User`s guide

What is MPLAB
®
IDE?
© 2006 Microchip Technology Inc. DS51519B-page 11
The peripherals and the amount of memory an application needs to run a program
largely determines which PICmicro MCU to use. Other factors might include the power
consumed by the microcontroller and its “form factor,” i.e., the size and characteristics
of the physical package that must reside on the target design.
FIGURE 1-2: Example PICmicro
®
MCU DEVICE PACKAGE
1.1.4 Implementing an Embedded System Design with MPLAB IDE
A development system for embedded controllers is a system of programs running on a
desktop PC to help write, edit, debug and program code – the intelligence of embedded
systems applications – into a microcontroller. MPLAB IDE runs on a PC and contains
all the components needed to design and deploy embedded systems applications.
The typical tasks for developing an embedded controller application are:
1. Create the high level design. From the features and performance desired, decide
which PICmicro MCU or dsPIC DSC device is best suited to the application, then
design the associated hardware circuitry. After determining which peripherals
and pins control the hardware, write the firmware – the software that will control
the hardware aspects of the embedded application. A language tool such as an
assembler, which is directly translatable into machine code, or a compiler that
allows a more natural language for creating programs, should be used to write
and edit code. Assemblers and compilers help make the code understandable,
allowing function labels to identify code routines with variables that have names
associated with their use, and with constructs that help organize the code in a
maintainable structure.
FIGURE 1-3: PICmicro
®
MCU DATA SHEET – TIMING (EXCERPT)
c
2
1
n
DD1
B
p
#leads=n1
E1
E
A2
A1
A
L
CH x 45
°
β
φ
α
(F)
Q3Q2Q1Q4Q3Q2
OSC1
Internal
SCS
(OSCCON<0>)
Program
PC + 2PC
Q1
T1OSI
Q4 Q1
PC + 4
Q1
T SCS
Clock
Counter
System
Q2 Q3 Q4 Q1
T DLY
T T 1 P
T OSC
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