Product data

MFRC631 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2014. All rights reserved.
Product data sheet
COMPANY PUBLIC
Rev. 3.3 — 4 February 2014
227433 83 of 120
NXP Semiconductors
MFRC631
High performance ISO/IEC 14443 A/B reader solution
Remark: User defined CRC preset values can be configured by EEprom (see
Section 8.7.2.1
, Table 28 “Configuration area (Page 0)”).
9.9.2 RxCrcCon
Table 130. TxCrcPreset bits
Bit Symbol Description
7RFU -
6 to 4 TXPresetVal Specifies the CRC preset value for transmission (see Table 131
).
3 to 2 TxCRCtype Defines which type of CRC (CRC8/CRC16/CRC5) is calculated:
• 00h -- CRC5
• 01h -- CRC8
• 02h -- CRC16
• 03h -- RFU
1 TxCRCInvert if set, the resulting CRC is inverted and attached to the data frame
(ISO/IEC 3309)
0 TxCRCEn if set, a CRC is appended to the data stream
Table 131. Transmitter CRC preset value configuration
TXPresetVal[6...4] CRC16 CRC8 CRC5
0h 0000h 00h 00h
1h 6363h 12h 12h
2h A671h BFh -
3h FFFEh FDh -
4h---
5h---
6h User defined User defined User defined
7h FFFFh FFh 1Fh
Table 132. RxCrcCon register (address 2Dh)
Bit 7 6 5 4 3 2 1 0
Symbol RxForceCRCWrite RXPresetVal RXCRCtype RxCRCInvert RxCRCEn
Access
rights
r/w r/w r/w r/w r/w
Table 133. RxCrcCon bits
Bit Symbol Description
7 RxForceCrc
Write
If set, the received CRC byte(s) are copied to the FIFO.
If cleared CRC Bytes are only checked, but not copied to the FIFO.
This bit has to be always set in case of a not byte aligned CRC (e.g.
ISO/IEC 18000-3 mode 3/ EPC Class-1HF)
6 to 4 RXPresetVal Defines the CRC preset value (Hex.) for transmission. (see Table 134
).