sri4k STMicroelectronics, sri4k Datasheet - Page 34

• Manufacturer Part Number: sri4k
• Description: 13.56 Mhz Short-range Contactless Memory Chip With 4096-bit Eeprom And Anticollision Functions
• Manufacturer: STMicroelectronics

SRI4K commands
8.7
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READ_BLOCK(Addr) command
Command Code = 08h
On receiving the READ_BLOCK command, the SRI4K reads the desired block and returns
the 4 data Bytes contained in the block. Data Bytes are transmitted with the Least
Significant Byte first and each byte is transmitted with the least significant bit first.
The address byte gives access to the 128 blocks of the SRI4K (addresses 0 to 127).
READ_BLOCK commands issued with a block address above 127 will not be interpreted
and the SRI4K will not return any response, except for the System area located at address
255.
The SRI4K must have received a SELECT() command and be switched to SELECTED state
before any READ_BLOCK() command can be accepted. All READ_BLOCK() commands
sent to the SRI4K before a SELECT() command is issued are ignored.
Figure 41. READ_BLOCK request format
Request parameter:
Figure 42. READ_BLOCK response format
Response parameters:
Figure 43. read_block frame exchange between reader and SRI4K
Reader
SRI4K
–
–
–
–
–
SOF
SOF
S
O
F
ADDRESS: block addresses from 0 to 127, or 255
DATA 1: Less significant data Byte
DATA 2: Data Byte
DATA 3: Data Byte
DATA 4: Most significant data Byte
08h
DATA 1
8 bIts
READ_BLOCK
ADDR
08h
CRC L CRC H
DATA 2
8 bIts
ADDRESS
8 bIts
E
O
F
DATA 3
8 bIts
<-t 0 -><-t 1 ->
S
O
F
DATA 4
8 bits
8 bIts
CRC L
DATA
1
DATA
2
CRC L
8 bits
DATA
3
CRC H
8 bits
DATA
4
CRC H
CRC L CRC H
8 bIts
EOF
AI07684
AI10890b
AI07685
SRI4K
EOF
O
E
F