Specifications
Appendix C I2C Interface Management Installation and Operation Manual
C-4 Management Procedure MiRICi-E3T3 Ver. 2.2
Index: written into addresses 0x80 and 0x81 – The Index bytes determine the
command code of the host message.
Read/Write: written into address 0x82 – This byte determines if the command is
a read or write operation.
Length: written into address 0x83 is the number of bytes the parameter
comprises.
Parameter: written into addresses from 0x84. The parameter length must be
exactly as defined in the Length field. Each I
2
C message will carry up to eight
bytes of management message.
Once the full message is stored, MiRICi-E3T3 reads the message and responds
with the respective read or write operation.
C.3 Management Procedure
The host is defined as the master and MiRICi-E3T3 is the slave, only the host can
start the management communication procedure.
The host accesses addresses 0x80–0x9E, in the same way that it accesses the
SFP identification addresses (0x00–0x5F).
I
2
C messages from the host are composed from read and write messages. In a
read command, the read parameters (Index, R/W, and Length) are stored at
addresses 0x80-0x83. Afterwards, MiRICi-E3T3 receives the required data and
stores it in address 0x84. The complete message is then delivered via I
2
C to the
host.
Read Message
I
2
C encapsulation structure:
• Includes I
2
C Control and Write bits in the first byte.
• Next byte contains 0x80 (as the first address).
• Next byte with the First byte of the Index (MSB).
• Next byte with the Second byte of the Index (LSB).
• Next byte contains 0x01 for a read operation.
• Byte contains 0x01 for the Length.
• MiRICi-E3T3 gets the required data byte and stores it in address 0x84.
To read the required byte, the host sends a new I
2
C message with the following
structure:
• I
2
C Control bits and Read bits in the first byte.
• Next byte contains 0x84 (the address that the parameter is read from).
• The content of address 0x84 is delivered to the host equipment.
In the event that two or more bytes are to be read, two I
2
C messages are
required to read addresses 0x84, 0x85, etc.
Note