The TNETA1570 is an asynchronous transfer mode (ATM) segmentation and reassembly (SAR) device with a 64-bit peripheral component interconnect (PCI)-bus interface. This device incorporates ATM adaptation-layer (AAL) processing, ATM SAR processing for full-duplex operation up to STS-3c rate of 155.52 Mbit/s, and the controls for the register interface on the PHY layer. The device provides complete encapsulation and termination of AAL5 packets in hardware. The TNETA1570 supports high-speed networking applications utilizing ATM protocols as either a backbone/backplane or desktop technology. Features include: high level of VPI/VCI support, high-priority segmentation option for constant-bit-rate traffic, early buffer segmentation, buffer scatter/gather capability, and 32-/64-bit PCI-bus support.