AT88RF1354_09 ATMEL [ATMEL Corporation], AT88RF1354_09 Datasheet - Page 25

• Manufacturer Part Number: AT88RF1354_09
• Description: 13.56 MHz Type B RF Reader Specification
• Manufacturer: ATMEL [ATMEL Corporation]

Appendix A. The ISO/IEC 14443 Type B RF Signal Interface
A.1.
A.2.
A.3.
8547B–RFID–3/09
The ISO 14443 specifications refer to cards. In this section, the reader can interchange the terms “card,” “tag,” and
“transponder.”
RF Signal Interface
The AT88RF1354 RF communications interface is compliant with the ISO/IEC 14443 part 2 and part 3 Type B signaling
requirements when used exactly as described in the AT88RF1354 reference design application notes.
signaling utilizes a 10 % amplitude modulation of the RF field for communication from the reader to the card with NRZ
encoded data. Communication from card to reader utilizes BPSK load modulation of an 847.5 khz subcarrier with NRZ-
L encoded data. The 13.56 MHz RF magnetic field is continuously on for Type B communications.
Data Format
Data communication between the card and reader is performed using an LSB first data format. Each byte of data is
transmitted with a 0b start bit and a 1b stop bit as shown in Figure A-1. The stop bit, start bit, and each data bit are
each one elementary time unit (ETU) in length (9.4395 microseconds).
Each byte transmission consists of a start bit, 8 data bits (LSB first), and a stop bit. Each byte may be separated from
the next byte by extra guard time (EGT). The EGT may be zero or a fraction of an ETU. EGT cannot exceed 19
microseconds for data transmitted by the PICC. EGT for data transmitted by the AT88RF1354 PCD is zero ETUs. The
position of each bit is measured relative to the falling edge of the start bit.
Figure A-1.
Byte Format
Despite the fact that data transmissions occur LSB first, all of the commands, data, and CRC bytes in ISO/IEC 14443
and in this specification are listed in the conventional manner, with MSB on the left and LSB on the right.
Frame Format
Data transmitted by the PCD or PICC is sent as frames. The frame consists of the start of frame (SOF), several bytes
of information, and the end of frame (EOF). The SOF and EOF requirements are shown in Figure A-2.
Byte transmission format requirements for Type B communications.
Start
All bit timing is measured from the falling edge of the start bit.
Bit transitions should occur within (n ± 0.125) ETU of thefalling edge of start bit.
LSB
EGT is 0 - 57 mS for PCD transmissions.
b0
One byte transmission is 10 ETUs long plus EGT
b1
b2
13.56 MHz Type B RF Reader Specification
b3
b4
b5
b6
MSB
b7
Stop
EGT
Type B
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