cn8236 Mindspeed Technologies, cn8236 Datasheet - Page 125

• Manufacturer Part Number: cn8236
• Description: Atm Servicesar Plus With Xbr Traffic Management
• Manufacturer: Mindspeed Technologies

CN8236
ATM ServiceSAR Plus with xBR Traffic Management
28236-DSH-001-B
Additional EOM/SSM
5.3.2.5 AAL3/4 MIB
5.3.2.4 AAL3/4
Processing
Counters
Upon termination of a CPCS-PDU, the CN8236 performs the following
additional checks and functions on each EOM or SSM cell received:
Whenever an AAL3/4 MIB counter rolls over to all 0s, the CN8236 writes a RSM
status queue entry with the CNT_ROVR bit set to a logic high, and the
HEAD_VCC_INDEX field pointing to the AAL3/4 Head VCC entry which
contains the rolled-over counter. This processing step takes place for the
CRC10_ERR, MID_ERR, LI_ERR, SN_ERR, BOM_SSM_ERR, and
EOM_ERR counters.
• The Length field in the CPCS-PDU trailer is written to the
• The CN8236 performs a PAD length check to see if the sum of all LIs for
• The CN8236 performs a Modulo 32 bit check. If the sum of all LIs for the
• If the Alignment (AL) field in the CPCS-PDU trailer is not all 0s, it sets
• If the BTAG field in the RSM VCC table entry does not match the ETAG
• The CN8236 checks the BAT_EN bit in the AAL3/4 Head VCC table
• The CN8236 writes the AAL3/4 CPCS-PDU trailer to the data buffer.
CPCS_LENGTH field of a RSM status queue entry written for the VCC.
the CPCS-PDU – LENGTH – 8 = [0 to 3] octets. If in error, it sets the
PAD_ERROR bit in the status queue entry.
CPCS-PDU is not modulo 32 bit, the SAR sets the MOD_ERROR bit in
the status queue entry.
the AL_ERROR bit in the status queue entry.
field in the CPCS-PDU trailer, it sets the TAG_ERROR bit in the status
queue entry.
entry. If BAT_EN is high, it compares the BASIZE field to the Length
field in the CPCS-PDU trailer. If not a match, it sets the BA_ERROR bit in
the status queue entry. If BAT_EN is low, it checks if the Length field is
> BASIZE; and if so, sets the BA_ERROR bit in the status queue entry.
Mindspeed Technologies
™
5.0 Reassembly Coprocessor
5.3 CPCS-PDU Processing
5-15