peb2256 Infineon Technologies Corporation, peb2256 Datasheet - Page 116

• Manufacturer Part Number: peb2256
• Description: E1/t1/j1 Framer And Line Interface Component For Long And Short Haul Applications
• Manufacturer: Infineon Technologies Corporation

4.6.4
The local loop-back mode selected by LIM0.LL = 1 disconnects the receive lines RL1/2
or RDIP/RDIN from the receiver. Instead of the signals coming from the line the data
provided by the system interface is routed through the analog receiver back to the
system interface. However, the bit stream is transmitted undisturbedly on the line.
However, an AIS to the distant end can be enabled by setting FMR1.XAIS = 1 without
influencing the data looped back to the system interface.
Note that enabling the local loop usually invokes an out-of-frame error until the receiver
resynchronizes to the new framing. The serial codes for transmitter and receiver have to
be identical.
Figure 39
Data Sheet
RL1
RL2
XL1
XL2
Local Loop
Local Loop (E1)
MUX
Clock +
Data
Recovery
AIS-GEN
RCLK
116
Rec.
Framer
Trans.
Framer
Functional Description E1
Elast.
Store
Elast.
Store
FALC56 V1.2
ITS09749
RDO
XDI
PEB 2256
2002-08-27