PN512_11 Datasheet, PDF (26/125 Pages) NXP Semiconductors – Transmission module Integrated data mode detector

NXP Semiconductors
PN512
Transmission module
9.2.1.8 Status1Reg
Contains status bits of the CRC, Interrupt and FIFO-buffer.
Table 30. Status1Reg register (address 07h); reset value: XXh, X100X01Xb
7
6
5
4
3
2
1
RFFreqOK CRCOk CRCReady IRq TRunning RFOn HiAlert
Access
r
r
r
r
r
r
r
Rights
0
LoAlert
r
Table 31. Description of Status1Reg bits
Bit
Symbol
Description
7
RFFreqOK Indicates if the frequency detected at the RX pin is in the range of
13.56 MHz.
Set to logic 1, if the frequency at the RX pin is in the range
12 MHz < RX pin frequency < 15 MHz.
Note: The value of RFFreqOK is not defined if the external RF
frequency is in the range from 9 to 12 MHz or in the range from
15 to 19 MHz.
6
CRCOk
Set to logic 1, if the CRC Result is zero. For data transmission and
reception the bit CRCOk is undefined (use CRCErr in register
ErrorReg). CRCOk indicates the status of the CRC co-processor,
during calculation the value changes to ZERO, when the calculation is
done correctly, the value changes to ONE.
5
CRCReady Set to logic 1, when the CRC calculation has finished. This bit is only
valid for the CRC co-processor calculation using the command
CalcCRC.
4
IRq
This bit shows, if any interrupt source requests attention (with respect
to the setting of the interrupt enable bits, see register CommIEnReg
and DivIEnReg).
3
TRunning
Set to logic 1, if the PN512’s timer unit is running, e.g. the timer will
decrement the TCounterValReg with the next timer clock.
Note: In the gated mode the bit TRunning is set to logic 1, when the
timer is enabled by the register bits. This bit is not influenced by the
gated signal.
2
RFOn
Set to logic 1, if an external RF field is detected. This bit does not store
the state of the RF field.
1
HiAlert
Set to logic 1, when the number of bytes stored in the FIFO-buffer
fulfills the following equation:
HiAlert = (64 – FIFOLength ) ≤ WaterLevel
Example:
FIFOLength = 60, WaterLevel = 4 → HiAlert = 1
FIFOLength = 59, WaterLevel = 4 → HiAlert = 0
0
LoAlert
Set to logic 1, when the number of bytes stored in the FIFO-buffer
fulfills the following equation: LoAlert = FIFOLength ≤ WaterLevel
Example:
FIFOLength = 4, WaterLevel = 4 → LoAlert = 1
FIFOLength = 5, WaterLevel = 4 → LoAlert = 0
PN512
Product data sheet
COMPANY PUBLIC
All information provided in this document is subject to legal disclaimers.
Rev. 3.7 — 18 May 2011
111337
© NXP B.V. 2011. All rights reserved.
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