mfrc522 NXP Semiconductors, mfrc522 Datasheet - Page 18

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

NXP Semiconductors
112132
Product data sheet
9.2.1.7 ErrorReg
Error bit register showing the error status of the last command executed.
Table 19:
Table 20:
[1]
Bit
7
6
5
4
3
2
1
0
Symbol
Access
Rights
Bit
Command execution will clear all error bits except for bit TempErr. A setting by software is impossible.
Symbol
WrErr
TempErr
-
BufferOvfl
CollErr
CRCErr
ParityErr
ProtocolErr
Description of ErrorReg bits
WrErr
ErrorReg register (address 06h); reset value: 00h
7
r
[1]
TempErr
6
r
Rev. 3.2 — 22 May 2007
Description
Set to logic 1, when data is written into the FIFO by the host during the
MFAuthent command or if data is written into the FIFO by the host
during the time between sending the last bit on the RF interface and
receiving the last bit on the RF interface.
Set to logic 1, if the internal temperature sensor detects overheating.
In this case, the antenna drivers are switched off automatically.
Reserved for future use.
Set to logic 1, if the host or a MFRC522’s internal state machine (e.g.
receiver) tries to write data into the FIFO buffer although the FIFO
buffer is already full.
Set to logic 1, if a bit-collision is detected. It is cleared automatically at
receiver start-up phase. This bit is only valid during the bitwise
anticollision at 106 kbit/s. During communication schemes at 212,
424 and 848 kbit/s this bit is always set to logic 0.
Set to logic 1, if bit RxCRCEn in register RxModeReg is set and the
CRC calculation fails. It is cleared to logic 0 automatically at receiver
start-up phase.
Set to logic 1, if the parity check has failed. It is cleared automatically
at receiver start-up phase. Only valid for ISO/IEC 14443A/MIFARE
communication at 106 kbit/s.
Set to logic 1, if one out of the following cases occur:
•
•
Set to logic 1 if the SOF is incorrect. It is cleared automatically at
receiver start-up phase. The bit is only valid for 106 kbit/s.
During the MFAuthent Command, bit ProtocolErr is set to logic 1,
if the number of bytes received in one data stream is incorrect.
RFU
5
-
BufferOvfl
4
r
CollErr
3
r
CRCErr
2
r
Contactless Reader IC
ParityErr ProtocolErr
MFRC522
© NXP B.V. 2007. All rights reserved.
1
r
18 of 109
0
r
®