- 您现在的位置：买卖IC网 > Sheet目录528 > TRF7970AEVM (Texas Instruments)EVAL MODULE FOR TRF7970A
TRF7970A
www.ti.com
SLOS743K – AUGUST 2011 – REVISED APRIL 2014
in IRQ register. The MCU must set EN = H (confirm the power-up) in the time between the two IRQs,
because the internal power-up ends after the second IRQ. The type and coding of the first initiator (or
reader in the case of a tag emulator) command defines the communication protocol type that the target
must use. Therefore, the communication protocol type is available in the NFC Target Protocol register
immediately after receiving the first command.
Based on the first command from the INITIATOR, the following actions are taken:
?
?
?
?
?
6.1.3.1
If the first command is SENS_REQ or ALL_REQ the TARGET must enter the SDD protocol for 106-
kbps passive communication to begin; afterward, the baud rate can be changed to 212 kbps or 424
kbps, according to the system requirements. If bit B5 in the NFC Target Detection Level register is not
set, the MCU handles the SDD and the command received is send to FIFO. If the RF field is turned off
(B7 in NFC Target Protocol register is low) at any time, the system sends an IRQ to the MCU with bit
B2 (RF field change) in the IRQ register set high. This informs the MCU that the procedure was
aborted and the system must be reset. The clock extractor is automatically activated in this mode.
If the command is SENS_REQ or ALL_REQ and the card emulation bit in ISO Control register is set,
the system emulates an ISO14443A/B tag. The procedure does not differ from the one previously
described for the case of a passive target at 106 kbps. The clock extractor is automatically activated in
this mode. To emulate a FeliCa card, the ISO Control register must be set for passive target mode at
either 212 kbps or 424 kbps.
If the first command is a POLLING request, the system becomes the TARGET in passive
communication using 212 kbps or 424 kbps. The SDD is relatively simple and is handled by the MCU
directly. The POLLING response is sent in one of the slots automatically calculated by the MCU (first
slot starts 2.416 ms after end of command, and slots follow in 1.208 ms).
If the first command is ATR_REQ, the system operates as an active TARGET using the same
communication speed and bit coding as used by the INITIATOR. Again, all of the replies are handled
by MCU. The chip is only required to time the response collision avoidance, which is done on direct
command from MCU. When the RF field is switched on and the minimum wait time is elapsed, the chip
sends an IRQ with B1 (RF collision avoidance finished) set high. This signals the MCU that it can send
the reply.
If the first command is coded as ISO14443B and the Tag emulation bit is set in the ISO Control
register, the system enters ISO14443B emulation mode. The anticollision must be handled by the
MCU, and the chip provides all physical level coding, decoding, and framing for this protocol.
Active Target
If the first command received by the RF interface defines the system as an active target, then the receiver
selects the appropriate data decoders (ISO14443A\B reader or FeliCa) and framing option. Only the raw
(decoded) data is forwarded to the MCU through the FIFO. SOF, EOF, preamble, sync bytes, CRC, and
parity bytes are checked by the framer and discarded.
The transmitting system includes an RF level detector (programmable level) that is used for RF collision
avoidance. The RF collision avoidance sequence is started by sending a direct command. If successful,
the NFC initiator can send the data that the MCU has loaded in the FIFO register. The coding of this data
is done by hardware coders either in ISO14443A format (106-kbps system) or in FeliCa format for (212-
kbps and 424-kbps systems). The coders also provide CRC and parity bits (if required) and automatically
add preambles, SOF, EOF, and synchronization bytes as defined by selected protocol.
6.1.3.2
Passive Target
If the first command received by the RF interface defines the system as a passive target, then the receiver
selects the appropriate data decoders (ISO14443A\B reader or FeliCa) and framing option. Again, only the
raw (decoded) data is forwarded to the MCU through the FIFO; SOF, EOF, preamble, sync bytes, CRC,
and parity bytes are checked by the framer and discarded. The receiver works same as in the case of an
active target.
Copyright ? 2011–2014, Texas Instruments Incorporated
Submit Documentation Feedback
Product Folder Links: TRF7970A
Detailed Description
13
发布紧急采购，3分钟左右您将得到回复。
相关PDF资料
TRM-418-LT
TRANSCEIVER RF 418MHZ LT SERIES
TRM-900-NT
RF TXRX 915MHZ NT SERIES
TRX08GVP2540
TXRX OPT SCFF 8.5GB/S 850NM
TS-320240BRNO
TCH PANEL 140X104 RESISTIVE MONO
TS-TFT3.5Z
TOUCH PANEL 140X1.4.0 TFT
TS3-75B3
SENSOR THERMAL MOXIE NTC 75C
TSL26711FN
IC PROXIMITY DETECTOR 6-DFN
TSOP57238TT1
IC IR RCVR MODULE 38KHZ
相关代理商/技术参数
TRF7970ARHBR
功能描述:IC RFID/NFC AFE 13.56MHZ 32QFN RoHS:是 类别:RF/IF 和 RFID >> RFID IC 系列:- 其它有关文件:CR14 View All Specifications 标准包装:1 系列:- RF 型:收发器 频率:13.56MHz 特点:ISO14443-B 封装/外壳:16-SOIC（0.154"，3.90mm 宽） 供应商设备封装:16-SO 包装:Digi-Reel® 其它名称:497-5719-6
TRF7970ARHBT
功能描述:IC RFID/NFC AFE 13.56MHZ 32QFN RoHS:是 类别:RF/IF 和 RFID >> RFID IC 系列:- 其它有关文件:CR14 View All Specifications 标准包装:1 系列:- RF 型:收发器 频率:13.56MHz 特点:ISO14443-B 封装/外壳:16-SOIC（0.154"，3.90mm 宽） 供应商设备封装:16-SO 包装:Digi-Reel® 其它名称:497-5719-6
TRF7970ATB
功能描述:RFID应答器 TRF7970A Target Brd RoHS:否 制造商:Murata 存储容量:512 bit 工作温度范围:- 40 C to + 85 C 安装风格:SMD/SMT 封装 / 箱体: 封装:Reel
TRF79A6AA17LB000
制造商:Opnext 功能描述:XFP FORM FACTOR - Boxed Product (Development Kits)
TRF79A6AA18LB000
制造商:Opnext 功能描述:XFP FORM FACTOR - Boxed Product (Development Kits)
TRF79A6AA19LB000
制造商:Opnext 功能描述:XFP FORM FACTOR - Boxed Product (Development Kits)
TRF79A6AA20LB000
制造商:Opnext 功能描述:XFP FORM FACTOR - Boxed Product (Development Kits)
TRF79A6AA21LB000
制造商:Opnext 功能描述:XFP FORM FACTOR - Boxed Product (Development Kits)