MRI of Texas

What is an iButton?

The iButton¬ is a 16mm computer chip armored in a stainless steel can. Let’s start with the package. Because of this unique, durable package, up-to-date information can travel with a person or object. The steel button is rugged enough to withstand harsh outdoor environments; it is durable enough for a person to wear everyday on a digital accessory like a ring, key fob, wallet, watch, metal card or badge (all of which, incidentally, you can purchase from this site).What is an iButton?

Now let’s move to the computer chip inside the package. There are multiple different iButtons available. Each starts with a guaranteed-unique registration number engraved in the silicon. From there, iButtons branch out into three different types:

1. Memory iButton . 64K and beyond of computer memory stores typed text or digitized photos. Information can be updated as often as needed with a simple, momentary contact. Some memory iButtons contain a real-time clock to track the number of hours a system is turned on for maintenance and warranty purposes (DS1994); a temperature sensor for applications where spoilage is a concern, such as food transport (DS1921); or a transaction counter that allows the iButton to be used as a small change purse (DS1963).

2. Java™-powered cryptographic iButton . A microprocessor and high-speed arithmetic accelerator generate the large numbers needed to encrypt and decrypt information. The Java-powered iButton adds its complete cryptographic circuitry to a Java Virtual Machine (VM) that is Java Card™ 2.0-compliant, enabling the world’s large pool of Java programmers to tap into a powerful development tools to get an application up and running quickly. The Java-powered iButton’s greatest promise lies in its capacity to interact with Internet applications to support strong remote authentication and remotely authorized financial transactions. In practical terms, that means you can jump into the age of electronic commerce with both feet: your messages are sent over the Internet scrambled and can only be unscrambled at the other end by someone with an authorized iButton. By establishing a means to transmit and protect user identity, the iButton becomes the user’s digital credential.

3. Thermochron iButton. This iButton tracks time and temperature, keys to the freshness of many products. The Thermochron integrates a thermometer, a clock/calendar, a thermal history log, and 512 bytes of additional memory to store a shipping manifest.

What’s the Java-powered Ring?
Java-powered ringThe Java-powered Ring is, not surprisingly, the Java-powered iButton mounted on a jewelry-grade ring. Why a ring? The whole idea is that you wear your credential on a carefully guarded accessory, something you’ve spent your entire life practicing how not to lose; and something rugged enough to stand up to everyday wear. The memory iButton is also available in ring form: the Digital Decoder Ring. If you don’t like rings, we also offer an iButton watch, wallet, engraveable metal card, and key fob so you can wear your iButton in the form that best suits you.

How Do I Get Information In and Out of the iButton?
Blue Dot ReceptorInformation is transferred between your iButton and a PC with a momentary contact, at up to 142K bits per second. You simply press your iButton to the Blue Dot receptor, a $15 pipeline into your PC. The Blue Dot sticks to any convenient spot on the front of your PC and is cabled to the serial or parallel port in the back.

The iButton is also the ultimate information carrier for portable applications: it can talk to desktop, laptop, and hand-held PCs, as well as a variety of hand-held reader/writer devices, including cordless models that collect data for later downloading to a PC. For a full listing of reader/writer devices available, go to iButton Partners .

How Durable is the iButton?Mud Photo
The fragile silicon chip within the iButton is protected by the ultimate durable material: stainless steel. You can drop it, step on it, scratch it, or wear it swimming. (Try any of those with your Smart Card and see what happens.) The iButton is wear-tested for 10-year durability.

What Can I Do With the iButton?
Mud PhotoThe iButton is ideal for any application where information needs to travel with a person or object. Affixed to a badge, key fob, watch, or ring, an iButton can grant its owner access to a building, a PC, a piece of equipment, or a vehicle. Attached to a work tote, it can measure a variety of processes to improve efficiency, such as manufacturing, delivery, and maintenance. Some versions of the iButton can be used to store cash for small transactions, such as transit systems, parking lots, and vending machines. The iButton can also be used as an electronic asset tag to store information needed to keep track of valuable capital equipment.

What Do I Need to Put Together an iButton Application?
There are four components fundamental to any iButton application:

1. iButtons
2. A host system: this can be a PC, a laptop, or a hand-held computer.
3. A reader/writer device to get information into and out of the button. This can be the Blue Dot mentioned above, a pen-style probe, or a hand-held.
4. A layer of software to interface iButtons to computers and produce the desired information in the desired format. For all memory iButtons and the Dallas O/S crypto iButton, iButton-TMEX is a software platform on which to build applications. TMEX removes the tedious low-level programming of drivers and utilities. Software needed to interface to the Java-powered iButton is downloadable from this site at no charge.

How Much Does it Cost to Build a Simple iButton Application?
About $25 and your programming time. iButtons range in cost from $2.21 to $24 in quantities of one; large quantities are discounted. The Blue Dot receptor, a simple reader/writer device, costs $15. The software is free from this web site. You can check out our shopping cart to get exact costs for all components, along with quantity discounts.

I Don’t Want to Build My Application Myself. Do You Provide Turnkey Solutions?
Dallas Semiconductor has partnered with a number of companies called Authorized Software Developers (or ASDs for short), who have developed turnkey iButton systems for access control, time and attendance tracking, payroll, truck fleet maintenance, manufacturing control, fare collection, and more. The ASDs can also develop custom iButton applications for you. iButton Partners is an online catalog that puts you in touch with ASDs.

Who’s Using the iButton?
With 41+ million iButton currently in circulation, the list of users is very long. Some of the larger installations of memory iButtons include the U.S. Post Office, which has iButtons affixed to blue corner mailboxes nationwide so they can do the tracking needed to ensure on-time delivery of the mail. Ryder has its entire truck fleet fitted with iButtons that track vehicle maintenance. Citizens of Istanbul, Turkey, store digital cash in the iButton, using the device as a small change purse on their mass transit system.

The U.S. Postal service has approved the cryptographic iButton as a Postal Security Device to be used in its PC Postage program that allows individuals to download postage off the Internet and print it from their own printers. iButton Applications highlights a wide variety of iButton applications.