DEMOKITCRX14 STMicroelectronics, DEMOKITCRX14 Datasheet - Page 32

• Manufacturer Part Number: DEMOKITCRX14
• Description: RFID EVALUATION KIT ISO14443-B
• Manufacturer: STMicroelectronics
• Type: Development kitr

Specifications of DEMOKITCRX14

• Contents: CD-ROM, CRX14 Board, USB Transceiver, Samples and Documentation
• Processor To Be Evaluated: CRX14
• Interface Type: I2C
• Operating Supply Voltage: 5 V
• For Use With/related Products: CRX14
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 497-3704

Tag access using the CRX14 coupler
Figure 29. Standard TAG command: answer frame reception
Figure 30. Standard TAG command: complete TAG access description
7.2
32/47
I²C
RF
I²C
RF
START
TAG
SOF
SOF
Device
Select
Code
Write
Data 1
Anti-collision TAG sequence
The CRX14 can identify an ST short range memory using a proprietary anti-collision
system.
Issuing an I²C Write command to the Slot Marker Register
TO automatically generate a 16-slot anti-collision sequence, and to store the identified
Chip_ID in the Input/Output Frame Register, as specified in
After receiving the Slot Marker Register I²C Write command, the CRX14 generates an RF
PCALL16 command followed by fifteen SLOT_MARKER commands, from
SLOT_MARKER(1) to SLOT_MARKER(15). After each command, the CRX14 waits for a
tag answer. If the answer is correctly decoded, the corresponding Chip_ID is stored in the
Input/Output Frame Register. If there is no answer, or if the answer is wrong (with a CRC
error, for example), the CRX14 stores an error code in the Input/Output Frame Register. At
the end of the sequence, the host has to read the Input/Output Frame Register to retrieve all
the identified Chip_IDs.
Register
TAG
Data
Address
I/O
Data 2
Request
TAG
Data
Length
Frame
Data
TAG
Data
Request
Frame
Bytes
Data P
TAG
Data
STOP
SOF
Characters
CRC
TAG
CRC
Request
Frame
Doc ID 8880 Rev 4
CRC
TAG
CRC
CRC
EOF
EOF
<-->
TAG
EOF
T 0
<-->
T 1
S
T
A
R
T
SOF
Device
Select
Code
Answer Frame
Characters
TAG
Register
Address
Output
Input/
01h
(Figure
Answer
Length
Frame
Table
P
CRC
EOF
START
Data 1
TAG
Data
4.
16) causes the CRX14
Device
Select
Code
Read
TAG
Data
Data 2
Answer
Length
Frame
TAG
Data
Data
Request
Frame
Bytes
Data P
TAG
Data
ai09262
CRX14
ai09261
STOP
S
T
O
P