This document introduces a PCMCIA interface product that is fully compatible with PCMCIA Release 2.1 and PC Card ATA Release 1.02 specifications. It supports fast ATA host-to-buffer burst transfer rates up to 20MB/sec, with automatic sensing of PCMCIA or ATA host interface. The product features integrated PCMCIA attribute memory, PCMCIA card configuration register support, polarity control for host reset signal, PCMCIA twin card support, PCMCIA based ATA address decode support, and emulation of the IBM task file for PC/AT. It also provides a flash memory interface with support for read/write/erase operations, up to 32MB or 64MB capacity, flash memory power down or write protect control, flash memory ready/busy status detection, inverted data bus control, and optional storage of firmware in flash memory array with shadow ROM control.