Specifications

Installation and Operation Manual Appendix C I2C Interface Management
MiTOP-E1/T1 Ver. 1.0 Management Procedure C-3
The host message structure may be a write message such as a configuration
message or a read message like status. Messages are sent to MiTOP-E1/T1 in the
format shown as described in
Figure
C-3.
Index
2 bytes
Read/Write
1 byte
Length of Parameter
1 byte
Data
Reserved Area
128 0x80
0xFF
255
Figure
C-3. Message Format
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, MiTOP-E1/T1 reads the message and responds
with the respective read or write operation.
C.3 Management Procedure
The host is defined as the master and MiTOP-E1/T1 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, MiTOP-E1/T1 receives the required data and
stores it in address 0x84. The complete message is then delivered via I
2
C to the
host.