Data Logging from RS232 Device

Plug it into a printer

Or in the old days you could have written a Quick basic program to store it in a file. But uncle Bill doesn't want the proles writing software, he doesn't want user friendly computers.
He wants computers that appear to be user friendly.
Del

Proles? What does that mean; I've just never heard it before.

Abrev' for Proletariat.
Come the revolution Bill Gates will be there with my financial advisor
Del

Wow! Dell, Quick Basic?!!!!

Certainly showing your age there. I didn't know cats lived that long!!!

Quick Basic, I haven't heard those words in god knows how long.

Don't fret though, I have a Windows 98 desktop with QBasic installed on it. Don't use the QBasic, but the desktop comes in real handy for programming older controllers through the serial port.

Anyone who absolutely insists on self sufficiency can (at a fairly modest price) buy a programming language that functions within, for instance , WINXP. The one I use is very versatile, quick and powerful. I'll gladly offer name and address to anyone venturesome enough to try. BTW, it monitors both RS232 and USB ports.

If one is really wanting to explore the true power of the PC, one should investigate the Forth programming language. NOT for the feint of heart, but able to unlock the native speed of your hardware...Daunting for monitoring and manipulating ports, but, once you grasp the essentials, tremendous power.

Being definitely faint of heart, at least where Forth is concerned, I prefer a more 'normal' language. The one I've mentioned is convenient for me because it is fast and accepts multi dimensional matrices of any size within memory size restrictions. Also matrix manipulations. This helps a lot in data acquisition. This language has most direct commands that are used in communication which enables redirection of both raw and processed data. Unfortunately I'm not a shareholder.

Dovy-

I would like to have a look at the software you are recommending. By the way, SciLab has similar capabilities, although I have not used it to communicate with my meters as yet. SciLab is a free (as in beer) answer to MatLab. Also, if you are into Linux, QTDMM offers a quick and easy solution to monitoring DMM's, creating real-time plots, ets. Unfortunately, it currently works only with certain DMM's, but, since it is written in c, it is pretty easy to hack to work with most meters...

Hi cwarner,

Theoretically I'm into Linux of course, but practically...

Try looking into PowerBasic. It is not free. They have a comprehensive site explaining the varieties offered. The program is a modern and much improved descendent of the late lamented TurboBasic. It is very fast, so that quite a lot can be accomplished between data frames.

For a data acquisition project it was acquiring 4 channels at 1 Hz via an RS232 port with an on-line output of the data and its running statistics via a USB port. This was done without any need for sophisticated programming.

I have used these before for low rate data logging. Have not found anything better for the prices offered. Starter serial port and UBS versions are available. Best wishes.

http://www.dataq.com/products/startkit/di194rs.htm

Can you be a bit more specific about what you want to log.

If this device is outputting data on an RS232 port, you could simply connect it to the RS232 port of a computer and use a program like CrossTalk which will monitor the port and log the data to a text file.

I have done a lot of work on this kind of thing but you need to be a bit more specific about the application.

What about laptops that have no RS232 port? The RS232 to USB converters I've tried didn't work with older RS232 devices that don't identify themseves.

dkwarner (interesting name...)

I have had good luck with older equipment through RS232 to USB converters, including some that don't identify themselves. There are a number of tools out there that can help. If you have a specific need, contact me by private message, and maybe I can help point you in the right direction...

cwarner

I have written a macr5o in Excel that reads a multimeter over RS-232 and generates a spread sheet and real-time plot of data received,
Cool...Nice one.
Del

Yes, as Del said you can use the printer port. There is a DLL called inpout32.dll. I have used it with Delphi 7 for monitoring and controlling AC Units. You can create a text file to store your data in a format that can be exported to Excel. You can use Activex Serial Com port to write your COM program. They also have the code for VB, C++, etc.

There are many serial port loggers available for free. Some with source code, some without. The only problem you will encounter will data logging directly from the computer is that if there is a power outage or the program gets terminated, then you lose your data logger. If what you are connecting to isn't buffered, you could loose your COM port. If you are into microcontrollers, you can build a simple data logger with either Atmel or Freescale controllers.

You can also use the good old Hyperterminal to log inputs on the serial port

Serial Port Datalogging

"If what you are connecting to isn't buffered, you could loose your COM port." - your mind, your reputation, your job, etc., etc., etc..

ASYST was one of the most powerful systems for data acquisition and evaluation I`ve ever programmed. It was based on FORTH language with highest stability and least space, unfortunately overrun by these clicky-clicky graphical systems with that windows-overhead noone needs really if he/she wants a stable and reliable application.

I like Forth, because it gives me CONTROL. One can shut down all the eye candy so that the machine is dedicated to only the process at hand- and that is where the stability comes from (and stability and speed can be very important for data acquisition). I have never tried ASYST- got introduced to Forth when I decided to try to use my Palm Tungsten for some data acquisition projects- and went on to use it on my DOS boxes (I still prefer c, but that is mostly because of familiarity with c- Forth is a whole lot more powerful).

Well, there are too many unknowns... And the Op hasn't posted another responce... And one person noted that many laptops today do not have an RS232 port, even some desktops too.

Here's some suggestions for an RS232 to USB converter - down near the bottom...

http://cr4.globalspec.com/thread/40250/RS232-Cables-and-Long-Distance-Transmissions

I think there's info on why 'generic' USB to RS232 converters do not work - especially with legacy devices.

Other factors could include that this data may be needed for Validation... Too many factors un-noted by the Op.

I assume you have a data logger that you need to program. If so, do you have the support software (Windows-based perhaps?) that would enable you to program the unit? Do you have a direct connection to your logger (from your notebook PC) or do you communicate via telemetry? Either way, if you were for example, using loggers from Campbell Scientific Inc., (like me) you could - while programming, set your execution interval to 10s, write in your measurement (I/O) instruction(s) and then immediately follow it (them) up with your program control instructions (e.g. DO - set output flag high) and output processing instructions (set active storage area, sample, average, etc.). Once you've successfully compiled your program, just send it down the line to the station (logger). Wait one minute and then retrieve your six sets of test data. Other loggers (brands) most probably work along similar lines regardless of whether they execute in sequential or pipeline mode.