Datasheet

Emulator User’s Guide for MPLAB X IDE
DS52085A-page 146 2013 Microchip Technology Inc.
Local Label
A local label is one that is defined inside a macro with the LOCAL directive. These
labels are particular to a given instance of a macro’s instantiation. In other words, the
symbols and labels that are declared as local are no longer accessible after the ENDM
macro is encountered.
Logic Probes
Up to 14 logic probes can be connected to some Microchip emulators. The logic probes
provide external trace inputs, trigger output signal, +5V, and a common ground.
Loop-Back Test Board
Used to test the functionality of the MPLAB REAL ICE in-circuit emulator.
LVDS
Low Voltage Differential Signaling. A low noise, low-power, low amplitude method for
high-speed (gigabits per second) data transmission over copper wire.
LVDS differs from normal input/output (I/O) in a few ways:
Normal digital I/O works with 5 volts as a high (binary ‘1’) and 0 volts as a low (binary
0’). When you use a differential, you add a third option (-5 volts), which provides an
extra level with which to encode, and results in a higher maximum data transfer rate.
A higher data transfer rate means fewer wires are required, as in UW (Ultra Wide) and
UW-2/3 SCSI hard disks, which use only 68 wires. These devices require a high trans-
fer rate over short distances. Using standard I/O transfer, SCSI hard drives would
require a lot more than 68 wires.
Low voltage means that the standard 5 volts is replaced by either 3.3 volts or 1.5 volts.
LVDS uses a dual wire system, running 180 degrees of each other. This enables noise
to travel at the same level, which in turn can get filtered more easily and effectively.
With standard I/O signaling, data storage is contingent on the actual voltage level. Volt-
age level can be affected by wire length (longer wires increase resistance, which lowers
voltage). But with LVDS, data storage is distinguished only by positive and negative
voltage values, not the voltage level. Therefore, data can travel over greater lengths of
wire while maintaining a clear and consistent data stream.
Source: http://www.webopedia.com/TERM/L/LVDS.html.
Machine Code
The representation of a computer program that is actually read and interpreted by the
processor. A program in binary machine code consists of a sequence of machine
instructions (possibly interspersed with data). The collection of all possible instructions
for a particular processor is known as its “instruction set”.
Machine Language
A set of instructions for a specific central processing unit, designed to be usable by a
processor without being translated.
Macro
A macro instruction is an instruction that represents a sequence of instructions in
abbreviated form.
Macro Directives
Directives that control the execution and data allocation within macro body definitions.
Makefile
Export to a file the instructions to Make the project. Use this file to Make your project
outside of MPLAB X IDE, i.e., with a make.