The Java Ring is a stainless-steel ring, 16-millimeters (0.6 inches) in diameter that houses a 1-million-transistor processor, called an iButton. The ring has 134 KB of RAM, 32 KB of ROM, a real-time clock and a Java virtual machine, which is a piece of software that recognizes the Java language and translates it for the user's computer system.
At Celebration School, the rings have been programmed to store electronic cash to pay for lunches, automatically unlock doors, take attendance, store a student's medical information and allow students to check out books. All of this information is stored on the ring's iButton. Students simply press the signet of their Java Ring against the Blue Dot receptor, and the system connected to the receptor performs the function that the applet instructs it to. In the future, the Java Ring may start your car.
Mobile computing is beginning to break the chains that tie us to our desks, but many of today's mobile devices can still be a bit awkward to carry around. In the next age of computing, we will see an explosion of computer parts across our bodies, rather than across our desktops. Digital jewelry, designed to supplement the personal computer, will be the evolution in digital technology that makes computer elements entirely compatible with the human form.
The Java Ring, first introduced at Java One Conference, has been tested at Celebration School, an innovative K-12 school just outside Orlando; FL.The rings given to students are programmed with Java applets that communicate with host applications on networked systems. Applets are small applications that are designed to be run within another application. The Java Ring is snapped into a reader, called a Blue Dot receptor, to allow communication between a host system and the Java Ring.
Figure 1: prototype of stainless steel java ring.
In the summer of 1989, Dallas Semiconductor Corp. produced the first stainless- steel encapsulated memory devices utilizing the Dallas Semiconductor 1-Wire communication protocol. By 1990, this protocol had been refined and employed in a variety of self-contained memory devices. Originally called "touch memory" devices, they were later renamed "iButtons." Packaged like batteries, iButtons have only a single active electrical contact on the top surface, with the stainless steel shell serving as ground.
Data can be read from or written to the memory serially through a simple and inexpensive RS232C serial port adapter, which also supplies the power required to perform the I/O. The iButton memory can be read or written with a momentary contact to the "Blue Dot" receptor provided by the adapter. When not connected to the serial port adapter, memory data is maintained in non-volatile random access memory (NVRAM) by a lifetime lithium energy supply that will maintain the memory content for at least 10 years. Unlike electrically erasable programmable read-only memory (EEPROM), the NVRAM iButton memory can be erased and rewritten as often as necessary without wearing out. It can also be erased or rewritten at the high speeds typical of complementary metal oxide semiconductor (CMOS) memory, without requiring the time-consuming programming of EEPROM.
Since their introduction, iButton memory devices have been deployed in vast quantities as rugged portable data carriers, often in harsh environmental conditions. Among the large-scale uses are as transit fare carriers in Istanbul, Turkey; as maintenance record carriers on the sides of Ryder trucks; and as mailbox identifiers inside the mail compartments of the U.S. Postal Service's outdoor mailboxes. They are worn as earrings by cows in Canada to hold vaccination records, and they are used by agricultural workers in many areas as...