MT90222 Datasheet, PDF (64/155 Pages) Zarlink Semiconductor Inc – 4/8/16 Port IMA/TC PHY Device

MT90222/3/4
Data Sheet
5.6 UTOPIA Operation in IMA Mode
In IMA mode, many MT90222/3/4s, with up to eight UTOPIA ports each (one port per IMA Group), can be served by
an external UTOPIA L2 ATM-Layer device provided the UTOPIA limitation of 31 ports in total is observed. This
provides up to 31 different logical IMA-channels. Note that port 31 (1F in hexadecimal format) is reserved.
Pease also refer to Technical Note ZLAN-88: UTOPIA Interface between MT90224/3/2 and Specific ATM
Controllers, as there might be some limitations on maximum number of PHY addresses supported depending on the
type of ATM controller that is interfaced with MT90224/3/2.
5.7 UTOPIA Loopback
With UTOPIA loopback enabled, the Tx UTOPIA port will accept cells and loop these back to the Rx UTOPIA
interface. The Rx UTOPIA interface will then output these cells.The UTOPIA loopback is enabled by setting the bit
9 in UTOPIA Input Control Register (0x0052). With UTOPIA loopback, only one PHY address can be tested at a
time.
5.8 Examples of UTOPIA Operations Modes
Figure 15 shows the connection of one ATM Device to one MT90224.
ATM Layer
ATM
Physical Layer
TxClk
TxEnb*
TxAddr
TxClav
TxData
TxSOC
Rxclk
RxEnb*
RxAddr
RxClav
RxData
RxSOC
Framer
.
MT90224 ^.
.
.
.
Framer
Figure 15 - ATM Interface to MT90224
Figure 16 shows the connection of one ATM Device with more than one MT90224.
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Zarlink Semiconductor Inc.