enCoRe™ V CY7C643xx, enCoRe™ V LV CY7C604xx TRM, Document No. 001-32519 Rev *H
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I
I2C
A two-wire serial computer bus by Philips Semiconductors (now NXP Semiconductors). I2C is an
inter-integrated circuit. It is used to connect low-speed peripherals in an embedded system. The
original system was created in the early 1980s as a battery control interface, but it was later used
as a simple internal bus system for building control electronics. I2C uses only two bidirectional
pins, clock and data, both running at +5 V and pulled high with resistors. The bus operates at
100 kbps in standard mode and 400 kbps in fast mode.
ICE
The in-circuit emulator that allows users to test the project in a hardware environment, while
viewing the debugging device activity in a software environment (PSoC Designer™).
idle state
A condition that exists whenever user messages are not being transmitted, but the service is
immediately available for use.
impedance
1. The resistance to the flow of current caused by resistive, capacitive, or inductive devices in a
circuit.
2. The total passive opposition offered to the flow of electric current. Note the impedance is
determined by the particular combination of resistance, inductive reactance, and capacitive
reactance in a given circuit.
input
A point that accepts data in a device, process, or channel.
input/output (I/O)
A device that introduces data into or extracts data from a system.
instruction
An expression that specifies one operation and identifies its operands, if any, in a programming
language such as C or assembly.
integrated circuit (IC)
A device in which components such as resistors, capacitors, diodes, and
are formed
on the surface of a single piece of semiconductor.
interface
The means by which two systems or devices are connected and interact with each other.
interrupt
A suspension of a process, such as the execution of a computer program, caused by an event
external to that process and performed in such a way that the process can be resumed.
interrupt service rou-
tine (ISR)
A block of code that normal code execution is diverted to when the M8C receives a hardware
interrupt. Many interrupt sources may each exist with its own priority and individual ISR code
block. Each ISR code block ends with the RETI instruction, returning the device to the point in
the program where it left normal program execution.
J
jitter
1. A misplacement of the timing of a transition from its ideal position. A typical form of corruption
that occurs on serial data streams.
2. The abrupt and unwanted variations of one or more signal characteristics, such as the inter-
val between successive pulses, the amplitude of successive cycles, or the frequency or
phase of successive cycles.