Rainbow Electronics MAX66020 - Manual (Page 5)

Block 10h provides storage for user-programmable
parameters that are defined by the ISO/IEC 14443 stan-
dard. These are application data field and AFI. The
remaining bytes (U1, U2, U3) are not defined by the
communication standard; the application software can
use them, e.g., for proprietary markings. Block 11h con-
tains control bytes that determine the operation of the
individual pages (EPROM-emulation mode, write protec-
tion of individual blocks), or to write protect the applica-
tion data field, the AFI, and U1. The S-Lock byte, if
programmed to a suitable code, only protects itself from
future changes. The self-protection feature can be used
to permanently mark the fob as being “special,” as defined by the application. Table 1 illustrates the rela-
tionship between the controlling register in block 11h
and the memory area affected. Tables 2 and 3 specify
the code assignments to achieve the protection.
Besides the storage for 8 data bytes, each memory
block has 2 integrity bytes, which are not memory
mapped. The integrity bytes function as a MAX66020-
m a i n t a i n e d , 1 6 - b i t w r i t e - c y c l e c o u n t e r . H a v i n g
reached its maximum value of 65,535, the write-cycle
counter stops incrementing, but does not prevent
additional write cycles to the memory block. The
integrity bytes can be read through the Custom Read
Block command.
MAX66020
ISO/IEC 14443 Type B-Compliant
1Kb Memory Fob
_______________________________________________________________________________________ 5
DATA BYTE NUMBER
(SEQUENCE LEFT TO RIGHT AS WRITTEN TO OR READ FROM DEVICE)
INTEGRITY BYTES BLOCK
NUMBER
0 1 2 3 4 5 6 7 LSB MSB
00h Page 0 User EEPROM R/(W) Write-Cycle Counter
01h Page 0 User EEPROM R/(W) Write-Cycle Counter
02h Page 0 User EEPROM R/(W) Write-Cycle Counter
03h Page 0 User EEPROM R/(W) Write-Cycle Counter
04h Page 1 User EEPROM R/(W) Write-Cycle Counter
05h Page 1 User EEPROM R/(W) Write-Cycle Counter
06h Page 1 User EEPROM R/(W) Write-Cycle Counter
07h Page 1 User EEPROM R/(W) Write-Cycle Counter
08h Page 2 User EEPROM R/(W) Write-Cycle Counter
09h Page 2 User EEPROM R/(W) Write-Cycle Counter
0Ah Page 2 User EEPROM R/(W) Write-Cycle Counter
0Bh Page 2 User EEPROM R/(W) Write-Cycle Counter
0Ch Page 3 User EEPROM R/(W) Write-Cycle Counter
0Dh Page 3 User EEPROM R/(W) Write-Cycle Counter
0Eh Page 3 User EEPROM R/(W) Write-Cycle Counter
0Fh Page 3 User EEPROM R/(W) Write-Cycle Counter
10h ISO/IEC 14443 Application Data Field AFI U1 U2 U3 Write-Cycle Counter
11h BP1 BP2 BP3 BP4 ADF-Lock AFI-Lock U1-Lock S-Lock Write-Cycle Counter
Figure 4. Memory Map