes the GetPerformanceInfo Windows API to do this, using code developed by Antonio Bakula. This post at Stack Overflow is what led me to his solution. As the screenshot above shows, it’s now very close to what Windows reports. It’s a little off, maybe due to rounding, I didn’t have a lot of time to dig deeper. It’s close enough, at least for me! In the screenshot, I’ve got a couple textboxes that display physical available memory and total physical memory for troubleshooting.

While I’m posting, I want to point out it’s been approximately a year since I last posted on my blog, but I’m still here. The last year-and-a-half has been quite hectic for me, but I hope to get back into working on projects and sharing them on here soon! I’ve heard from a few people who have enjoyed my posts and used the information I’ve shared to work on their own projects and it’s been great hearing from them. Thanks!

pc meter header

Analog PC Stats Meter

Intro

At some point while researching microcontroller projects, I came across several people who had used Arduinos and PICs to drive analog panel meters so they would display computer stats such as CPU load, memory usage, etc.  It immediately struck me as something I just had to do.  Here it is.  My PC meter uses an Arduino microcontroller and receives the stats from a .NET Framework application I wrote in C#.Net.  It’s housed in a plastic enclosure and looks quite professional IMHO.  It was a fun project, and something I think most any computer/electronics geek would enjoy.  I love mine, and I look forward to building more.

Here it is in action:

Read on for details on the parts and tools I used, some info on the process of building the device (and the problems I ran into) and links to download the source code and meter templates.

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