Rainbow Electronics MAX66020 - Manual (Page 12)

Write Single Block
The normal way to write data to the device is through
Write Single Block. This command uses one command-
specific parameter, which is the memory block number.
Valid block numbers are 00h to 11h. Writing a block
takes t
PROG . If this command is processed without any
error, the response information field consists of an indi-
cator byte with the code 00h. The response is transmit-
ted after the memory is updated.
Depending on the protection settings of the memory
location to be updated, the MAX66020 manipulates
data as it arrives in a buffer. Upon receiving a Write
Single Block command for a write-protected location,
e.g., a self-locking nibble or byte in memory block 11h,
the buffer is loaded with the data already in memory,
rather than the data transmitted in the request.
Similarly, if the target memory block is in EPROM mode,
the buffer is loaded with the bitwise logical AND of the
transmitted data and data already in memory. In all
other cases, the data sent by the master arrives in the
buffer unaltered.
Lock Block
This command permanently locks (write protects) the
selected block and reports the success of the operation
in the response. Locking a block takes t
PROG . If this
command is processed without any error, the response
information field consists of an indicator byte with the
code 00h. The response is transmitted after the protec-
tion byte is updated. The block protection can alterna-
tively be achieved by directly writing to memory block
11. Before using the Lock Block command, the final
block data should be defined and written to the device.
Read Single Block
This command allows for retrieving the data of a single
memory block. This command uses one command-spe-
cific parameter, which is the memory block number.
Valid block numbers are 00h to 11h.
MAX66020
ISO/IEC 14443 Type B-Compliant
1Kb Memory Fob
12 ______________________________________________________________________________________
COMMAND BLOCK NUMBER NEW BLOCK DATA
21h (1 Byte) (8 Bytes)
Request Information Field for the Write Single Block Command
Command Block Number
22h (1 Byte)
Request Information Field for the Lock Block Command
COMMAND BLOCK NUMBER
20h (1 Byte)
INDICATOR MEMORY DATA
00h (8 Bytes)
Request Information Field for the Read Single Block Command
Response Information Field for the Read Single Block Command (No Error)