mt90224 Zarlink Semiconductor, mt90224 Datasheet - Page 45

• Manufacturer Part Number: mt90224
• Description: 8-port Ima/tc Phy Device
• Manufacturer: Zarlink Semiconductor

Incoming ICP cells are automatically detected by the ICP Processing block. As soon as one valid ICP cell is received,
the IMA Frame State Machine moves to the IMA PRESYNC state. When Gamma-valid ICP cells are received, the
state machine moves to the IMA SYNC state. In the IMA PRESYNC state, one errored or missing ICP cell causes
the state machine to return to the IMA HUNT state. In the IMA SYNC state, the state machine transitions to the IMA
HUNT state by any of the following events:
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After the received information is validated, the IMA Group is configured by writing to the RX Reference Link
Control (0x0209 - 0x0210), the RX Link Control (0x00C0-0x00C7) and RX Recombiner (0x0201 - 0x0208)
registers.
Bits 3 and 2 of the RX State (0x00E4) register report the IMA Frame State Machine state for a selected link. When
in IMA HUNT mode, the information required to perform the verification is extracted from the ICP cells received.
The IMA Frame State Machine Status (0x00E5) indicates whether a link’s IFSM is in a Synchronized State. Each
link has one corresponding bit in this register.
3.2.3
All required link information for verification and link validation is extracted from the received ICP cells. The IMA ID,
Link ID (LID), Reference Link Number, ICP Cell Offset and Frame Length can be read and validated before enabling
an IMA Group link. Software obtains this information by writing to the RX Load Values (0x00DC) register to select
a link and then reading the RX Link IMA ID (0x00DE), RX ICP Cell Offset (0x00DF) and RX State (0x00E4)
registers. This information can also be obtained by collecting all the received ICP cells in the RX ICP Cell Buffer and
then processing the contents of the ICP cell (i.e., writing to the RX Cell Type RAM (0x0100 and 0x0101) register
and then reading from the RX ICP cell buffer).
The contents of the link information registers should be read and validated after enabling the RX TDM link in the RX
Link Control (0x00C0-0x00C7) register and before enabling the IMA mode. The link information can be accessed
when a link is either in TC or IMA mode (but will not be updated in IMA mode).
3.2.4
The RX OAM Label is treated differently than the other link’s parameters. Four User Defined OAM Label
(0x00CC-0x00CF) registers (1 register per 2 RX IMA Groups) are used to defined the RX OAM Label. Its value is
written by the software and can be changed at any point in time. However, the RX OAM Label has to match the value
contained in the RX ICP cell for the IMA Frame State Machine to reach the ACTIVE state.
3.2.5
Status bits in the RX OIF Status (0x00D9) register, one bit per link, report OIF conditions. The status bit latches an
OIF condition which corresponds to a transition of the IFSM from SYNC to HUNT. The OIF condition is reported as
a status bit only and cannot generate an interrupt. The status bit is cleared by writing a 0 to the corresponding bit.
There are 16 OIF counters, one per link. For each OIF transition, the 8-bit counter associated with the link is
incremented by one. The counter can be read with indirect access when issuing a load command with the RX Load
Values (0x00DC) register. The counter can be cleared by writing to the RX OIF Counter Clear Command (0x00DA)
register.
one missing ICP cell
Alpha consecutive invalid ICP cells
Beta consecutive errored ICP cells
Link Information
RX OAM Label
Out of IMA Frame (OIF) Condition
Zarlink Semiconductor Inc.
MT90222/3/4
45
Data Sheet