An extended Universal-Serial Bus (EUSB) host has reduced loading by using
radio frequency (RF) transceivers or direct wiring traces rather than a
pair of legacy USB cables. The reduced loading opens the eye pattern. The
EUSB device transfers internal data using chained Direct-Memory Access
(DMA). Registers in a DMA controller point to a vector table that has
vector entries, each pointing to a destination and a source. The source
is a memory table for a memory group. The memory table has entries for
several memory segments. Each memory-table entry has a pointer to a
memory segment and a byte count for the segment. Once all bytes in the
segment are transferred, a flag in the entry indicates when another
memory segment follows within the memory group. When an END flag is read,
then vector table is advanced to the next vector entry, and another
memory group of memory segments processed.