參數(shù)資料
型號(hào)： MT90221
廠商： Mitel Networks Corporation
英文描述： 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）)
中文描述： 四IMA的/單向物理層設(shè)備（IMA的四端口/單向物理層設(shè)備（四端口自動(dòng)柜員機(jī)IMA的和單向處理器））
文件頁數(shù)： 19/116頁
文件大?。?/td> 309K
代理商： MT90221
MT90221
11
The remaining 58 cells can be assigned to any of the
12 TX FIFOs. The TX FIFOs are divided in 8 TX
UTOPIA FIFOs and 4 TX Link FIFOs.The MT90221
implements one TX UTOPIA FIFO for each link when
used in UNI and one for each IMA Group for a total of
8 TX UTOPIA FIFOs. Each TX UTOPIA FIFO is
associated with one TX UTOPIA Address. Please
refer to the paragraph 5.0 UTOPIA Interface
Operation for more details.
one common Filler Cell used in IMA mode
one Idle Cell used in UNI mode
In addition, for each link to be used in IMA mode, an
internal TX Link FIFO is utilized. These TX Link
FIFOs are holding the cell streams that are to be
sent on each TX serial port. There is a total of 4 TX
Link FIFOs and their size is programmed on a per
group basis using the
TX IMA Control
register.
When a link is used in UNI mode, its corresponding
TX Link FIFO is disabled and the TX UTOPIA FIFO
is used.
TX UTOPIA FIFO Length Definition
registers are
used to set the TX UTOPIA FIFO size. A maximum of
15 cells can be assigned to any single FIFO. The
size of unused TX UTOPIA FIFOs should be set to
zero. The recommended size for the IMA Group TX
UTOPIA FIFO is 1.
In IMA Mode, the ATM User Cells are first placed in
the IMA TX UTOPIA FIFO and then transferred, by
the internal round robin scheduler, to the proper TX
Link FIFO. The TX UTOPIA FIFO length for each link
configured in IMA mode should be set to zero.
The
TX IMA Control
registers are used to set the
size of the internal TX Link FIFO. An upper and lower
level limit must be set for the internal TX Link FIFO.
In UNI Mode, the ATM User Cells are queued in the
TX UTOPIA FIFO until sent over the T1/E1 link.
The recommended upper limit value for the internal
TX Link FIFO is five and the recommended lower
limit is one when operating in ITC clocking mode.
When operating in CTC mode, the recommended
upper limit value for the internal TX Link FIFO is six
and the recommended lower limit is one. In the case
where CTC mode is used and when the ICP cells on
all the links are sent with the same ICP cell offset
and when carrying a CBR-type traffic, an upper value
of 7 may be required.
2.3
ATM cell octet byte alignment conforms to ITU G.804
recommendations for T1 or E1 framer parallel to
serial format conversion.
The
TX PCM Control
and
RX PCM Control
registers are used to select the T1 or E1 mode of
operation. Refer to Section 4, Description of the
PCM Interface, for more details.
Parallel to Serial PCM Interface
2.4
The MT90221 supports up to four independent IMA
Groups. Each of the four T1/E1 trunks can be
assigned to any one of these IMA Groups. A T1/E1
trunk cannot be assigned to more than one IMA
Group. Refer to Figure 3 for a functional block
diagram of the transmitter.
ATM Transmit Path in IMA Mode
The IMA transmitter splits the incoming stream into N
sub-streams, where 1
≤
N
≤
4. Each sub-stream is
passed to a separate line interface device that
transmits the cells on a physical link.
The physical line rate is either 1.544 Mbps (T1) or
2.048 Mbps (E1). The transmitter inserts so-called
ICP cells in the various outgoing streams according
to the IMA specification. The ICP cells are inserted
every M ATM cells on each link. This is the task of
the scheduler.
2.4.1
The IMA frame length (value of M) can be 256, 128,
64, or 32. The value of M for each IMA Group is set
by the
TX Group Control Mode
registers. M is fixed
once an IMA Group is setup and should remain
unchanged so long as that group is operational.
IMA Frame Length (M)
2.4.2
The
TX ICP Cell Offset
registers control the position
of the ICP cell in the IMA frame for each link. This
parameter should remain unchanged so long as that
group is operational.
Position of the ICP Cell in the IMA Frame
2.4.3
The MT90221 supports both the Common Transmit
Clock (CTC) and Independent Transmit Clock (ITC)
modes of operation. The desired mode is specified
by writing to the
TX Group Control Mode
register. A
reference link must be specified in the
TX Group
Control Mode
register. The MT90221 introduces a
Stuff cell on the reference link every 2048 cells and
determines the appropriate time to insert a Stuff cell
on the remaining group links. See paragraph 2.4.4,
Stuff Cell Rate, for more details.
Transmit Clock Operation
相關(guān)PDF資料
PDF描述
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）)
MT9042B ()
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
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
MT90222AG 制造商:Microsemi Corporation 功能描述:ATM IMA 40MBPS 2.5V 384BGA - Trays
MT90222AG2 制造商:Microsemi Corporation 功能描述:ATM IMA 40MBPS 2.5V 384BGA /BAKE/DRYPACK - Trays
MT90223AG 制造商:Microsemi Corporation 功能描述:ATM IMA 80MBPS 2.5V 384BGA - Trays
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。

采購需求

(若只采購一條型號(hào)，填寫一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠商 批號(hào) 封裝
添加更多采購

我的聯(lián)系方式

*
*
*