Hi, I am about to set the following USB limits: #define USB_BUS_MAX 256 /* units */ #define USB_DEV_MAX 128 /* units */ #define USB_IFACE_MAX 32 /* units */ #define USB_EP_MAX (2*16) /* hardcoded */ #define USB_FIFO_MAX (2 * USB_EP_MAX) The multiplication product of (BUS*DEV*IFACE*FIFO) must fit within a 32-bit unsigned integer. Any objections ? --HPS