Intel PXA270, Optimization Manual

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Intel® PXA27x Processor Family Optimization Guide Glossary-7
I-Mode A Japanese wireless service for transferring packet-based data to handheld devices created by NTT
DoCoMo. I-Mode is based on a compact version of HTML and does not currently use WAP.
I-cache Instruction cache
IBIS I/O Buffer Information Specification is a behavioral description of the I/O buffers and package characteristics
of a semiconductor device. IBIS models use a standard format to make it easier to import data into circuit
simulation software packages.
iDEN
Integrated Digital Enhanced Network. A technology that allows users to access phone calls, two-way radio
transmissions, paging and data transmissions from one wireless device. iDEN was developed by Motorola and
based on TDMA.
Interrupt Request (IRQ) A hardware signal that allows a device to request attention from a host. The host
typically invokes an interrupt service routine to handle the condition that caused the request.
Interrupt Transfer One of the four USB transfer types. Interrupt transfer characteristics are small data,
non-periodic, low-frequency, and bounded-latency. Interrupt transfers are typically used to handle service needs.
See also transfer type.
I/O Request Packet An identifiable request by a software client to move data between itself (on the host) and an
endpoint of a device in an appropriate direction.
IrDA Infrared Development Association
IRP See I/O Request Packet.
IRQ See Interrupt Request.
ISI Inter-signal interference. Data ghosting caused when multi-path delay causes previous symbols to interfere with
the one currently being processed.
ISM Industrial, Scientific, and Medical band. Part of the wireless spectrum that is less regulated, such as 802.11.
Isochronous Data A stream of data whose timing is implied by its delivery rate.
Isochronous Device An entity with isochronous endpoints, as defined in the USB Specification, that sources or
sinks sampled analog streams or synchronous data streams.
Isochronous Sink Endpoint An endpoint that is capable of consuming an isochronous data stream that is sent by
the host.
Isochronous Source Endpoint An endpoint that is capable of producing an isochronous data stream and sending it
to the host.
Isochronous Transfer One of the four USB transfer types. Isochronous transfers are used when working with
isochronous data. Isochronous transfers provide periodic, continuous communication between host and device. See
also transfer type.
Jitter A tendency toward lack of synchronization caused by mechanical or electrical changes. More specifically,
the phase shift of digital pulses over a transmission medium.
kb/s Transmission rate expressed in kilobits per second. A measurement of bandwidth in the U.S.
kB/s Transmission rate expressed in kilobytes per second.