OVERVIEW
The FREEDM-32P256 chip offers the following features:
• Single-chip multi-channel HDLC controller with a 66 MHz, 32-bit Peripheral Component Interconnect (PCI) 2.1 compatible bus for configuration, monitoring, and transfer of packet data.
• An on-chip DMA controller with scatter/gather capabilities.
• Supports up to 256 bi-directional HDLC channels assigned to a maximum of 32 channelized T1/J1/E1 links. You can program the number of time-slots assigned to an HDLC channel from 1 to 24 (for T1/J1) and from 1 to 31 (for E1).
• Supports up to 256 bi-directional HDLC channels assigned to a maximum of 32 MVIP digital telephony buses at 2.048 Mbit/s per link, or 8 H-MVIP buses at 8.192 Mbit/s per link.
• Supports up to 32 bi-directional HDLC channels, each assigned to an unchannelized arbitrary-rate link, subject to a maximum aggregate link clock-rate of 64 MHz in each direction.
• Channels assigned to links 0 to 2 support clock rates up to 52 MHz. Channels assigned to links 3 to 31 support clock rates up to 10 MHz. In the special case where no more than 3 high-speed links are used, the maximum aggregate link clock-rate is 156 MHz.
• Links configured for channelized T1/J1/E1 or unchannelized operation support the gapped-clock method for determining time-slots, which is backwards compatible with the FREEDM-8 and FREEDM-32 devices.
• For each channel, the HDLC receiver supports programmable flag-sequence detection, bit de-stuffing and frame-check sequence validation. The receiver supports the validation of both CRC-CCITT and CRC-32 frame-check sequences.
• For each channel, the HDLC transmitter supports programmable flag-sequence generation, bit stuffing and frame-check sequence generation. The transmitter supports the generation of both CRC-CCITT and CRC-32 frame-check sequences. The transmitter also aborts packets under the direction of the host or automatically when the channel underflows.
• Provides 32 kbytes of on-chip memory for partial packet buffering in both the transmit and receive directions. You can configure this memory to support a variety of different channel configurations: from a single channel with 32 kbytes of buffering, to 256 channels, each with a minimum of 48 bytes of buffering.
• Provides a standard five signal P1149.1 JTAG test-port for boundary scan board-test purposes.
• Supports 5 Volt tolerant I/Os for non-PCI signals. Supports a 3.3 Volt PCI signaling environment.
• 329-pin plastic ball grid-array (PBGA) package.

APPLICATIONS
• IETF PPP interfaces for routers.
• Frame Relay interfaces for ATM or Frame Relay switches and multiplexers.
• FUNI or Frame Relay service interworking interfaces for ATM switches and multiplexers.
• Internet/Intranet access equipment.
• Packet-based DSLAM equipment.