DEMOKITCRX14 STMicroelectronics, DEMOKITCRX14 Datasheet - Page 21

• 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

CRX14 ISO14443 TYPE-B RADIO FREQUENCY DATA TRANSFER
Output RF Data Transfer from the CRX14 to the
PICC (Request Frame)
The CRX14 output buffer is controlled by the
13.56MHz clock signal generated by the external
oscillator and by the request frame generator. The
CRX14 can be directly connected to an external
matching circuit to generate a 13.56MHz sinusoi-
dal carrier frequency on its antenna.
The current driven into the antenna coil is directly
generated by the CRX14 RFOUT output driver.
Figure 20. Wave Transmitted using ASK Modulation
Transmission Format of Request Frame
Characters
The CRX14 transmits characters of 10 bits, with
the Least Significant Bit (b
shown in
Several 10-bit characters, preceded by the Start
Of Frame (SOF) and followed by the End Of
Figure 21. CRX14 Request Frame Character Format
10% ASK MODULATION
OF THE 13.56MHz WAVE,
GENERATED ON THE CRX14
ANTENNA
10% ASK MODULATION
OF THE 13.56MHz WAVE,
GENERATED BY THE RF OUT
DRIVER
DATA BIT TRANSMITTED
BY THE CRX14
Figure 21.
ETU
1
0
Start
) transmitted first, as
b0
'0'
LSB
b1
b2
Transfer time for one data bit is 1/106 kHz
b3
Information Byte
b4
b5
If the antenna is correctly tuned, it emits an H-field
of a large enough magnitude to power a contact-
less PICC from a short distance. The energy re-
ceived on the PICC antenna is converted to a
Power Supply Voltage by a regulator, and turned
into data bits by the ASK demodulator. The
CRX14 amplitude modulates the 13.56MHz wave
by 10% as represented in
transfer rate is 106 kbit/s.
Frame (EOF), constitute a Request Frame, as
shown in
A Request Frame includes the SOF, instructions,
addresses, data, CRC and the EOF as defined in
the ISO14443 type-B.
Each bit duration is called an Elementary Time
Unit (ETU). One ETU is equal to 9.44µs (1/
106kHz).
b6
Figure 27.
b7
MSB Stop
b8
b9
'1'
Figure 20.
ai09250
The data
CRX14
AI10912
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