PXB4219E Datasheet, PDF (49/290 Pages) Infineon Technologies AG – Interworking Element for 8 E1/T1 Lines

IWE8, V3.4
PXB 4219E, PXB 4220E, PXB 4221E
Operational Description
.
No error
detected
Detection
Mode
Error detected
Cell discarded
Figure 10 HEC Detection According to ATM Forum
Atmfhec
No discarding of HEC errored cells as an option is available and selectable via bit
“a_hec_mode” in the register acfg (Chapter 7.2). In this case an errored HEC is
indicated by setting the most significant bit in the UDF field at the UTOPIA receive
interface. For correct operation bit P_CELL_DIS must be cleared.
4.2.1.3 Cell Payload Descrambling
ITU-T I.432.3 [34] recommends the self-synchronizing scrambler x⁴³+1 for payload
scrambling at E1 data rates. For T1 no scrambling is recommended.
The self-synchronizing scrambler function is implemented in the device. It can be
disabled per port by the x43_descrambling bit in the “ATM Receive Reference Slot” in
RAM1.
4.2.1.4 Idle, Physical Layer or Unassigned Cell Deletion
According to ITU-T I.361 [30], idle cells, physical layer OAM cells and cells reserved for
use by the physical layer are not passed to the ATM layer at the UNI.
Data Sheet
49
2003-01-20