mfrc522 NXP Semiconductors, mfrc522 Datasheet - Page 64

• Manufacturer Part Number: mfrc522
• Description: Contactless Reader Ic
• Manufacturer: NXP Semiconductors

NXP Semiconductors
112132
Product data sheet
Fig 21. Overview MFIN/MFOUT Signal Routing
R x Bit Stream
Tx Bit Stream
Digital Part
M FRC522
11.5 CRC co-processor
M anchester
D ecoder
C oder
M iller
Remark: The MFRC522 has an extra supply pin (SVDD and PVSS as Ground line) for the
The following parameters of the CRC co-processor can be configured. The CRC preset
value can either be 0000h, 6363h, A671h or FFFFh depending on the bits CRCPreset in
register ModeReg.
The CRC polynomial for the 16-bit CRC is fixed to x
The register CRCResultReg indicates the result of the CRC calculation. This register is
split into two 8-bit registers indicating the higher and lower byte.
The bit MSBFirst in the register ModeReg indicates that data will be loaded with MSB first.
Table 147: CRC co-processor parameters
Parameter
CRC Register Length
CRC Algorithm
CRC Preset Value
Serial data stream R x
Serial data stream Tx
TestBus
internal
MFIN and MFOUT pads.
If MFIN pin is not used it should be connected to SVDD or PVSS.
If SVDD pin is not used it should be connected to DVDD or PVDD or any other
voltage supply pin.
TS
0
1
R FU
U AR T
Sel
0
1
2
3
4
5
6
7
M FO ut
Sel
0
1
2
3
0
M anchester w sub-carrier
internal
N R Z coding w /o sub-
carrier (> 106 kbps)
D em odulator
Rev. 3.2 — 22 May 2007
Sub-carrier
Value
16 bit CRC
Algorithm according ISO/IEC 14443A and CCITT
0000h, 6363h,A671h or FFFFh depending on the CRCPresetReg
register settings
M FO UT
M FIN
Envelop
TS
1
0
1
2
3
D river
Sel
16
+ x
D em odulator
M odulator
12
Analog Part
M FRC 522
+ x
5
+ 1.
Contactless Reader IC
MFRC522
D river
© NXP B.V. 2007. All rights reserved.
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TX2
TX1
RX