Setting up MicroLan for Dallas 1-Wire hardware

The Bad Old Days

You should only be reading this page if you have already been through my main "Set up for 1-Wire" page. The page you are reading now is some details of a 2006 installation experience. Today, most people should not encounter any of the things below.

On a previous occasion (back in 2006), as I worked through the set up process, blow by blow, on a "new" machine, to be sure I told you everything, I did it as is set out below. It might have been better to install the TMEX 3.22 package first (to get the iButtonViewer) and THEN install the version 4 TMEX package... but I doubt that is going to be important to many readers.

Set up your PC, get it running normally.

Copy the 1-Wire setup .msi to the PC's desktop, run it.

You may, on an old machine, encounter a problem due to a too old "Windows Installer Service".

At I found good help with that issue. (It is a general problem, not specific to 1-Wire)

One solution which may suit your needs is the

Microsoft's Windows Installer 2.0 Redistributable for Windows 95, 98, and Me page...

... (For how much longer??)...

... which gave me a download button for InstMsiA.exe, which ran nicely, even on a machine with no internet connection. After running that, install_1_wire_drivers_v400.msi ran nicely.

BE CAREFUL... you need to decide if you want

- 1-Wire API for .Net, etc, and


Re- the OWCOM.API, to quote the Dallas site again:

"Warning: Do not install the COM object if you
do not have the Microsoft Java Virtual Machine (now
unsupported by Microsoft) installed on your system.
To avoid installing the COM object, de-select it
when prompted during the installation process."

I did NOT install either.... but your needs and circumstances may be different.

Before the end of this tutorial, I expect to have the (free from Dallas) iButtonViewer and OneWireViewer working, which is enough to get the flavor of working with 1-Wire chips. I suspect that many programs will run happily without either of the optional components.

During the install, it tells you first to unplug any 1-Wire USB adapter you may have (do that); it then says to plug any you have in. I think you can plug it in later... don't worry about "will this be possible?" (But you can worry about whether I'm right!)

There are some other steps in the install process that are, I hope, clear from the on screen prompts.

Re-boot after the install completes.

Check that your "Programs" start menu entry has gained...

"1-Wire Drivers" (badly named, in my view), with, within it:

The first is an application that, in essence, creates an ini file used by various 1-Wire apps. It is concerned with setting things up in your machine so that it uses the adapter you have plugged in, and so that it looks for it on the right port. You shouldn't need to run it now... it was "run" during the install process... but you can re-run it (if it doesn't pop up by itself) if you change adapter type or port.

The two .htm entries will NOT take you out onto the internet... they merely display some information from your hard disc, using your internet browser to display it.

You COULD press ahead at this point to the "joys" of installing the OneWireViewer.

If you can still get it by the time you read this, however, I'd recommend that you first install and get working the simpler, older (less capable... but still useful!) "iButton Viewer.

At August 06, you could get that by going to this link and downloading...


Legacy Software
The following are links to legacy 1-Wire Drivers
installations (formerly known as iButton-TMEX).

Download Version 3.22 (TMEX API only.)

* Drivers with iButton Viewer (self-extracting

(2.3meg, tm322_32.exe)

.. and running it. (Dalsemi, the domain that is at, is another name for "Dallas", i.e. "Dallas Semiconductor", now part of Maxim.)

In a perfect world, I'd do that on a "scrap" computer, and copy over just the "good stuff", but I seem to have got away with running both "setup" packages. The second should add a iButton-TMEX item to your Start menu programs panel, with sub-entries....

Launch on the iButtonViewer.

It should show you the devices connected to your MicroLan. For some more recent devices, it may only show you the chip's ID (One of the "magic" bits of the 1-Wire family is that every chip has a unique ID... a string of 16 hex digits.) Your adapter may have a 1-Wire chip in it, so don't be surprised if you see an "extra" device,

If you have one or more DS1820(s) on your MicroLan, iButtonViewer is sufficient to read the temperature from it (them).

iButtonViewer may be all you need. If you have application software from others which you want to use, you are ready to try it.

I'm hoping (but am not sure) that the install of tm322_32.exe after the install of the version 4 package has not/ will not "wreck" the version 4 install. All seems okay on my system....


Moving on to the "joys" of installing the OneWireViewer...

Remember: This page is about my experiences with a set up back in 2006. My page for current set ups is the one to look at first. In November 2009, the OneWireViewer install was part of the drivers install.

