mfrc531 NXP Semiconductors, mfrc531 Datasheet - Page 85

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

NXP Semiconductors
MFRC531_34
Product data sheet
PUBLIC
Fig 19. EEPROM programming timing diagram
command active
programming
EEPROM
E2Ready
WriteE2
TxIRq
NWR
data
11.3.1.2 Timing diagram
11.3.1.3 WriteE2 command error flags
write
E2
addr
LSB
Figure 19
Assuming that the MFRC531 finds and reads byte 0 before the microprocessor is able to
write byte 1 (t
(t
microprocessor stores byte 1 to byte 4 in the FIFO buffer.
If the EEPROM start byte address is 16Ch then byte 0 is stored at that address. The
MFRC531 copies the subsequent data bytes into the EEPROM input buffer. Whilst
copying byte 3, it detects that this data byte has to be programmed at the EEPROM byte
address 16Fh. As this is the end of the memory block, the MFRC531 automatically starts
a programming cycle.
Next, byte 4 is programmed at the EEPROM byte address 170h. As this is the last data
byte, the E2Ready and TxIRq flags are set indicating the end of the EEPROM
programming activity.
Although all data has been programmed into the E2PROM, the MFRC531 stays in the
WriteE2 command. Writing more data to the FIFO buffer would lead to another EEPROM
programming cycle continuing from EEPROM byte address 171h. The command is
stopped using the Idle command.
Programming is restricted for EEPROM block 0 (EEPROM byte address 00h to 0Fh). If
you program these addresses, the AccessErr flag is set and a programming cycle is not
started.
Addresses above 1FFh are taken modulo 200h; see
EEPROM memory organization.
MSB
addr
prog
byte 0
), which takes approximately 5.8 ms to complete. In the meantime, the
byte 1
shows programming five bytes into the EEPROM.
t
prog,del
prog,del
programming byte 0
byte 2
t
prog
= 300 ns). This causes the MFRC531 to start the programming cycle
byte 3
Rev. 3.4 — 26 January 2010
byte 4
056634
byte 1, byte 2 and byte 3
programming
t
prog
Section 9.2 on page 12
programming byte 4
ISO/IEC 14443 reader IC
t
prog
MFRC531
© NXP B.V. 2010. All rights reserved.
for the
command
001aak623
Idle
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