User manual

DynamixUM‐SNBUserManualVer1.0095
Framing is required to recover the channelised E1. In transparent operation, the framing is configured as Unframed. In this
case the G.SHDSL framer must be set to Nx64 with N=32. For any framing such as FAS or CAS, the G.SHDSL framer must be
set to E1, then the E1 framing here may be set accordingly.
Channel Framing
PCM31 FAS
PCM31C FAS+CRC4
PCM30 FAS+CAS
PCM30C FAS+CAS+CRC4
FULL Unframed
FAS Frame Alignment Signal uses a 7-bits pattern to establish and maintain the frame
synchronization. The FAS word is located in timeslot 0 of frame. In FAS mode there are
1~31 timeslot available for use data.
CAS Also known as time slot 16 multi-framing. It requires a multi-framing alignment signal to
be present for frame sync. The Multi-frame Alignment Signal (MFAS) is inserted into the
16th timeslot of frame 0 of the 16-frame multi-frame.
In CAS mode, there are 30 channels available for user data. If timeslot 16 is included in
the unit’s mapping, it will be disregarded.
FAS
01234 16
31
Time Slots
64k 64k 64k 64k 64k 64k 64k896k
17 ~ 30
CAS
5 ~ 15
704k
Data Rate (x) 960kbps Data Rate (y) 960kbps
Maximun Data Rate = x + y = 1920kbps
CRC4 The CRC-4 checksum bits are transmitted in the outgoing E1 data stream. Also the
received signal is checked for errors.
CRC-4 checksum cannot be sent in unframed mode.
Unframed In this mode, user data is inserted into all 32 channels (64k x 32 = 2048k) of the E1
stream. The object of running without framing is to utilize the full bandwidth of the E1 line.