mfrc522 NXP Semiconductors, mfrc522 Datasheet - Page 22

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

NXP Semiconductors
112132
Product data sheet
9.2.1.13 ControlReg
Table 30:
Miscellaneous control bits.
Table 31:
Table 32:
Bit
7 to 6
5 to 0
Bit
7
6
5 to 3
2 to 0
Symbol TStopNow TStartNow
Access
Rights
Bit
Symbol
TStopNow
TStartNow
-
RxLastBits
Symbol
-
WaterLevel
Description of WaterLevelReg bits
ControlReg register (address 0Ch); reset value: 10h
Description of ControlReg bits
w
7
Rev. 3.2 — 22 May 2007
Description
Reserved for future use.
This register defines a warning level to indicate a FIFO-buffer over- or
underflow:
Remark: For the calculation of HiAlert and LoAlert see
w
6
Description
Set to logic 1, the timer stops immediately.
Reading this bit will always return 0.
Set to logic 1 starts the timer immediately.
Reading this bit will always return 0.
Reserved for future use.
Shows the number of valid bits in the last received byte. If 0, the
whole byte is valid.
The bit HiAlert in Status1Reg is set to logic 1, if the remaining
number of bytes in the FIFO-buffer space is equal or less than the
defined number of WaterLevel bytes.
The bit LoAlert in Status1Reg is set to logic 1, if equal or less than
WaterLevel bytes are in the FIFO.
“Status1Reg”.
5
RFU
4
-
3
2
Contactless Reader IC
MFRC522
RxLastBits
© NXP B.V. 2007. All rights reserved.
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Section 9.2.1.8
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