DS3181/DS3182/DS3183/DS3184
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3.7 Receive FIFO Features
Storage capacity for four cells or 256 bytes of packet data per port
Programmable port address
Programmable fill level thresholds
Underflow and overflow status indications
3.8 Receive System Interface Features
UTOPIA L2 / UTOPIA L3 interface in cell mode, POS-PHY L2 / POS-PHY L3 or SPI-3 interface in packet or
mixed traffic modes
8, 16, or 32-bit data bus at clock rates from 10 MHz to 66 MHz (52 MHz in L2 modes)
Polled and direct cell available outputs
Controls include enables/disables/settings for: HEC transfer, signal inversions, parity enable/polarity, cell
available deassertion time
3.9 Transmit System Interface Features
UTOPIA L2 / UTOPIA L3 interface in cell mode, POS-PHY L2 / POS-PHY L3 or SPI-3 interface in packet or
mixed traffic modes
8, 16, or 32-bit data bus at clock rates from 10 MHz to 66 MHz (52 MHz in L2 modes)
Polled and direct cell available outputs
Controls include enables/disables/settings for: HEC transfer, signal inversions, parity enable/polarity, cell
available deassertion time
3.10 Transmit FIFO Features
Storage capacity for four cells or 256 bytes of packet data per port
Programmable port address
Programmable fill level thresholds
Underflow and overflow status indications
3.11 Transmit Cell Processor Features
Programmable fill cell type
HEC calculation and insertion/overwrite, including coset addition
Cell scrambling using the self-synchronizing scrambler (x
43+1) for ATM over DS3/E3
Distributed Sample Scrambler (DSS) for clear-channel ATM (cell-based physical layer)
Single-bit and multiple-bit header error insertion for diagnostics
Controls include enables/disables/settings for: cell processing, HEC insertion, coset polynomial addition, cell
scrambling, fill cell type, error insertion type/rate/count, HEC bit corruption
Counter for number of cells read from the transmit FIFO
Cell mapping into the DS3/E3 frame, the PLCP frame, an externally defined frame, or the entire line bandwidth
Octet alignment option for externally defined frame formats
3.12 Transmit Packet Processor Features
FCS calculation (16-bit or 32-bit) and insertion/overwrite
Programmable FCS error insertion for diagnostics
Bit or octet stuffing
Programmable inter-frame fill insertion (flags or all-ones)
Automatic packet abort insertion
Packet scrambling using the self-synchronizing scrambler (x
43+1)
Controls include enables/disables/settings for: packet processing, FCS insertion or overwrite, 16/32-bit FCS,
inter-frame fill type/length, scrambling, FCS error insertion type/rate/count
Counters for number of packets and bytes read from the transmit FIFO
Octet alignment with octet stuffing option for externally defined frame formats