Platform Cable USB attaches to the USB port on a desktop or laptop PC with an off-the-shelf Hi-Speed USB A-B cable. It derives all operating power from the hub port controller. No external power supply is required. A sustained slaveserial FPGA configuration transfer rate of 24 Mb/s is possible in a Hi-Speed USB environment. Actual transfer rates can vary if bandwidth of the hub is being shared with other USB peripheral devices. Device configuration and programming operations using Platform Cable USB are supported by iMPACT download software using Boundary-Scan (IEEE 1149.1 / IEEE 1532), slave-serial mode, or serial peripheral interface (SPI). Platform Cable USB supports indirect (via an FPGA IEEE 1149.1 [JTAG] port) programming of select flash memories including the Platform Flash XL configuration and storage device. Target clock speeds are selectable from 750 kHz to 24 MHz. Platform Cable USB attaches to target systems using a 14-conductor ribbon cable designed for high-bandwidth data transfers. An optional adapter that allows attachment of a flying lead set is included for backward compatibility with target systems that do not use the ribbon cable connector.