Protocols
A protocol is a way of encoding data on an RFID tag. This is not the same as the tag type. For example, we support the T5577 tag type, which can be programmed
with any of the protocols which we support. We also support read-only tags which have been programmed in any of these protocols.
We support reading and writing in 3 protocols with the 1024:
EM4100
EM4100 (also known as EM4102) is the protocol that all previous PhidgetRFID readers have supported. This protocol encodes 40 bits of arbitrary data. Readonly tags that are factory programmed with this protocol are supposed to be unique.
Phidgets represents this protocol as a 10-digit hex string (include leading 0's) ie. "0087f3bc91". This is the format to use for writing new tags, and to expect from the
tag events.
ISO11785 FDX-B
ISO11785 defines tags used for animal ID. If you have a pet cat / dog, chances are fairly high that they have one of these tags implanted. FDX-B refers to the way
that the ISO11785 data is encoded on the RFID tag, and is the industry-standard encoding scheme.
This tag consists of a 10-bit country code and a 38-bit unique ID.
The country code is ISO 3166 (http://en.wikipedia.org/wiki/ISO_3166-1_numeric) . The '999' code is set aside for testing.
The unique ID is 38-bit unsigned, so that's a range of 0 - 274,877,906,943.
Phidgets represents this protocol as a 15-digit decimal number string - concatenated 3-digit country code and 12-digit id. ie. "999000000000123" would represent
the testing country code and an id of 123. please note that the 12-digit id part cannot exceed the 38-bit maximum integer value of 274,877,906,943.
Note that Animal tags with a valid country code are supposed to be unique. Of course, with the 1024 you can freely copy an existing Animal Tag.
PhidgetsTAG
The PhidgetsTAG protocol is an internal protocol only supported by the PhidgetRFID 1024.
This protocol allows storing an ASCII string, up to 24 characters. ie. "I am a Phidgets Tag!"
The ASCII data must be 7-bit, so no extended ASCII support, but standard text is all supported (as well as control codes).
Controlled Outputs
The PhidgetRFID has four outputs - two of which are available to the user, and two of which are for
internal control of the Phidget board only. Output 0 is a +5V source from the USB bus through a PChannel MOSFET with less than one ohm impedance. This can be used to switch a TTL or CMOS
device, or it can be used to drive a 5VDC relay such as the Aromat JS1-5V. Output 1 is an LED drive
output at 5VDC with maximum 15mA of available current (250 ohm CMOS output). Both Output 0 and 1
are available in hardware at the terminal blocks on the PhidgetRFID board. If Output 0 is used to drive a
relay, a fast clamping diode must be placed across the relay drive pins as shown in the diagram on the right.
Not doing so can result in permanent damage to the PhidgetRFID board.
1024 Outputs
Output Function Connection
0 +5VDC Source Terminal Block
1 External LED Drive Terminal Block
LED Internal LED Drive Internal Only
RF Enable RF Antenna Enable Internal Only
Interfering Signals