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NXP Semiconductors
1. Per default a NFCIP-1 device is in Target mode - meaning its RF field is switched off.
2. The RF level detector is active.
3. Only if it is required by the application the NFCIP-1 device shall switches to Initiator
4. An initiator shall only switch on its RF field if no external RF field is detected by the
5. The initiator performs initialization according to the selected mode.
12.3.2 NFC Configuration
The NFC protocol defines for 106kbps mode an additional Sync-Byte (0xF0 + parity) after
the normal start bit transmitted. As this Sync-Byte has a parity it can be handled by a
host FW as a normal data byte. The PN7462 family however, provides all means to
automatically handle the Sync-Byte.
There are four different areas where adaptations in respect to the default configuration
can be done:
• Reader mode signal processing to remove the Sync-Byte for NFC-Passive-Initiator
• mode
• Card mode signal processing configuration for removal of the Sync-Byte for all other
• NFC-modes (Passive-Target, Active-Target and Initiator)
• Transmitter settings to automatically add the Sync-Byte for transmission
• Adapted CRC preset value to correctly calculate the CRC
12.3.3 Card Mode Detection
The PN7462 family provides the functionality of automatic mode detection for the card
mode. If activated and as soon as the receiver is enabled the signal processing module
does permanently check for an incoming communication at one of the supported
protocols (Type A, B, F). As soon as a Start-of-Frame for one protocol is detected all
reception based CLIF registers are configured automatically to allow reception of the
incoming frame. This includes all Rx protocol framing configuration (data-rate, parity,
CRC, start-/stop-bit, EoF-detection, tx_wait guard time, miller-synchronization).
It is not allowed that FW modifies any of the registers set by the mode-detector while
communication is ongoing. Of course, if necessary setting can be changed later on (e.g.
for changing baudrates). But as all relevant configuration is done by the mode-detector
for the ongoing reception any change made by FW can lead to a fail of the reception.
All transmission related configuration must be set-up by FW. As Type A is the most
timing critical protocol and additionally the activation is done in hardware by the CMA the
default configuration for the mode-detection is Type A.
Consequently, FW needs to set all TX registers according to Type A protocol up-front.
The CRC however needs to be disabled because it is not used for the activation.
UM10858
User manual
COMPANY PUBLIC
mode.
RF Level detector during a time of T
All information provided in this document is subject to legal disclaimers.
Rev. 1.4 — 14 May 2018
.
IDT
314514
UM10858
PN7462 family HW user manual
© NXP B.V. 2018. All rights reserved.
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