reading output of CO detector module with pic16f690 micrcontroller
im designing an carbon monoxide detector for my project. I am a new user to the pic microcontroller.
I am programming in C.
I have an CO detector module in place. I am trying to take the alarm signal from that and get the microcontroller to give me an output (like a LED lighting up).
hardware connections:
1) RC2 is connected to the CO detector's heater - needed to drive the CO detector
1) RC1 is connected to the alarm pin of the CO detector
I want to be able to light up the RCO LED when the alarm is triggered on the CO detector. I have used the RC3 LED as an indicator of when the CO module is in its purge phase.
here is my code
/*********************************************************
Configuration of PicKit
*********************************************************/
#include <pic.h> // Include HITECH CC header file
__CONFIG (INTIO & WDTDIS & PWRTDIS & MCLRDIS & BORDIS
& UNPROTECT & IESODIS & FCMDIS );
//Internal clock, Watchdog off, MCLR off, Code Unprotected
/*********************************************************
Est. Variables to be used in Program
*********************************************************/
int alarm = 0;
// Create A/D storage value and set it to 0
int index = 0;
// Est. counter index
int index2 =0;
void pause( unsigned short usvalue );
// Est. pause routine function
void msecbase( void );
// Est. millisecond base function
/*********************************************************
Program
*********************************************************/
main()
{
ANSEL = 0; // No Analog inputs yet
CM1CON0 = 0; // Initialize Comparator 1 off
CM2CON0 = 0; // Initialize Comparator 2 off
PORTC = 0x00; // Clear PortC port
TRISC = 0x02; // RC1 I/O input, rest of PortC I/O outputs
while(1==1) // Loop forever
{
RC2 = 1; // Set HSW to 5 volts (heater voltage)
// The following while loop controls the minute long purging cycle of the Carbon Monoxide Detector
index = 60;
// Set index to 60 - will serve as a timer for the purging cycle
while (index > 0)
// Loop will run as long as index is greater than zero
{
RC2 = 1;
if (RC1 == 1)
{
RC0 = 1;
pause(1000); // Delay for 1 sec
}
if (RC1 == 0)
{
RC0 =0;
pause(1000);
}
index = index -1;
RC3 = 1;
// Turn on RC3 LED during purging cycle
}
// The following while loop controls the minute and a half long detecting cycle of the Carbon Monoxide Detector
index2 = 78;
// Set index2 to 78 - will serve as a timer for the purging cycle
RC3 = 0;
// Turn off RC3 LED
while(index2 > 0)
{
index = 56;
// Set index to 56 - will serve as a timer for the purging cycle
while(index > 0)
{
RC2 = 1;
// Turns HSW voltage on (5 V)
pause(15);
// Calls on the pause function for a 15 millisecond delay
RC2 = 0;
// Turns HSW voltage off (0 V)
pause(3);
// Calls on the pause function for a 15 millisecond delay
// The turning on and off of the HSW voltage serves to a pulse width modulate the voltage and obtain a voltage of 1.4 V for the detector phase
index = index -1;
if (RC1 == 1)
{
RC0 = 1;
}
if (RC1 == 0)
{
RC0 = 0;
}
}
index2 = index2 -1;
}
} // End while
} // End main
The Following is the Code for the pause function and msecbase
//*******************************************************
//pause - multiple millisecond delay routine
//*******************************************************
#include <pic.h> // Include HITECH CC header file
void msecbase( void ); //Establish millisecond base function
void pause( unsigned short usvalue )
{
unsigned short x;
for (x=0; x<=usvalue; x++) //Loop through a delay equal to usvalue
{ // in milliseconds.
msecbase(); //Jump to millisec delay routine
}
}
/********************************************************
* msecbase - 1 msec pause routine *
* The Internal oscillator is set to 4 Mhz and the *
* internal instruction clock is 1/4 of the oscillator. *
* This makes the internal instruction clock 1 Mhz or *
* 1 usec per clock pulse. *
* Using the 1:4 prescaler on the clock input to Timer0 *
* slows the Timer0 count increment to 1 count/4 usec. *
* Therefore 250 counts of the Timer0 would make a one *
* millisecond delay (250 * 4 usec). But there are other *
* instructions in the delay loop so using the MPLAB *
* stopwatch we find that we need Timer0 to overflow at *
* 243 clock ticks. Preset Timer0 to 13 (0D hex) to make *
* Timer0 overflow at 243 clock ticks (256-13 = 243). *
* This results in a 1.001 millisecond delay which is *
* close enough. *
*********************************************************/
#include <pic.h> // Include HITECH CC header file
void msecbase(void)
{
OPTION = 0b00000001; //Set prescaler to TMRO 1:4
TMR0 = 0xD; //Preset TMRO to overflow on 250 counts
while(!T0IF); //Stay until TMRO overflow flag equals 1
T0IF = 0; //Clear the TMR0 overflow flag
}
Please help me. i dont know why I cant get the RC0 led to turn on when the alarm conditions of the CO detector module are on.
im designing an carbon monoxide detector for my project. I am a new user to the pic microcontroller.
