mfrc531 NXP Semiconductors, mfrc531 Datasheet - Page 9

• Manufacturer Part Number: mfrc531
• Description: Iso/iec 14443 Reader Ic
• Manufacturer: NXP Semiconductors

NXP Semiconductors
MFRC531_34
Product data sheet
PUBLIC
Fig 4.
Connection to microprocessor: common read and write strobes
address bus (A3 to An)
address bus (A0 to A2)
data bus (D0 to D7)
HIGH
Data strobe (NDS)
Read/Write (R/NW)
9.1.3.2 Common read and write strobe
9.1.3.3 Common read and write strobe: EPP with handshake
9.1.4 Serial Peripheral Interface
Refer to
Refer to
Remark: In the EPP standard, a chip select signal is not defined. To cover this situation,
the status of the NCS pin can be used to inhibit the nDStrb signal. If this inhibitor is not
used, it is mandatory that pin NCS is connected to pin DVSS.
Remark: After each Power-On or Hard reset, the nWait signal on pin A0 is
high-impedance. nWait is defined as the first negative edge applied to the nAStrb pin after
the reset phase. The MFRC531 does not support the Read Address Cycle.
The MFRC531 provides compatibility with the 5-wire Serial Peripheral Interface (SPI)
standard and acts as a slave during SPI communication. The SPI clock signal SCK must
be generated by the master. Data communication from the master to the slave uses the
MOSI line. The MISO line sends data from the MFRC531 to the master.
Fig 5.
DECODER
ADDRESS
Section 13.4.2 on page 94
Section 13.4.3 on page 95
Connection to microprocessor: EPP common read/write strobes and handshake
NCS
A0 to A2
D0 to D7
ALE
NRD
NWR
MFRC531
Rev. 3.4 — 26 January 2010
multiplexed address/data (AD1 to AD8)
Address strobe (nAStrb)
Data strobe (nDStrb)
Read/Write (nWrite)
LOW
HIGH
HIGH
nWait
056634
for timing specification.
for timing specification.
non-multiplexed address
LOW
HIGH
LOW
multiplexed address/data (AD0 to AD7)
Address strobe (AS)
Data strobe (NDS)
Read/Write (R/NW)
NCS
A2
A1
A0
AD0 to AD7
ALE
NRD
NWR
MFRC531
DECODER
ADDRESS
001aal222
ISO/IEC 14443 reader IC
NCS
A2
A1
A0
AD0 to AD7
ALE
NRD
NWR
MFRC531
MFRC531
© NXP B.V. 2010. All rights reserved.
001aal221
9 of 116