PXB4221 Infineon Technologies AG, PXB4221 Datasheet - Page 52

• Manufacturer Part Number: PXB4221
• Description: IWE8 Interworking Element for 8 E1/T1 Lines
• Manufacturer: Infineon Technologies AG

.
Figure 10
No discarding of HEC errored cells as an option is available and selectable via bit
“a_hec_mode” in the register acfg
indicated by setting the most significant bit in the UDF field at the UTOPIA receive
interface.
4.2.1.3
ITU-T I.432.3 [34] recommends the self-synchronizing scrambler x
scrambling at E1 datarates. 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
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
Cell Payload Descrambling
Idle, Physical Layer or Unassigned Cell Deletion
HEC Detection According to ATM Forum
detected
No error
(Chapter
Detection
Mode
52
7.2). In this case an errored HEC is
PXB4219 / PXB4220 / PXB4221
Error detected
Cell discarded
Operational Description
43
+1 for payload
2002-05-06