The ISP1581 is a cost-optimized and feature-optimized Universal Serial Bus (USB) interface device, which fully complies with the Universal Serial Bus Specification Rev. 2.0. It provides high-speed USB communication capacity to systems based on a microcontroller or microprocessor. The ISP1581 communicates with the system's microcontroller/processor through a high-speed general-purpose parallel interface. The ISP1581 supports automatic detection of USB 2.0 system operation. The USB 1.1 fall-back mode allows the device to remain operational under full-speed conditions. It is designed as a generic USB interface device so that it can fit into all existing device classes, such as: Imaging Class, Mass Storage Devices, Communication Devices, Printing Devices and Human Interface Devices. The internal generic DMA block allows easy integration into data streaming applications. In addition, the various configurations of the DMA block are tailored for mass storage applications.