Set your Windows of Linux system up to interact with Dallas 1-Wire hardware, over a MicroLan

Elsewhere on the web, I have more general introductions to MicroLan work. This web page is a keystroke- by- keystroke account of a first install of minimal system. It was written in August 2006, by which time I knew more about MicroLans than I did at the time I wrote some of my other pages.


1-Wire: The name for a family of chips which share several features. They all connect to one another using just two wires. Sometime the chip needs an additional wire supplying power, but not always. They all have unique- to- a- specific- chip IDs. In the 1-Wire family, there are sensors, actuators and storage devices. e.g. temperature sensors, ADCs, single and multi bit digital I/O devices. RAM, EEPROM, etc. ("1-Wire" is a trademark of Dallas Semiconductor)

MicroLan: A MicroLan is a bunch of 1-Wire chips connected to one another and to an adapter connected to some device which acts as the "brains" of the whole system. A simple PC (Win95 will do) is a typical controller. ("MicroLan" is a trademark of Dallas Semiconductor)

What you will need:


A PC with Linux or Windows 95 or higher.

An adapter. This you buy from Dallas, or other sources. It costs about $30. You can get one to plug into your PC (or other controller, e.g. a Microchip PIC microcontroller) via the serial, parallel, or USB port. (There are several adapter models. Each, alas, can plug in only to one sort of port! But the port choice is not critical... any program can interact with a MicroLan by whatever port has the adapter, without altering the program.)

A 1-wire chip or device containing a 1-Wire chip... let's say you have a DS1820 temperature sensor. Other things will be fine, too.

Wiring between the adapter and the chip. Don't be alarmed...the wiring is very simple, as you may have guessed from the brand name "1-Wire". Assuming you bought a demo kit, this is probably already provided. If not, look at your adapter. On the MicroLan side, there is probably an RJ-11 socket- the sort of socket used for phones in the US. Beware: Not all phone cables are suitable for connecting MicroLan modules to MicroLan adapters.


History lesson: In the early days of 1-Wire, the basic, free, useful "look at the Microlan" software tool was the iButtonViewer. In recent years, this has been replaced by "OneWireViewer". Each has its merits, but you will find it easiest, today, to start with the OneWireViewer.

Linux users: Go to this page at Dallas for the link you need to get to your TMEX drivers.... and bombard Dallas with complaints about the fact that on the "official" Dallas "drivers for 1-Wire" download page there is no mention of Linux!

TMEX drivers, ver 3.x, and iButtonViewer. At November 2009, access to these legacy products was via this link.

TMEX drivers, latest version (at 11/09: 4.02), and OneWireViewer... but this entails putting a Java run time environment (RTE) on your machine. If you really hate that idea, use the minimum set-up, as above... but...

Here follows a quote from...



The 1-Wire Drivers installation package
contains the necessary drivers and support
libraries for each of the 1-Wire adapters
available from Dallas Semiconductor Maxim,
including the new 1-Wire USB adapters (DS9490).
The current release of 1-Wire Drivers supports
Microsoft 32-bit Windows. This includes
Windows XP, ME, 2000, 98, NT (no USB support),
and 95 (no USB support).

....end quote. The quote is a little dated. Vista is also supported, and I have no doubt that Windows 7 will follow soon. The public transport in Istanbul is accessed via 1-Wire devices. (A "key fob" device is used to hold "money" for metro, tram, bus fares.)

Linux is also supported, by the way, although you wouldn't know that from the download page. Shame on Dallas!

Here's a link to a Dallas download page. In early November 2009, I set up a Windows XP machine "from scratch", using that link. (Having set up many machines over the years, going back to when Windows 95 was bleeding edge.)

At November 2009, for Windows XP, the current version of the drivers etc was 4.02. The file had swollen to 5MB, having been a modest 1.5 as recently as 2006. Sigh. However, part of the reason is that the OneWireViewer is now bundled. Previously, you downloaded it as a separate exercise.

I did the download for my operating system, and double clicked on the file. It was one of those "wonderful" .msi files. On an older machine, this may cause you problems, but if you use an older machine, you are probably used to that and have the necessary skills.

The set up was alarmingly quick and simple, but it did create entries in my start menu, so maybe all was well? (Subsequent experiences suggest that it did install properly.)

Getting past a detail: The OneWireViewer.htm entry in the 1-Wire Drivers x86 folder which had arisen in my start menu was just a pretty "readme" type page. You can skip that for now.

I held my breath, plugged in a 1-Wire adapter with no 1-Wire chips attached, and double clicked on the OneWireViewer.exe entry in the 1-Wire Drivers x86 folder which has arisen in my start menu. As expected for a first time run of the system, the "1-Wire API for Java setup wizard" ran. I was using a DS9097U adapter, so selected the 9097U tab. I specified COM1, as that was the only COM port listed under MyComputer|Properties|ardware|DeviceManager|Ports. I then clicked Next, and specified a poll rate of 1 per second. Clicked next, selected "Show Normal Devices". Clicked Finish, and....

The main OneWireViewer screen appeared. It, correctly, said "no device selected"... although some adapters have chips in them, so don't be alarmed if you see a "chip" "attached" when you only have the adapter attached.

At this point, I plugged a cable into the adapter, and put a voltmeter on the two wires I thought carried the 1-Wire data/power signal and the 1-Wire ground. Seeing a reassuring 5v, the correct value, I proceeded to attach a DS1820. (See my 1-Wire wiring page for details of that, and of the RJ-11 pin assignments.)

And all was well! My system was set up for 1-Wire!

For programmers: You don't need the following, unless you are a programmer, and you can use 1-Wire without being a programmer, but, programmers will also want the following: 1-Wire SDK. (Free, but not covered in this note.)


On a previous occasion (before 11/09), as I worked through the set up process, blow by blow, on a "new" machine, to be sure I told you everything. If you encountered anything strange while doing the above, my notes from that install might shed light on your circumstances, especially if you were working with an elderly machine.

I hope your set up went well. Set ups are always a bit "exciting", but 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!

Ad from page's editor: Yes.. I do enjoy compiling these things for you... hope they are helpful. However.. this doesn't pay my bills!!! If you find this stuff useful, (and you run an MS-DOS or Windows PC) please visit my freeware and shareware page, download something, and circulate it for me? Links on your page to this page would also be appreciated!
--Click here to visit editor's freeware, shareware page.--

Valid HTML 4.01 Transitional Page passed tests for compliance with INDUSTRY (not MS-only) standards, using the free, publicly accessible validator at validator.w3.org

Here is how you can contact this page's editor.
Click here to go to a general 'electronic projects' page by editor of this page.