DEMOKITCRX14 STMicroelectronics, DEMOKITCRX14 Datasheet - Page 27

• 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

Figure 31. Standard TAG Command: Complete TAG Access Description
I²C
RF
Anti-Collision TAG Sequence
The CRX14 can identify an ST short range memo-
ry using a proprietary anti-collision system.
Issuing an I²C Write command to the Slot Marker
Register (
matically generate a 16-slot anti-collision se-
quence, and to store the identified Chip_ID in the
Input/Output Frame Register, as specified in
5.
After receiving the Slot Marker Register I²C Write
command, the CRX14 generates an RF PCALL16
START
Device
Select
Code
Write
Figure
Register
Address
I/O
17.) causes the CRX14 TO auto-
Request
Length
Frame
Request
Frame
Bytes
STOP
SOF
Characters
Request
Frame
Table
CRC
EOF
<-->
T 0
command followed by fifteen SLOT_MARKER
commands,
SLOT_MARKER(15). After each command, the
CRX14 waits for a tag answer. If the answer is cor-
rectly 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 In-
put/Output Frame Register to retrieve all the iden-
tified Chip_IDs.
<-->
T 1
SOF
Answer Frame
Characters
TAG
from
CRC
EOF
START
SLOT_MARKER(1)
Device
Select
Code
Read
Answer
Length
Frame
Request
Frame
Bytes
CRX14
ai09262
STOP
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to