UDMA/66 <Ultra ATA/66>

Alias:
UATA/66, ATA-66, Fast ATA-2, Ultra DMA/66 and DMA-66
Field:
Personal computer > I/O > IDE/ATA > UDMA/66

Extended specification of IDE (ATA) standard which the Quantum corporation and the Intel corporation announced in 1998, connect the personal computer and the storage unit of the hard disk and the like. Also “Ultra DMA/66” “Fast ATA-2” and so on is called. Transfer rate being maximum, has reached the two times the 66.6MB/s and Ultra ATA. The connector has used the same 40 pin connectors until recently, but the signal conductor has become with 80 of times. Downward compatibility is guaranteed, can connect also the hard disk of Ultra ATA specification and EIDE specification. By the way the formal calling with “Ultra DMA Mode 4”, is standardized formally as a portion of the ATA-5 standard of ANSI.

UDO <Ultra-Density Optical>

Reading: U D o
Field:
Storage > optical disk > UDO

The bulk optical disk which SONY has researched, improves MO. What records maximum 40GB to the disk of 5.25 inches is made possible. Last standard is made to decide to around 2001 2nd quarter, commercialization to 2002 end of year is designated as goal. We adopt phase change recording type, postscript type and rewriting type are prepared.

UDP

Reading: U D tweet
Full spelling: User Datagram Protocol
Field:
Network technology > TCP/IP > UDP

With Internet, also TCP is used as a protocol of transport layer, but as for UDP as for transfer rate it is high, but reliability is low, as for TCP as for reliability is high but transfer rate is low.

UFD <USB memory>

Alias:
USB flash memory, USB flash memory and USB flash drive, USB flash drive and USB memory
Field:
Mobile > memory card > UFD

Connecting to the USB connector, you use, it carries about, possible flash memory. With 32MB - 256MB, it substitutes capacity to the floppy disk, it is being observed easily as the media.

Specification in order originally, you call to the standard of USB “USB Mass Storage Class,” to recognize the hard disk and the like as removable drive has entered. The majority of USB memories is conformed to this USB Mass Storage Class, because the driver for Mass Storage Class which OS side has can be used that way, with relatively new OS does not install the driver and just inserts also the [te] can use USB memory directly

UHCI

Reading: U h sea eye
Full spelling: Universal Host Controller Interface
Field:
Personal computer > I/O > serial /USB > USB > UHCI

One of types of USB controller which controls the communication of the peripheral device and the computer itself of USB connection. UHCI system and OHCI (Open Host Controller Interface) there are 2 types of system in the USB controller, control method and the driver etc differ.

UHCI the Intel corporation directing, with the USB standard which is decided, is loaded onto the chip set of the Intel corporation and the VIA corporation. Simple of interface empty cost is not required, but the load which falls on the computer itself becoming large is difficult point.

Presently, as for the bender which sells the USB equipment from the fact that the driver where the majority corresponds to the both of UHCI and OHCI is offered, as for the user as for the necessity to designate the difference of both excessively as the air it is not.