Datasheet

PN512 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2016. All rights reserved.
Product data sheet
COMPANY PUBLIC
Rev. 5.2 — 16 June 2016
111352 102 of 137
NXP Semiconductors
PN512
Full NFC Forum-compliant frontend
The PN512 has to be configured after each power up, before using the automatic
Anticollision/Polling function (AutoColl command). During a hard power down (reset pin)
this configuration remains unchanged.
This command terminates automatically when finished and the active command is idle.
18.3.1.3 Generate RandomID
This command generates a 10-byte random number which is initially stored in the internal
buffer. This then overwrites the 10 bytes in the internal 25-byte buffer. This command
automatically terminates when finished and the PN512 returns to Idle mode.
18.3.1.4 CalcCRC
The FIFO buffer content is transferred to the CRC coprocessor and the CRC calculation is
started. The calculation result is stored in the CRCResultReg register. The CRC
calculation is not limited to a dedicated number of bytes. The calculation is not stopped
when the FIFO buffer is empty during the data stream. The next byte written to the FIFO
buffer is added to the calculation.
The CRC preset value is controlled by the ModeReg register’s CRCPreset[1:0] bits. The
value is loaded in to the CRC coprocessor when the command starts.
This command must be terminated by writing a command to the CommandReg register,
such as, the Idle command.
If the AutoTestReg register’s SelfTest[3:0] bits are set correctly, the PN512 enters Self
Test mode. Starting the CalcCRC command initiates a digital self test. The result of the
self test is written to the FIFO buffer.
18.3.1.5 Transmit
The FIFO buffer content is immediately transmitted after starting this command. Before
transmitting the FIFO buffer content, all relevant registers must be set for data
transmission.
This command automatically terminates when the FIFO buffer is empty. It can be
terminated by another command written to the CommandReg register.
18.3.1.6 NoCmdChange
This command does not influence any running command in the CommandReg register. It
can be used to manipulate any bit except the CommandReg register Command[3:0] bits,
for example, the RcvOff bit or the PowerDown bit.
18.3.1.7 Receive
The PN512 activates the receiver path and waits for a data stream to be received. The
correct settings must be chosen before starting this command.
This command automatically terminates when the data stream ends. This is indicated
either by the end of frame pattern or by the length byte depending on the selected frame
type and speed.
Remark: If the RxModeReg register’s RxMultiple bit is set to logic 1, the Receive
command will not automatically terminate. It must be terminated by starting another
command in the CommandReg register.