DESCRIPTION

The PM7366 FREEDM-8 Frame Engine and Datalink Manager device is a monolithic integrated circuit that implements HDLC processing, and PCI Bus memory management functions for a maximum of 128 bi-directional channels.

FEATURES

• Single-chip Peripheral Component Interconnect (PCI) Bus multi-channel HDLC controller.

• Supports up to 128 bi-directional HDLC channels assigned to a maximum of 8 channelised T1 or E1 links. The number of time-slots assigned to an HDLC channel is programmable from 1 to 24 (for T1) and from 1 to 31 (for E1).

• Supports up to 8 bi-directional HDLC channels each assigned to an unchannelised arbitrary rate link; subject to a maximum aggregate link clock rate of 64 MHz in each direction. Channels assigned to links 0 to 2 can have a clock rate of up 52 MHz when SYSCLK is at 33 MHz. Channels assigned to links 3 to 7 can have a clock rate of up to 10 MHz.

• Supports up to two bi-directional HDLC Channels each assigned to an unchannelised arbitrary rate link of up to 52 MHz when SYSCLK is at 33 MHz.

• Supports a mix of up to 8 channelised and unchannelised links; subject to the constraint of a maximum of 128 channels and a maximum aggregate link clock rate of 64 MHz in each direction.

• For each channel, the HDLC receiver performs 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. The receiver also checks for packet abort sequences, octet aligned packet length and for minimum and maximum packet length.

• Alternatively, for each channel, the receiver supports a transparent mode where each octet is transferred transparently to host memory. For channelised links, the octets are aligned with the receive time-slots.

• For each channel, time-slots are selectable to be in 56 kbits/s format or 64 kbits/s clear channel format.

• For each channel, the HDLC transmitter performs flag sequence generation, bit stuffing, and, optionally, 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.

• Supports two levels of non-preemptive packet priority on each transmit channel. Low priority packets will not begin transmission until all high priority packets are transmitted.

• Alternatively, for each channel, the transmitter supports a transparent mode where each octet is inserted transparently from host memory. For channelised links, the octets are aligned with the transmit time-slots.

• Directly supports a 32-bit, 33 MHz PCI 2.1 interface for configuration, monitoring and transfer of packet data, with an on-chip DMA controller with scatter/gather capabilities.

• Provides 8 kbytes of on-chip memory for partial packet buffering in each direction. This memory can be configured to support a variety of different channel configurations from a single channel with 8 kbytes of buffering to 128 channels, each with a minimum of 48 bytes of buffering.

• Supports PCI burst sizes of up to 128 bytes for transfers of packet data.

• Pin compatible with PM7364 (FREEDM-32) device.

• Provides a standard 5 signal P1149.1 JTAG test port for boundary scan board test purposes.

• Supports 3.3 and 5 Volt PCI signaling environments.

• Low power CMOS technology.

• 256 pin enhanced ball grid array (SBGA) or 272 pin plastic ball grid array (PBGA) packages (27 mm X 27 mm).

APPLICATIONS

• IETF PPP interfaces for routers

• Frame Relay interfaces for ATM or Frame Relay switches and multiplexors

• FUNI or Frame Relay service inter-working interfaces for ATM switches and multiplexors.

• D-channel processing in ISDN terminals and switches.

• Internet/Intranet access equipment.

• Packet-based DSLAM equipment.