m24lr16e-r STMicroelectronics, m24lr16e-r Datasheet - Page 64

• Manufacturer Part Number: m24lr16e-r
• Description: 16 Kbit Eeprom With Password Protection, Dual Interface & Energy Harvesting 400 Khz I²c Bus & Iso 15693 Rf Protocol At 13.56 Mhz
• Manufacturer: STMicroelectronics

M24LR16E-R protocol description
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M24LR16E-R protocol description
The transmission protocol (or simply “the protocol”) defines the mechanism used to
exchange instructions and data between the VCD and the M24LR16E-R in both directions.
It is based on the concept of “VCD talks first”.
This means that an M24LR16E-R does not start transmitting unless it has received and
properly decoded an instruction sent by the VCD. The protocol is based on an exchange of:
●
●
Each request and each response are contained in a frame. The frame delimiters (SOF,
EOF) are described in
Each request consists of:
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●
●
●
●
●
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Each response consists of:
●
●
●
●
●
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The protocol is bit-oriented. The number of bits transmitted in a frame is a multiple of eight
(8), that is an integer number of bytes.
A single-byte field is transmitted least significant bit (LSBit) first. A multiple-byte field is
transmitted least significant byte (LSByte) first and each byte is transmitted least significant
bit (LSBit) first.
The setting of the flags indicates the presence of the optional fields. When the flag is set (to
one), the field is present. When the flag is reset (to zero), the field is absent.
Table 23.
Table 24.
Request SOF Request_flags
Response
SOF
a request from the VCD to the M24LR16E-R,
a response from the M24LR16E-R to the VCD.
a request SOF (see
flags,
a command code,
parameters depending on the command,
application data,
a 2-byte CRC,
a request EOF (see
an answer SOF (see
flags,
parameters depending on the command,
application data,
a 2-byte CRC,
an answer EOF (see
Response_flags
VCD request frame format
M24LR16E-R Response frame format
Section
Figure 20
Figure
Figure 35
Figure 41
Doc ID 018932 Rev 7
Parameters
12.
Command
22).
code
and
to
to
Figure
Figure
Figure
Parameters
40),
46).
21),
Data
Data
2-byte CRC
2-byte CRC
M24LR16E
Response
Request
EOF
EOF