beautypg.com

Imux command protocol – Maxim Integrated DS33Z41 User Manual

Page 34

background image

DS33Z41 Quad IMUX Ethernet Mapper

34 of 167

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.