pxb4219 Infineon Technologies Corporation, pxb4219 Datasheet - Page 47

• Manufacturer Part Number: pxb4219
• Description: Iwe8 Interworking Element For 8 E1/t1 Lines
• Manufacturer: Infineon Technologies Corporation

octet 1
octet 2
octet 3
octet 4
octet 5
octet 6
.
octet 53
• If idle cell insertion according to ITU-T I.361 or ITU-T I.432.1 is desired, the
• If unassigned cell insertion at the NNI or uncontrolled UNI according to ITU-T I.361 is
The payload of idle or unassigned cells consists of the same octet which is repeated 48
times. It is programmable by the “prg_tx_pl” field of the “txid” register.
• For ITU-T I.432.1 compliant idle cells, the “prg_tx_pl” field of “txid” should be set to
• The pre-assigned values of the information field of all unassigned cells are for further
4.1.1.4
ITU-T I.432.3 [34] recommends the self-synchronizing scrambler x
scrambling at E1 datarates. For T1 no scrambling is recommended.
The scrambler function is implemented in the device. It can be disabled per port by the
x43_scrambling bit in the “ATM Transmit Reference Slot” in RAM2.
4.1.1.5
The HEC generation is implemented according to ITU-T I.432.1 [33] using the generator
polynomial x
the case of bit-slips it is recommended that
• the check bits are added (modulo 2) to an 8-bit pattern (coset) before being inserted
• the recommended pattern is “0101 0101".
Data Sheet
“prg_tx_hd” field of “txid” should be set to 0000_0001
desired, the “prg_tx_hd” field of “txid” should be set to 0000 XXX0. For X any value is
allowed.
0110_1010
study (ITU-T I.361 [30])
in the last octet of the header.
GFC[3:0]/VPI[11:8] = prg_tx_hd[7:4]
Cell Payload Scrambling
HEC Generation
8
B
+ x
.
2
+ x + 1. To significantly improve the cell delineation performance in
VPI[3:0] = 0000
VCI[3:0] = 0000
VCI[11:4] = 0000_0000
B
B
prg_tx_pl[7:0]
prg_tx_pl[7:0]
47
UDF
.
PTI[2:0] = prg_tx_hd[3:1]
PXB4219 / PXB4220 / PXB4221
B
.
VCI[15:12] = 0000
VPI[7:4] = 0000
B
Operational Description
43
+1 for payload
B
B
2002-05-06
prg_tx_
CLP =
hd[0]