PEB2256E INFINEON [Infineon Technologies AG], PEB2256E Datasheet - Page 93

• Manufacturer Part Number: PEB2256E
• Description: E1/T1/J1 Framer and Line Interface Component for Long and Short Haul Applications
• Manufacturer: INFINEON [Infineon Technologies AG]

FALC56 V1.2
PEB 2256
Functional Description E1
The FALC56 also offers the ability to generate and detect a flexible in-band loop-up and
loop-down pattern (LCR1.LLBP = 1). The loop-up and loop-down pattern is individually
programmable from 2 to 8 bits in length (LCR1.LAC1/0 and LCR1.LDC1/0).
Programming of loop codes is done in registers LCR2 and LCR3.
Status and interrupt status bits inform the user whether loop-up or loop-down code has
been detected.
4.3.7
Time Slot 0 Transparent Mode
The transparent modes are useful for loop-backs or for routing data unchanged through
the FALC56.
In receive direction, transparency for ternary or dual-/single-rail unipolar data is always
achieved if the receiver is in the synchronous state. In asynchronous state data is
transparently switched through if bit FMR2.DAIS is set. However, correct time slot
assignment cannot be guaranteed due to missing frame alignment between line and
system side.
Setting of bit LOOP.RTM disconnects control of the internal elastic store from the
receiver. The elastic buffer is now in a “free running” mode without any possibility to
update the time slot assignment to a new frame position in case of resynchronization of
the receiver. Together with FMR2.DAIS this function can be used to realize undisturbed
transparent reception.
Transparency in transmit direction can be achieved by activating the time slot 0
transparent mode (bit XSP.TT0 or TSWM.(7:0)). If XSP.TT0 = 1 all internal information
of the FALC56 (framing, CRC, S
/S
-bit signaling, remote alarm) is ignored. With register
a
i
TSWM the S
-bits, A-bit or the S
-bits can be enabled selectively to send data
i
a
transparently from port XDI to the far end. For complete transparency the internal
signaling controller, idle code generation and AIS alarm generation, single channel and
payload loop-back have to be disabled.
Data Sheet
93
2002-08-27