mfrc531 NXP Semiconductors, mfrc531 Datasheet - Page 84

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

NXP Semiconductors
MFRC531_34
Product data sheet
PUBLIC
11.3.1.1 Programming process
11.3.1 WriteE2 command 01h
11.3 EEPROM commands
Table 139. WriteE2 command 01h
The WriteE2 command interprets the first two bytes in the FIFO buffer as the EEPROM
start byte address. Any further bytes are interpreted as data bytes and are programmed
into the EEPROM, starting from the given EEPROM start byte address. This command
does not return any data.
The WriteE2 command can only be started by the microprocessor. It will not stop
automatically but has to be stopped explicitly by the microprocessor by issuing the Idle
command.
Up to 16 bytes can be programmed into the EEPROM during a single programming cycle.
The time needed is approximately 5.8 ms.
The state machine copies all the prepared data bytes to the FIFO buffer and then to the
EEPROM input buffer. The internal EEPROM input buffer is 16 bytes long which is equal
to the block size of the EEPROM. A programming cycle is started if the last position of the
EEPROM input buffer is written or if the last byte of the FIFO buffer has been read.
The E2Ready flag remains logic 0 when there are unprocessed bytes in the FIFO buffer or
the EEPROM programming cycle is still in progress. When all the data from the FIFO
buffer are programmed into the EEPROM, the E2Ready flag is set to logic 1. Together
with the rising edge of E2Ready, the TxIRq interrupt request flag shows logic 1. This can
be used to generate an interrupt when programming of all data is finished.
Remark: During the E2PROM programming indicated by E2Ready = logic 0, the WriteE2
command cannot be stopped using any other command.
Once E2Ready = logic 1, the WriteE2 command can be stopped by the microprocessor by
sending the Idle command.
Command
WriteE2
Value Action
01h
get data from FIFO buffer and write it
to the EEPROM
Rev. 3.4 — 26 January 2010
056634
FIFO
Arguments and
data
start address LSB
start address MSB
data byte stream
ISO/IEC 14443 reader IC
MFRC531
© NXP B.V. 2010. All rights reserved.
Returned
data
-
-
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