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PM7344 参数 Datasheet PDF下载

PM7344图片预览
型号: PM7344
PDF下载: 下载PDF文件 查看货源
内容描述: SATURN QUAD T1 / E1 MULTI -PHY用户网络接口设备 [SATURN QUAD T1/E1 MULTI-PHY USER NETWORK INTERFACE DEVICE]
分类和应用: 网络接口
文件页数/大小: 293 页 / 1101 K
品牌: PMC [ PMC-SIERRA, INC ]
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PM7344 S/UNI-MPH  
DATA SHEET  
PMC-950449  
ISSUE 6  
MULTI-PHY USER NETWORK INTERFACE  
9.3  
T1/E1 Framer (FRMR)  
The framing function is provided by the FRMR block. This block searches for the  
framing bit position in the incoming data stream. It searches for the framing bit  
pattern for the following T1 frame formats: SF, and ESF. When searching for  
frame, the FRMR examines each of the 193 (SF), or each of the 4*193 (ESF)  
framing bit candidates. For the E1 frame format, the FRMR searches for frame  
alignment and CRC multiframe alignment in the incoming stream.  
The time required to find frame alignment to an error-free PCM stream  
containing randomly distributed channel data (i.e. each bit in the channel data  
has a 50% probability of being 1 or 0) is dependent upon the framing format. For  
SF, the FRMR determines frame alignment within 4.4ms, 99 times out of 100.  
For ESF the FRMR determines frame alignment within 15ms, 99 times out of  
100. For E1 formatted signals, the FRMR determines frame alignment within  
1ms, 99 times out of 100.  
When the FRMR has found T1 frame alignment, the incoming data is  
continuously monitored for framing bit errors, CRC-6 error events (ESF only),  
and severe errored framing events. The FRMR also detects loss of frame,  
based on a selectable ratio of framing bit errors.  
When the FRMR has found E1 frame alignment, the incoming data is monitored  
for frame alignment signal bit errors. Upon detecting CRC multiframe alignment,  
the FRMR monitors the incoming data for CRC multiframe alignment pattern  
errors, and CRC-4 errors. The FRMR also detects loss of frame, and loss of  
CRC multiframe, based on user-selectable criteria.  
The FRMR extracts the yellow alarm signal bits in T1-SF and T1-ESF framing  
formats. The FRMR extracts and debounces the remote alarm indication signal  
in the E1 framing format.  
9.4  
Alarm Integrator (ALMI)  
The Alarm Integration function is provided by the ALMI block. This block detects  
the presence of T1 yellow, red, and AIS Carrier Fail Alarms (CFA) in SF and ESF  
formats. The block also detects the presence of E1 red CFA and AIS CFA. The  
alarm detection and integration is compatible with the specifications defined in  
ANSI T1.403-1989, TR-TSY-000191, and Q.516.  
For T1 formats, the ALMI block declares the presence of yellow CFA when the  
yellow pattern has been received for 425 ms (± 50 ms); the yellow CFA is  
removed when the yellow pattern has been absent for 425 ms (± 50 ms). The  
presence of red CFA is declared when an out-of-frame condition has been  
present for 2.55 sec (± 40 ms); the red CFA is removed when the out-of-frame  
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE  
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