Department of Electronic & Electrical Engineering
Introduction to microcontrollers
A microcontroller is a small computer on a single integrated circuit
containing:
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Processor core (CPU)
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Memory
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Programmable input/output peripherals.
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Program memory
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More . . .
Microcontrollers are designed for embedded applications, in contrast to
the microprocessors used in personal computers or other general purpose
applications.
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Applications
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Car industry
Telephones
Appliances
Cameras
Displays
Gadgets
Remote controls
Washing machine
STUDENT PROJECTS!!!
Department of Electronic & Electrical Engineering
Typical Input and output
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Inputs:
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Switches
Sensors(light,sound,temperature,humidity)
Analogue to digital conversion (ADC)
LEDs
Outputs
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LCD (displays)
DAC (audio signals)
Control / Power Electronics
Department of Electronic & Electrical Engineering
PIC microcontroller
Made by
Microchip Technology
Peripheral Interface Controller
We will be using the PIC16F84A.
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Simple ( 35 instructions RISC )
Cheap ( ~ £3 )
Robust (I haven't broken one yet!!!)
Department of Electronic & Electrical Engineering
Background reading
• The Quintessential PIC (quite advanced)
• Many simpler online articles on PIC
programing.
• Tutorials/links via moodle.
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Example: Voltmeter Demo
Parallel interface
Serial digital 12bits (SPI)
LCD display
ADC
3.142 Volts
PIC
Voltage(analogue)
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PIC 16F84A pin layout
Department of Electronic & Electrical Engineering
Summary of pins
OSC1/CLKIN
: Oscillator crystal input.
OSC2/CLKOUT : Oscillator crystal output.
MCLR(inv)
: Master clear(reset)input. Programming voltage input.
RA0 - RA3
RA4/T0CKI
RB0/INT
RB1 - RB7
: Bi-directional I/O port.
: Bi-directional I/O port. Clock input to the TMR0 timer.
: Bi-directional I/O port. External interrupt pin.
: Bi-directional I/O port.
VSS
VDD
: Ground
: Positive supply(+2.0V to +5.5V)
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PIC development.
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Reset
Program/run
CLOCK
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Department of Electronic & Electrical Engineering
Department of Electronic & Electrical Engineering
LAB INTRO DEMO
Simple example program to light up LED maybe a switch?