Electronic Key Touch Momery iButton DS1990/TM1990/RW2004
What is an iButton?
---- An iButton is a computer chip which is enclosed in a 16mm thick durable weather resistant stainless steel can. Because of their small size and extreme durability, iButtons can travel virtually anywhere.
How does an iButton communicate?
The iButton is a slave device and requires a master to initiate communication to it. A master can be a PC or a micro processor. With the master constantly polling the iButtons, communication to iButtons can be started by a simple touch to a 1-Wire interface called a Blue Dot Receptor. Every iButton has a unique 64-bit serial number, which gives it a unique 1-Wire network address.
What are iButtons being used for?
iButtons are frequently attached to key fobs, rings, watches, or other personal items for applications such as access control to buildings and computers. Additionally, iButtons are commonly mounted to storage crates, trucks, and other equipment for asset management. Furthermore, iButtons are mounted to refrigeration units, outdoor environments, and even to animals for various data logging tasks
Please kindly advise the type when you inquiry or order.
|Specification of iButton Key|
TM1990. TM1990A-F5 -read only
RW1990, RW2004 - read &write
|Feature||Waterproof, shakeproof ,heat-resistant,dust-resistant|
|Application||Access Control |
|read time||350,000 times|
How long does an iButton last? How durable is it?
Thanks to sealed stainless steel, you can drop it, step on it, or scratch it. The iButton is wear-tested for 10-year durability and a million hot contacts.
What are the basic components I need to work with iButtons?
You need four things to work with iButtons:
2. A host system -- a PC, a laptop, or a hand-held computer.
3. A 1-Wire Adapter and iButton Probe to get information into and out of the button.
4. Software (links below)
1-Wire for Windows (TMEX)
1-Wire Public Domain Kit
1-Wire API for Java
What's the most popular iButton accessory?
Nearly 2 million public transit passengers in Istanbul carry their iButton on a plastic key fob. It's the simplest way to mount an iButton for applications that require only momentary contact. After snapping in the iButton, the fob can be attached to a key ring. Fob types vary to fit the depth of the iButton they will carry and offer the choice of angled or straight shapes.
How can I use iButtons for Web site access?
With 1-Wire API for Java, a programmer can write a simple Java applet. Keep in mind that it must be digitally signed.
What is the ROM ID number?
The ROM ID number is a unique ROM code that is 64 bits long. This number is factory lasered into each 1-Wire device. This assures absolute traceability because no two parts have the same number. The first 8 bits are a 1-Wire family code. The next 48 bits are a unique serial number. The last 8 bits are the CRC of the first 56 bits.
as a protective device to prevent reverse engineering or copying of a product.
Some of the iButtons have two package types listed, F3 and F5. What is the difference?
The only difference between the F3 and F5 is the height of the can. The F3 is 3.10mm and the F5 is 5.89mm.
If humans are going to be interfacing with the iButton (picking it up), the F5 can is easier to handle.
Can more than one iButton co-exist on the 1-Wire line?
Yes, due to the unique ROM ID number in each iButton, a number of iButtons can be on the same 1-Wire line and each can be addressed individually.
What is the iButton made of?
The iButton metal "can" is Type 305 Stainless Steel and the insulating grommet is molded from a polypropylene homopolymer resin that has a carbon black additive to inhibit breakdown due to ultraviolet light.
Can the markings on the iButton be changed? Can the iButton come with a different company logo on it?
Yes, it is possible to get the iButton with custom branding.