參數(shù)資料
型號(hào): MT90220
廠商: Mitel Networks Corporation
英文描述: Octal IMA/UNI PHY Device(八端口 IMA/UNI 物理層設(shè)備(八端口ATM IMA和UNI處理器))
中文描述: 八路IMA的/單向物理層設(shè)備(八端口IMA的/單向物理層設(shè)備(八端口自動(dòng)柜員機(jī)IMA的和單向處理器))
文件頁數(shù): 26/118頁
文件大小: 310K
代理商: MT90220
MT90220
18
3.3.1.2
All
information is extracted from the ICP received 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
register to select a link and by reading
the
RX Link IMA ID
,
RX Link ICP Offset
,
RX Link
ID and Reference
and
RX State
registers. This
information can also be obtained by collecting all the
received ICP cells in the RX ICP Cell Buffer and then
processing the content of the ICP cell (i.e., writing to
the
RX ICP Cell Type RAM
register and then
reading from the RX ICP cell buffer).
Link Information
required
verification
and
link
validation
The contents of the link information registers should
be read after enabling the RX PCM link in the
RX
PCM Link Control
register and before enabling the
IMA mode. The link information can be accessed
when a link is either in UNI or IMA mode.
3.3.1.3
The RX OAM Label is treated differently than the
other link’s parameters. Four registers, the
RX OAM
Label
registers, 1 per RX IMA Group, 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.
RX OAM Label
3.3.2
Status bits in the
RX OIF Status
register, one bit per
link, is reporting OIF conditions. The status bit is
latching 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.
Out of IMA Frame (OIF) Condition
There are 8 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
register. The counter can be
cleared by writing to the
RX OIF Counter Clear
Command
register.
3.3.3
Link Out Of IMA Frame (LIF)
Synchronization
A link is declared out of IMA Frame (LIF)
synchronization state when the IFSM goes in HUNT
mode for ’gamma +2’ frames after it was in SYNC
state. This condition is latched in bit 2 of the
IRQ
Link Status
register. Refer to 6.2.2 IRQ Link Status
and IRQ Link Enable Registers for more details.
The LIF status bit is reporting the current condition of
the IMA Frame State Machine at the time it is read
and cannot not be programmed to generate an
interrupt when exiting the LIF condition. The
software has to poll the LIF status bit to determine
when the condition is cleared.
3.3.4
The MT90220 scans each incoming cell received for
the Filler Cell Indication code. Filler cells are written
to external RAM to keep the IMA frame aligned. They
are automatically discarded after being read from the
external RAM by the recombiner.
Filler Cell Handling
3.3.5
Each incoming ICP cell received is scanned for the
Stuff Indication Code. Stuff cells are inserted at the
transmit end as two identical and consecutive ICP
cells with the Link Stuff Indication Bits set as defined
in the IMA specification. The MT90220 automatically
discards one of the two Stuff cells without storing it in
external RAM. The other is kept and processed as a
regular ICP cell. IMA Frame synchronization is
maintained for all cases (except case 7, O-19
optional requirements) as described in Figure 20 of
the IMA Specification.
Stuff Cell Handling
3.3.6
An internal buffer is implemented to collect cells from
the RX PCM links for analysis by the software. This
storage unit is a circular buffer for each link and
contains up to three cells per link. The buffer can
selectively collect:
all valid cells coming on a RX PCM port
all valid ICP cells
all valid ICP cells which contain new
information (as indicated by the SCCI field,
valid only when the link is in IMA mode).
The type of cells collected is defined in the
RX ICP
Cell Type RAM
registers. A status bit and a
maskable IRQ alerts the software when a new cell is
waiting for processing in a specific link. These are
found in the
IRQ Link Status
and
Enable
registers.
Valid ICP cells when a link is in UNI mode is
determined by a valid HEC byte. When in IMA mode,
a valid ICP cell must meet the criteria defined in
Table 16 of the ATM IMA spec.
Received ICP Cell Buffer
Software can directly access the cells in the RX
buffer through a two-cell-wide access window. This
access window can be advanced, one cell at a time,
by issuing a command to move the internal pointer to
the next cells. Since the window accesses two cells,
相關(guān)PDF資料
PDF描述
MT90221 Quad IMA/UNI PHY Device(四端口 IMA/UNI 物理層設(shè)備(四端口ATM IMA和UNI處理器))
MT90401 SONET/SDH System Synchronizer(SONET/SDH 系統(tǒng)同步裝置(由一個(gè)數(shù)字鎖相環(huán)組成))
MT9040 T1/E1 Synchronizer(T1/E1 系統(tǒng)同步裝置(由一個(gè)數(shù)字鎖相環(huán)組成))
MT9041A ()
MT9041B T1/E1 System Synchronizer(T1/E1系統(tǒng)同步裝置(由一個(gè)數(shù)字鎖相環(huán)組成))
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MT90220AL 制造商:Zarlink Semiconductor Inc 功能描述:I.C.
MT90220ALX01 制造商:Mitel Networks Corporation 功能描述:
MT90221 制造商:MITEL 制造商全稱:Mitel Networks Corporation 功能描述:Quad IMA/UNI PHY Device
MT90221AL 制造商:MITEL 制造商全稱:Mitel Networks Corporation 功能描述:Quad IMA/UNI PHY Device
MT90222 制造商:ZARLINK 制造商全稱:Zarlink Semiconductor Inc 功能描述:4/8/16 Port IMA/TC PHY Device