Again, go to this link at Dallas and go down to the OneWireViewer section.



The machine I was doing this test on had the Microsoft Java installed on it. After half an hour of searching the web, I found out...

a) Microsoft agreed in a settlement to abandon it's Java work.

b) MS had a MS Java removal tool.

c) That tool is no longer available for download from the MS site. (There may be a way to order a copy.)


Found a tool...

ver 6.00.2448.0000 (Lab04_N(rahulth).010206-1320)

....supposedly from MS... but how hard to spoof that? WHY DOESN'T MS MAKE THE THING AVAILABLE????? WHY DON'T OUR USELESS GOVERNMENTS make THEM MAKE IT AVAIL?

Anyway... it passed a virus scan, I ran it.

Messages said MS Java elements would be removed OR DISABLED... WHY NOT REMOVE???

Found big folders, registry entries left behind. If you are in same boat, good luck to you. Taking something like this out is always risky.


Anyway... back to the story....

iButtonViewer, in my opinion, is a much nicer, better behaved application. However, it does not support all 1-Wire chips, 'though it can detect them all, give you the chips' IDs.

Dallas has decided that "the way to go" is OneWireViewer.

I dislike it because it requires that you get involved with Java. Not a terrible thing... a bit like have Adobe Acrobat Reader on your system... but it DOES entail an extra layer of hassle, overhead, etc.

If you are happy to have Sun and friends "just do things" to your system, there are easier routes than the one I'm going to explain below... if your machine is online, via broadband.

My "complicated" route may be more conservative, may give you more control over what is going on in our computer.

Download the Java Runtime Environment, and all the bits that you have to have with it.

For this, go to this link at From there *I* would go to the manual download page, do things that way. You may prefer to fall in with's recommended solution. Furthermore, I like the Offline Manual download... 16Mb at August 06 for Java 5. Doing it this way, you just download the big file, save it (for the next machine you want to set up, or to rebuild the present one after a crash), and then double click on the file to do the install.... in other words, the Offline Manual install is an "ordinary" install.

Anyway... if like Alfie Doolittle you managed to find "A little bit of luck..." you should get your Java RTE set up somehow, without too much hassle.

I did a "custom" install, installing only the J2SE rte, which, confusingly enough, is also called rte 5.0. I allowed it to register itself with my Internet Explorer.

Once the RTE is installed, you should find a Java applet in the Control panel/ settings page. Windows Explorer should NOT have a "Java Console" item in the View menu (that's a sign that you have the MS Java variant... which was withdrawn to settle a lawsuit.) You will not see anything new in your Start | Programs menu.


On to OneWireViewer!!!

The Java community offers something called "Java Web Start" which, dinosaur that I am, I don't like. If you like it, feel free to use it, but here I will present what I consider a better way to proceed, based on things endorsed on the OneWireViewer page....


- OneWireViewer.jar, and
- OneWireAPI.jar

They are downloadable from this Maxim page. Be sure to select "Save to disc". Put them on your hard drive in a Good Place. If you know more about Java than I do, please tell me where that would be. I created a folder in program files for them, and put a little text file called 1WireLauncher.bat in it. That file consisted simply of the following line. (If it appears as two or more lines on your screen, that is merely due to word wrap.)

java -cp "OneWireViewer.jar;OneWireAPI.jar" OneWireViewer

I then created a shortcut to the bat file.

Things didn't quite work at first. If you installed the TMEX 3.22 package first, and then put the version 4 package on top of 3.22, you might find that your system IS ready to work at this stage. Because I did the TMEX 4 first, and then the TMEX 3.22, I had, at this point, to re-install the version 4. During that, I got a message saying that the owapi.dll failed to register. That suited me fine. Ignored the message; clicked "continue".

When I double clicked on the .bat file, a DOS window came up, but after that, it seemed nothing was happening. However, after a worrying delay (30 seconds?) finally things started happening.... a window opened titled "1-Wire API for Java Setup Wizard." I answered the questions about to my adapter type and port, and eventually I was rewarded with the OneWireViewer!!!

Well! It certainly seemed like a lot of work, written out in detail like that, and with the rough edges that arose in 2006. On an install in November 2009, to an XP machine, all went very smoothly, very simply. It isn't so bad, really... and the world of 1-Wire is full of all sorts of fun possibilities, which can more than make up for any little "joys" you have to go through to get started!

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