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#define _VERSION_ "V0.0.2"
/************************************************** **********************
* phase84.c
*
* Simple Phase control using PIC16F84 - 100% C Program.
* Using even time slicing method for both Triac and IGBT Drive methods.
* Just change specific #define to choose which method is in use.
*
* Output pin for phase ctrl is RA0
* Zero Cross input is RB0
* Remainder of PORTB is used for level setting 0 to 255 in incs of 2
*
* Output is Active LOW - i.e. it is desigend to pull an LEDs Cathode in an
* opto-coupler low to turn the output ON.
*
* Output Driver Types:
* Either TRIAC or IGBT control can be used with this software by selecting
* the appropiate #define command.
*
* IGBT Driver:
* An IGBT driver turns the output ON at the zero cross point and turns
* the output OFF part way through the cycle - this has really low
* EMI properties and is one of the few methods allowed for phase control
* in European countrys (i.e complies with EN55015 EMI standard).
* Other countries are following suit for example New Zealand and Austrailia
* are almost there (See AS/NZS 4051 and CISPR15 EMI Standards )
* This method of dimming is audibly quiet, does not require extra filter
* componets (If designed properly).It also has a better lamp life and can
* control a wider range of lamps than the TRIAC method of dimming.
*
* TRIAC Driver:
* A TRIAC driver turns the output OFF at the zero-cross and turns the
* output ON part way through the cycle - this has high EMI output and needs
* filter inducors etc. This has been the most popular method of phase
* control since it was first demonstraited in London in 1962. To make
* the TRIAC dimmer complient with modern EMI standards it requires
* carefully designed filter circuits using large Toroid Inductors
* and mains voltage AC rated capacitors.
* This is still the simplest method to do, and quite cheap, but not
* recommended for comercial designs any more.
* It also has a tendancy to reduce Lamp life, and creates alot of audiable
* noise in both the inductors and lamps.
*
*
*
* Processor: PIC16F84 @ 10Mhz
*
* Author: Michael Pearce
*
* Copyright 2001 Michael Pearce
* All Rights Reserved
*
* Free to use for non-comercial, non-profit personal use only.
* For Commercial use please contact author (He doesnt Bite) at
*
* mimemike@paradise.net.nz or mike@lightneasy.com
*
* Started: 10 July 2001 (My 20 something Birthday)
*
************************************************** ***********************
* Version Information
************************************************** ***********************
* Version 0.0.1 - 10 July 2001
* Changed Port Pins to match the circuit diagram.
* Made Input type selectable by #define (Switches or 8bit mode)
* UNTESTED!!!
* 98 Words ROM (IGBT Output + Switch Input Version)
* 99 Words ROM (IGBT Output + 8bit Input Version)
* 91 Words ROM (TRIAC Output + Switch Input Version)
* 92 Words ROM (TRIAC Ouptut + 8 bit Input Version)
************************************************** ***********************
* Version 0.0.1 - 10 July 2001
* Change User Input to an up and DOWN Key on 10ms Interrupt
* Test as Functional
* 98 Words ROM
************************************************** ***********************
* Version 0.0.0 - 10 July 2001
* First Draft of the Project
* Tested as functional
* 79 words of ROM
************************************************** ***********************/
#include <pic.h>
#define ON 0 /* To set Output to ON state */
#define OFF 1 /* To Set Output to OFF state */
/*** Select output settings - Choose only one from each ***/
/** Output Control Method **/
#define TRIAC /* TRIAC Control Turns ON part way through cycle */
//#define IGBT /* IGBT Control turnd OFF part way through cycle */
/** Mains Frequency **/
//#define HZ60 /* For 60Hz Mains system */
#define HZ50 /* For 50Hz Maind system */
/*** Select Input Mode - Switches or 8 BIT ***/
#define INPUT_SWITCHES /* Use UP/DOWN Switches */
//#define INPUT_8BIT /* Use 8 Bit I/O port */
/*********** Reload value for Phase Control ************************
* ((1/(MainsFreq*2)) / 256) / (1/(Crystal Freq/4)) = TimerCount
* For 50Hz Mains @ 10Mhz Clock For 60Hz @ 10MHz Clock
* 1/(50Hz*2) = 10ms 1/(60Hz*2) = 8.3ms
* 10ms/256 = 39us 8.3ms/256 = 32us
* 1/(10MHz/4) = 0.4us 1/(10MHz/4) = 0.4us
* 39us/0.4us = 97 32us/0.4us = 80
*
* Subtract Interrupt time and other delays (Guessing at around 5)
* For 50Hz: 97 - 5 = 93 For 60Hz: 80 - 5 = 75
*
* Reload @ 50Hz = -93 or 163 Reload @ 60Hz = -75 or 181
* (Counter counts up and resets at Zero)
* NOTE: These allow a MAXIMUM num of intstruction cycles between
* interrupts of 93 for 50Hz System, or 75 for 60Hz System.
