PIC Micro Controller C Routine Library

• Input / Output

• Math / Functions / Conversions

• Conditionals / Program flow

• Time / Clocks / Delays

• Memory / Tables / Data

Note: This library is entirely built by people just like you who have decided to share what they have written... please consider placing the code that you are proud of on these pages (see the login link below) and, if you use code from this site, it might be good to say thanks to and credit the author.

Most of the C code in this section is for Hi-Tech C and the FREE! MPLAB compatible PICC-Lite which is essentially the same, but supports only the 16x84 devices. It may be possible to use these routines in other C compilers.

Notes:

• Use defines to improve code readability
  
  #define _TRIS(pin) pin(_TRIS_F)
  #define _TRIS_F(alpha,bit) (TRIS ## alpha ## bit)
  #define _PORT(pin) pin(_PORT_F)
  #define _PORT_F(alpha,bit) (R ## alpha ## bit)
  #define _LAT(pin) pin(_LAT_F)
  #define _LAT_F(alpha,bit) (LAT ## alpha ## bit)
  #define _WPU(pin) pin(_WPU_F)
  #define _WPU_F(alpha,bit) (WPU ## alpha ## bit)
   
  #define pinSwitch(f) f(A,2) //Switch, INPUT , pin RA2
  #define pinLed(f) f(B,5) //Led, OUTPUT , pin RB5
   
  _TRIS(pinSwitch) = 1; //make pin an input
  _WPU(pinSwitch) = 1; // turn on internal pull-up
  _TRIS(pinLed) = 0; // make pin an output
   
  while(1){
    _PORT(pinLed) = ! _PORT(pinSwitch)
    }
  
  
• In Microchip C compilers (C18, C30 etc.) you can set bits easily:
  #define LED1 LATBbits.RB0
  
  LED1 = 0;
  LED1 = 1;
  

  Andy Kunz says:

  As for working in C, you can probably do 99% of what you need to do in standard C code. Time-critical stuff should be in assembly (to prevent optimization problems), and compiler-specific stuff can be done with include files. (see "defs.h"). I use this all the time to test stuff on a PC, then drop it into the PIC and I can fully expect it will work "first time."

C/C++@

Books:

• Embedded Systems Building Blocks : Complete and Ready-To-Use Modules in C by Jean J. Labrosse Great section on fixed point math.

See also:

• http://www.loginway.com/project_site.htm PIC C programming, the CCS C routines, sample code, libraries and examples.
• bit twiddleing effeciently in c
• http://www.keyghost.com/htpic/Hi-Tech_C_FAQ.htm an independant FAQ for Hitech C
• http://www.phanderson.com/PIC/PICC/index.html PIC C Routines book / disk $49. Recommended.
• http://www.eagleairaust.com.au/sampcode.htm
• http://www.bluebird-electronics.co.uk/books.html is the only PIC C book I've seen so far.
• http://www.fored.co.uk/LearnCFED.htm is a good downloadable beginners' tutorial that is PIC specific. As a C newcomer I found this one the most user-friendly and encouraging source.
• http://www.workingtex.com/htpic PIC micro and C FAQ, sample code, discussions, and more. Enjoy!

Questions:

• robert6717@sbcglobal.net asks: " Hi, I know nothing about programing, where do start and what is the easye to learn??? I have the malab-icd module and the education board???????????" James Newton of James Newton's Massmind replies: I'm not aware of any totally "C-centric" learning material for the PIC's... If you find any, let us know. The standard starting point for learning the PIC (which is not all that easy) is http://www.piclist.com/techref/piclist/begin.htm

• the_ace_place(at)onvol(dot)net asks:

  ACE is an interpreter (A C Emulator) which runs on the PIC family of microprocessors. The language is a subset of ANSI C and thus all programs can be compiled and run using any ANSI C compiler, the IO of the microprocessor being simulated by a special include file. The version for the PIC 16F84 provides 8 programmable IO ports plus one input port. Two of the programmable ports can be configured to provide standard RC servo outputs.
  
  Anyone out there wanting to be a (serious) beta tester?

• "

Interested:

Code:

Comments:

• pic@danlhenry.com

  The list of devices (with only one device, I suppose it's not really a list) that PICC-Lite supports is woefully out of date.

  Microcontroller  Limitations
  ---------------  --------------------------------
  All Baselines    No Limitations
  12F629           No Limitations
  12F675           No Limitations
  16C84            No Limitations
  16F627           2 RAM banks supported
  16F627A          2 RAM banks supported
  16F684           1 RAM banks, 1K program memory supported
  16F690           2 RAM banks, 2K program memory supported
  16F84A           No Limitations
  16F877           2 RAM banks, 2K program memory supported
  16F877A          2 RAM banks, 2K program memory supported
  16F887           2 RAM banks, 2K program memory supported
  16F917           2 RAM banks, 2K program memory supported
  

• pic@danlhenry.com

  Regarding the notes on this page:
  
  http://www.piclist.com/techref/microchip/language/c/index.htm
  
  There is absolutely no reason to resort to the following (which is wrong anyway due to its lacking the 'volatile' qualifier):
  
  #define PIN(x,y,z) static bit x @ ((unsigned)&y*8+z)
  
  HI-TECH already provides definitions for PIC SFRs and SFR bits. It's much more straight forward and less error prone to simply use:
  
  #define LED1 RA0

See: