Freescale Semiconductor MPC8260 - Manual (Page 1018)

ATM AAL1 Circuit Emulation Service
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
31-2 Freescale Semiconductor
– Segment PDU directly from external memory
– Partially filled cells support (configurable on a per-VC basis)
– Sequence number generation
– Sequence number protection (CRC-3 and even parity) generation
– Pointer generation during segmentation in structure AAL1 cell format
– Clock recovery using external SRTS logic during reassembly in unstructured AAL1
– Statistics gathering on a per-VC basis:
– AAL1 Tx cell count
– AAL1 Tx buffer underrun
• Circuit emulation service (CES)
— ATM to TDM
– Structured and unstructured data are transferred between the ATM and MCC automatically
without CPU intervention
– In case of pre-underrun, the MCC start sending the last frame or the user-defined underrun
template. The MCC and ATM controller automatically perform slip control with no CPU
intervention.
– In case of pre-overrun, the ATM receiver discards incoming cells until the MCC transmitter
empties enough buffers for the receiver to restart.
– Supports common channel signaling (CCS)
– Supports channel associated signaling (CAS)
– Up to 4 (one per trunk) CAS blocks residing in internal RAM when in automatic
CAS mode and up to 8 blocks when in core CAS modify mode
– Supports Nx64 E1/T1 channels
– CAS routing table on per-VC basis
– Automatic un-packing of the CAS information during reassembly and updating
of the internal CAS block
— TDM to ATM
– Structured and unstructured data are automatically transferred between the MCC and ATM
controller without CPU intervention
– Supports common channel signaling (CCS)
– Supports channel associated signaling (CAS)
– Up to 4 (one per trunk) CAS blocks residing in internal RAM when in automatic
CAS mode and up to 8 blocks when in core CAS modify mode
– Support Nx64 E1/T1 channels
– CAS routing table on per-VC basis
– Automatic packing of CAS information from internal RAM to AAL1 Tx cells
– Once per superframe, the CPM fetches the CAS information from an
external
framer and updates each internal CAS block.