************************************************** *****************/
#ifdef HZ50
#define TIMER_RELOAD 163
#endif
#ifdef HZ60
#define TIMER_RELOAD 181
#endif
/**** I/O Ports ****/
#ifndef BITNUM
#define BITNUM(adr, bit) ((unsigned)(&adr)*8+(bit)) /* used for port defs*/
#endif
static bit CH_OUT @ BITNUM(PORTA,0); /* Phase Ctrl Output PIN */
static bit T_CH_OUT @ BITNUM(TRISA,0); /* Tris for above */
static bit ZERO_INT @ BITNUM(PORTB,0); /* Zero Cross Interrupt PIN*/
static bit T_ZERO_INT @ BITNUM(TRISB,0); /* Tris for above */
static bit SW_UP @ BITNUM(PORTA,1); /* Increase Power Switch */
static bit T_SW_UP @ BITNUM(TRISA,1); /* Tris for above */
static bit SW_DWN @ BITNUM(PORTA,2); /* Decrease Power Switch */
static bit T_SW_DWN @ BITNUM(TRISA,2); /* Tris for above */
#define D_IN PORTB /* Data Input port */
static bit D_IN_LSB @ BITNUM(PORTA,3); /* LSB For data input PORT */
static bit T_DIN_LSB @ BITNUM(TRISA,3); /* TRIS for above */
/**** Global Variables ****/
unsigned char CH_COUNT; /* Interrupt Counter */
unsigned char CH_LEVEL; /* Target Level */
bit INT_10MS; /* 10ms interrupt flag */
/************************************************** *******************
* main
************************************************** *******************/
void main(void)
{
/***** Set Up OPTION ******
* RB Pullup = Enabled = 0
* IntEdge = Rise = 1
* T0 Src = Internal= 0
* T0 Edge = L to H = 0
* Prescale = WDT = 1
* Prescale = 1:1 = 000
***************************/
OPTION=0b01001000;
/**** Set up Ports ****/
TRISA=0xFF; /* Port A as Inputs */
TRISB=0xFF; /* Port B as Inputs */
T_CH_OUT=1; /* Output Pin to High Impedance State */
CH_OUT=0; /* When Tris set to Output, pull LOW */
T_ZERO_INT=1; /* Zero Cross Interrupt Pin as INPUT */
ZERO_INT=1;
SW_UP=1; /* Switch as INPUT */
T_SW_UP=1;
SW_DWN=1; /* Switch as INPUT */
T_SW_DWN=1;
/**** Initialise Variables ****/
CH_COUNT=0; /* Set Inital output to 0% */
CH_LEVEL=0;
INT_10MS=0; /* Dont check keys till interrupt */
/**** Set Up Interrupts ****/
INTCON=0x00; /* Disable All Interrupts and clear flags */
INTE=1; /* Enable ZeroCross Interrupt */
/* Note: T0IE enable from Zero Cross Routine */
GIE=1; /* Enable Global interrupts */
/**** Main Program Loop ****/
/* Loop FOREVER */
while(1)
{
/* Check for 10ms interrupt */
if(INT_10MS)
{
INT_10MS=0; /* Clear Flag */
/* If using UP/Down Switches */
#ifdef INPUT_SWITCHES
if(SW_UP==0)CH_LEVEL++; /* Check for INCREASE Switch */
if(SW_DWN==0)CH_LEVEL--; /* Check for DECREASE Switch */
#endif
/* If using 8-bit port */
#ifdef INPUT_8BIT
CH_LEVEL=D_IN &0xFE; /* Read in all except LSB */
if(D_IN_LSB)CH_LEVEL |=0x01; /* Read in LSB */
#endif
}
}
}
/************** END OF main *******************/
/************************************************** *********************