Data Sheet

ManualsBrandsParallax ManualsRFIDRFID Read/Write Module - USB

Web Site: www.parallax.com

Forums: forums.parallax.com

Sales: sales@parallax.com

Technical: support@parallax.com

Office: (916) 624-8333

Fax: (916) 624-8003

Sales: (888) 512-1024

Tech Support: (888) 997-8267

RFID Read/Write Module, Serial (#28440)

RFID Read/Write Module, USB (#28540)

Designed in cooperation with Grand Idea Studio (www.grandideastudio.com

), the Parallax Radio

Frequency Identification (RFID) Read/Write Module provides a low-cost solution to read and write passive

RFID transponder tags up to 4 inches away. The RFID transponder tags provide a unique serial number

and can store up to 116 bytes of user data, which can be password protected to allow only authorized

access.

The RFID Read/Write Module can be used in a wide variety of hobbyist and commercial applications,

including access control, user identification, robotics navigation, inventory tracking, payment systems, car

immobilization, and manufacturing automation. It is available in two versions: A TTL-level serial interface

for use with a microcontroller and a USB interface for direct connection to a computer.

Features



Low-cost method for reading and writing passive, 125 kHz RFID transponder tags

 Up to 116 bytes of user data storage on a single tag

 Optional security features prevent tag from being read or written without password

 Bi-color LED for visual indication of status

Summary of content (10 pages)

PAGE 1
Web Site: www.parallax.com Forums: forums.parallax.com Sales: sales@parallax.com Technical: support@parallax.com Office: (916) 624-8333 Fax: (916) 624-8003 Sales: (888) 512-1024 Tech Support: (888) 997-8267 RFID Read/Write Module, Serial (#28440) RFID Read/Write Module, USB (#28540) Designed in cooperation with Grand Idea Studio (www.grandideastudio.
PAGE 2
Key Specifications    Power requirements: 200 mA Communication: 9600 baud, 8 data bits, no parity, 1 stop bit, non-inverted. 5V TTL, (28440) or USB (28540) PCB Dimensions: 2.45 x 3.25 x 0.22 in (62 x 83 x 5.5 mm) Dimensions RFID Tag Compatibility The RFID Read/Write Module works exclusively with the EM Microelectronics EM4x50 1kbit R/W transponder tags.
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Connection (Serial) The RFID Read/Write Module Serial version easily interfaces to any host microcontroller using only four connections (VCC, SIN, SOUT, GND). Pin Pin Name Type Function 1 VCC P System power. 5V DC input. 2 SIN I Serial input from host. 5V TTL-level interface, 9600 bps, 8 data bits, no parity, 1 stop bit, non-inverted. 3 SOUT O Serial output to host. 5V TTL-level interface, 9600 bps, 8 data bits, no parity, 1 stop bit, non-inverted. System ground.
PAGE 4
Usage There are many ways to use the RFID Read/Write Module and associated tags, but the three most common are as follows: 1) Read Only: Read the tag’s unique, non-changing 32-bit serial number 2) Read/Write: Read from and write up to 116 bytes of publicly accessible user data on the tag 3) Read/Write (Protected): Read from and write up to 116 bytes of password-protected user data on the tag. In this mode, you must enter the correct 32-bit password in order for read and write operations to be successful.
PAGE 5
Command Set Examples shown are for the RFID Read/Write Module Serial version connected to a microcontroller (BASIC Stamp 2).
PAGE 6
0x05: RFID_Protect Enable (lock) or disable (unlock) the tag’s password protection. Input: Mode (1 byte), 0x00 to unlock, 0x01 to lock Output: Status byte (1 byte) Example: SEROUT RFID_TX, Baud, ["!RW", RFID_Protect, 1] SERIN RFID_RX, Baud, [err] ' Lock the tag ' Get status byte Note: When the tag is locked, a successful login using the RFID_Login command is required before you can enable/disable password protection, change the tag’s password, or read/write to the tag.
PAGE 7
Error Checking The RFID Read/Write Module responds to each command with a single-byte status/error code in hexadecimal format followed by any returned data, if applicable. In most standard implementations, the user will repeatedly call the desired function until the ERR_OK status byte is returned, indicating that the function successfully completed with no errors.
PAGE 8
ADDR_Serial is a unique, read-only serial number with one of 232, or 4,294,967,296, possible values. It cannot be changed by the user. ADDR_DeviceID is a read-only value used to identify the specific tag family (for example, EM4150). The 32-bit value contains a family code, version code, reserved/unused bits, and a checksum value. It cannot be changed by the user. Further details of the EM4x50 tag can be found at: www.emmicroelectronic.
PAGE 9
RFID Technology Overview Material in this section is based on information provided by the RFID Journal (www.rfidjournal.com). Radio Frequency Identification (RFID) is a generic term for non-contacting technologies that use radio waves to automatically identify people or objects. There are several methods of identification, but the most common is to store a unique serial number that identifies a person or object on a microchip that is attached to an antenna.
PAGE 10
Documentation and Example Code The following materials are released under the Creative Commons Attribution 3.0 United States license (http://creativecommons.org/licenses/by/3.0/us/), allowing free distribution and reuse provided that proper attribution is given to the original author. The materials are posted on the RFID Read/Write Module product pages; search “28440” and “28540” for serial and USB versions, respectively, at www.parallax.