Getting Started with PIC
Microcontrollers
Kelly Flowers – NN8E
April 18th, 2011
My Background
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Licensed in 1979
Education – BSEE 1981
Licensed Professional Engineer (Ohio)
Former NOARS member (80’s and 90’s)
Worked for Allen-Bradley/Rockwell for 25yrs
Worked with computers and microprocessors
since 1979
• Began working with PICs in late 90’s
What am I going to cover tonight?
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PIC background, purpose, value proposition
PIC architecture (what’s it look like inside one)
How can you use one?
PIC system overview(dev s/w, programmer, target or
protoboard)
• Programming language choices(Assy, Basic, C)
• Simple examples / hands on
• Recommended resources
Just want to whet your appetite tonight!
The 411 on PICs
• Peripheral Interface Controllers came along in
the 90’s from Microchip
• Small pin count microcontrollers intended to
be ‘smart’ and ‘fast’ I/O front ends for more
traditional microprocessors
• Not intended to have big number-crunching
ability
• Hundreds of PIC’s and dsPIC’s
Why are they so popular?
• Cost!
– Per piece cost is low, typically under $5
– Software development environment needed to program the
devices is FREE (MPLAB IDE)
– Programmers are low cost
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Learning curve is fast(low # of instructions)
Proliferation of hardware, software, books
Backward compatibility
Higher level language compilers(Basic, C)
‘Canned’ serial comms (RS232, SPI, I2C)
Flash memory based, quickly re-programmable
Minimal support parts needed
The simplest of PIC’s
This even has analog input capability!!!
General PIC project overview
INPUTS
Digital
Analog
OUTPUTS
PIC
Digital
SERIAL DEVICES
(displays, EEPROM, RTC, smart sensors)
What do you need to get started?
• PC to load development software(MPLAB) on to
• Programmer which connects between PC and your
PIC
• Target or protoboard or your actual project board to
test your program!
The simplest of PIC projects
Even the 12F675 supports ICSP!
What is MPLAB IDE?
• This is the program you download to your PC to
get started with writing your first program
• Integrated Development Environment
– Free integrated software tool set for developing and
troubleshooting programs for embedded applications
using PIC’s
– Easily integrates with 3rd party software such as high
level language compilers
– Really high quality, professional grade software
• The bad news is Microchip upgrades it a lot and
every few generations changes the look and feel!
Programming Language Choices
• Assembly language is the lowest level
– No extra cost to use
– Fastest
– Manipulating things at the ‘bit level’
– Not easy to do higher level tasks like serial comm
and math
35 Assembly instructions (mid-range)
Two Higher Level Choices
• BASIC
– Micro Engineering Labs
• C
– Multiple vendors (I use CCS)
– Free ‘light’ versions
– Popular with scientists and engineers
• High level languages are used to simplify more complicated
tasks like math and serial communications
• Microchip made using these with MPLAB a breeze!
• Typically execute more slowly than Assembly programs
doing the same thing, but this is not usually a problem
• The full versions cost $100 to $300
You’re gonna need a Programmer…
Putting it all together
• Picture your final project(I like to do the hardware
design first)
• Download MPLAB or install it off supplied disc
• Connect programmer with blank PIC installed
• Launch MPLAB and set up for proper PIC and the
type of programmer you are using
• Write your program(or use an example) and ‘build’
till you have no errors! (the hard part)
• Try it out! Do this as many times as needed since
you can keep erasing and reprogramming in seconds!
I recommend the PICkit 2 + ARRL Book
Project Thoughts….
• Keyer
• Test equipment
– Freq counter
– Signal gen (DC to Daylight with DDS board!!!)
– SWR / power meter
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Repeater control
Automatic control of anything!
Hobby servo control
Any timing and/or counting applications
Holiday lights
Home automation
Resources
• Microchip website
– MPLAB, PICkit 2&3, ICD 2&3, datasheets, app notes
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ARRL “PIC Programming for Beginners”
Hellebuyck “Beginner’s Guide to Embedded C Programming”
Square 1 website(www.sq-1.com)
Wilmshurst “Designing Embedded Systems with PIC Microcontrollers
Nuts and Volts magazine
www.sparkfun.com
– Programmers, proto boards, parts
• www.best-microcontroller-projects.com
– Tutorials, projects
• www.olimex.com
– Excellent cheap proto boards(available at sparkfun)
• www.kangaus.com PIC-EL II proto board, docs
• www.digikey.com, www.mouser.com, www.jameco.com,
www.newark.com PICs and parts
• GOOGLE!!! EBAY!!!