mt90226ag ETC-unknow, mt90226ag Datasheet - Page 32

• Manufacturer Part Number: mt90226ag
• Description: 16/8 Port Tc Phy Device
• Manufacturer: ETC-unknow

32
4.2.1
Two links in a pair are OR’ed together by using this mode. The links that are paired are pre-determined: link 0 is
paired with link 1, link 2 is paired with link 3 and so on. When link 0 and link 1 are paired, the pins associated with
link 1 cannot be used and are tri-stated, however, bit 7 of its TDM TX(RX) Link Control registers must be set. The
two links operate using the Clock and SYNC signals of link 0. The same logic applies for the other pairs.
This mode is selected in TDM TX Link Control (0x0600-0x060F) and TDM RX Link Control (0x0700-0x070F) by
the following settings. Note that both links in a pair must have the same settings.
4.2.2
Four links in a group are OR’ed together by using this mode. The links that are grouped are pre-determined: links
0, 1, 2 and 3 are grouped and the OR’ed input/output is available on link 0 only. Pins associated with links 1, 2 and
3 cannot be used and are tri-stated, however, bit 7 of TDM TX(RX) Link Control registers for those three links must
be set. The four links operate using the Clock and SYNC signal of link 0. The same logic applies for the other groups.
This mode is selected in TDM TX Link Control (0x0600-0x060F) and TDM RX Link Control (0x0700-0x070F) by
the following settings. Note that all four links in a group must have the same settings.
4.3
A multiplex mode is offered by many multi-channel T1/E1 framers to multiplex several T1/E1 links on to one high
speed data link. The same mode is available on MT90225/226, where two or four 2.048 Mb/s links are multiplexed
using a common clock of 8.192 or 16.384 MHz. In this major mode, two or four links running at 2.048 bps (either
2.048MHz Single mode or 4.096MHz Single mode) are interleaved on a time slot basis (byte by byte) to provide a
multiplexed link at a data rate of 4.096 Mb/s or 8.192 Mb/s.
In Multiplex mode, links are treated or processed the same way as they are in Single mode. The only difference is
the way that data is carried on TDM bus. In Single mode, each link uses its own TDM port to carry data, whereas in
Multiplex mode two or four links shares a single high speed port. As in Wire-OR mode, links in Multiplex mode must
be configured in the same as they were in Single mode, except for TDM Link Control registers.
When multiplexed mode is used, the time slots on the multiplexed links have to use a common synchronized clock
source and Frame Pulse for the multiplexed links. Multiplexing of fractional T1/E1 is also possible through the control
of merged mapping registers.
Only ST-BUS mode is supported in Multiplex mode.
There are two minor modes in Multiplex mode, 2-link multiplexing and 4-link multiplexing.
Data rate (bits 6:5) = 00 or 01
Multiplex mode (bits 4:3) = 01
Clock and Sync format (bit 2) = 0 or 1
Enable (bit 7) = 1
Cell delineation mode (bit 10 of TDM RX Link Control only) = 0
Data rate (bits 6:5) = 00 or 01
Multiplex mode (bits 4:3) = 10
Clock and Sync format (bit 2) = 0 or 1
Enable (bit 7) = 1
Cell delineation mode (bit 10 of TDM RX Link Control only) = 0
Wire-OR mode - 2 link grouping
Wire-OR mode - 4 link grouping
Multiplex mode
Zarlink Semiconductor Inc.
Data Sheet