I am programming in C.
I have an CO detector module in place. I am trying to take the alarm signal from that and get the microcontroller to give me an output (like a LED lighting up).
hardware connections:
1) RC2 is connected to the CO detector's heater - needed to drive the CO detector
1) RC1 is connected to the alarm pin of the CO detector
I want to be able to light up the RCO LED when the alarm is triggered on the CO detector. I have used the RC3 LED as an indicator of when the CO module is in its purge phase.
here is my code
/*********************************************************
Configuration of PicKit
*********************************************************/
#include <pic.h> // Include HITECH CC header file
__CONFIG (INTIO & WDTDIS & PWRTDIS & MCLRDIS & BORDIS
& UNPROTECT & IESODIS & FCMDIS );
//Internal clock, Watchdog off, MCLR off, Code Unprotected
/*********************************************************
Est. Variables to be used in Program
*********************************************************/
int alarm = 0;
// Create A/D storage value and set it to 0
int index = 0;
// Est. counter index
int index2 =0;
void pause( unsigned short usvalue );
// Est. pause routine function
void msecbase( void );
// Est. millisecond base function
/*********************************************************
Program
*********************************************************/
main()
{
ANSEL = 0; // No Analog inputs yet
CM1CON0 = 0; // Initialize Comparator 1 off
CM2CON0 = 0; // Initialize Comparator 2 off
PORTC = 0x00; // Clear PortC port
TRISC = 0x02; // RC1 I/O input, rest of PortC I/O outputs
while(1==1) // Loop forever
{
RC2 = 1; // Set HSW to 5 volts (heater voltage)
// The following while loop controls the minute long purging cycle of the Carbon Monoxide Detector
index = 60;
// Set index to 60 - will serve as a timer for the purging cycle
while (index > 0)
// Loop will run as long as index is greater than zero
{
RC2 = 1;
if (RC1 == 1)
{
RC0 = 1;
pause(1000); // Delay for 1 sec
}
if (RC1 == 0)
{
RC0 =0;
pause(1000);
}
index = index -1;
RC3 = 1;
// Turn on RC3 LED during purging cycle
}
// The following while loop controls the minute and a half long detecting cycle of the Carbon Monoxide Detector
index2 = 78;
// Set index2 to 78 - will serve as a timer for the purging cycle
RC3 = 0;
// Turn off RC3 LED
while(index2 > 0)
{
index = 56;
// Set index to 56 - will serve as a timer for the purging cycle
while(index > 0)
{
RC2 = 1;
// Turns HSW voltage on (5 V)
pause(15);
// Calls on the pause function for a 15 millisecond delay
RC2 = 0;
// Turns HSW voltage off (0 V)
pause(3);
// Calls on the pause function for a 15 millisecond delay
// The turning on and off of the HSW voltage serves to a pulse width modulate the voltage and obtain a voltage of 1.4 V for the detector phase
index = index -1;
if (RC1 == 1)
{
RC0 = 1;
}
if (RC1 == 0)
{
RC0 = 0;
}
}
index2 = index2 -1;
}
} // End while
} // End main
The Following is the Code for the pause function and msecbase
//*******************************************************
//pause - multiple millisecond delay routine
//*******************************************************
#include <pic.h> // Include HITECH CC header file
void msecbase( void ); //Establish millisecond base function
void pause( unsigned short usvalue )
{
unsigned short x;
for (x=0; x<=usvalue; x++) //Loop through a delay equal to usvalue
{ // in milliseconds.
msecbase(); //Jump to millisec delay routine
}
}
/********************************************************
* msecbase - 1 msec pause routine *
* The Internal oscillator is set to 4 Mhz and the *
* internal instruction clock is 1/4 of the oscillator. *
* This makes the internal instruction clock 1 Mhz or *
* 1 usec per clock pulse. *
* Using the 1:4 prescaler on the clock input to Timer0 *
* slows the Timer0 count increment to 1 count/4 usec. *
* Therefore 250 counts of the Timer0 would make a one *
* millisecond delay (250 * 4 usec). But there are other *
* instructions in the delay loop so using the MPLAB *
* stopwatch we find that we need Timer0 to overflow at *
* 243 clock ticks. Preset Timer0 to 13 (0D hex) to make *
* Timer0 overflow at 243 clock ticks (256-13 = 243). *
* This results in a 1.001 millisecond delay which is *
* close enough. *
*********************************************************/
#include <pic.h> // Include HITECH CC header file
void msecbase(void)
{
OPTION = 0b00000001; //Set prescaler to TMRO 1:4
TMR0 = 0xD; //Preset TMRO to overflow on 250 counts
while(!T0IF); //Stay until TMRO overflow flag equals 1
T0IF = 0; //Clear the TMR0 overflow flag
}
Please help me. i dont know why I cant get the RC0 led to turn on when the alarm conditions of the CO detector module are on.
