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DS33Z41 Quad IMUX Ethernet Mapper
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8.9.2 IMUX
Command
Protocol
The format for all commands sent and received in Channel 2 of the IBO Serial Interface is shown in
Figure 8-5
.
The MSB for all commands is a “1”. The next 6 bits contain the actual opcode for the command. The LSB is the
even parity calculation for the byte. These commands will be sent and received on Channel 2 of each of the
T1/E1 interleaved IBO data. The commands that are possible are outlined in
Table 8-3
. Note that the 4 portions of
the IMUX link are separate and the Channel 2 for each link will send and receive commands specific to that link.
The microprocessor can disable links that are not to be aggregated.
Figure 8-5. Command Structure for IMUX Function
"1"
Command
Even
Parity
M
S
B
L
S
B
Table 8-3. Commands Sent and Received on the IMUX Links
COMMAND
NAME
COMMAND BYTE
(P IS EVEN
PARITY)
TRANSMIT/
RECEIVE
COMMENTS
Link Start
1000 001P
Tx or Rx
Initiate the link. The receiver will then search for 3
consecutive sequence numbers.
Sequence
1sss 010P
Tx or Rx
“sss” contains the frame sequence number for
packet segmentation and reassembly.
Rsync
1000 011P
Tx or Rx
This command is sent to indicate to the distant
node that link synchronization has been achieved.
OOF
1000 100P
Tx or Rx
The transmitting device has detected an out of
frame condition.
Nop
1111 111P
Tx or Rx
No operation.