Maxim Integrated DS33R11 - Manual (Page 12)

DS33R11 Ethernet Mapper with Integrated T1/E1/J1 Transceiver
12 of 344
2.5 Additional HDLC Controllers in the Integrated T1/E1/J1 Transceiver
• Two additional independent HDLC controllers
• Fast load and unload features for FIFOs
• SS7 support for FISU transmit and receive
• Independent 128-byte Rx and Tx buffers with interrupt support
• Access FDL, Sa, or single/multiple DS0 channels
• DS0 access includes Nx64 or Nx56
• Compatible with polled or interrupt driven environments
• Bit-oriented code (BOC) support
2.6 Committed Information Rate (CIR) Controller
• CIR Rate controller limits transmission of data from the Ethernet interface to the serial interface
• CIR granularity at 512kbit/s
• CIR averaging for smoothing traffic peaks
2.7 SDRAM Interface
• Interface for 128Mb, 32-bit-wide SDRAM
• SDRAM Interface speed up to 100MHz
• Auto refresh timing
• Automatic precharge
• Master clock provided to the SDRAM
• No external components required for SDRAM connectivity
2.8 MAC Interface
• MAC port with standard MII (less TX_ER) or RMII
• 10Mbps and 100Mbps Data rates
• Configurable DTE or DCE modes
• Facilitates auto-negotiation by host microprocessor
• Programmable half and full-duplex modes
• Flow control for both half-duplex (back-pressure) and full-duplex (PAUSE) modes
• Programmable Maximum MAC frame size up to 2016 bytes
• Minimum MAC frame size: 64 bytes
• Discards frames greater than programmed maximum MAC frame size and runt, nonoctet bounded, or
bad-FCS frames upon reception
• Configurable for promiscuous broadcast-discard mode.
• Programmable threshold for SDRAM queues to initiate flow control and status indication
• MAC loopback support for transmit data looped to receive data at the MII/RMII interface