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switchblademaster
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| using ADC values |
 Posted: Tue Jul 28, 2009 8:39 pm |
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ok........so I have decided to build a line following robot and getting a little trouble with using the values I get from the ADC inputs.
I have 6 inputs.......two to indicate left......two for center......and two for right
I have done my ADC conversion and I want to execute routines to tell the robot to move left or right. In the beginning of my main code I have the ADC setup.........but what do I do after???
I am thinking of using the switch statement to call different subroutines for different cases. I will be compring the sensors to a setpoint value and if any of the cases are true then it will execute the code.
Is there any other suggestions on how I can approach this problem???
This is my code:
| Code: |
#include <18F4520.h>
#device adc=8 //Resolution of ADC: 0-256
#device ICD=TRUE
#FUSES NOWDT //No Watch Dog Timer
#FUSES INTRC_IO //Internal RC Oscillator; no clock out
#FUSES NOPROTECT //Code not protected from reading
#FUSES NOBROWNOUT //No brownout reset
#FUSES NOPUT //No Power Up Timer
#FUSES NOSTVREN //Stack full/underflow will not cause reset
#FUSES NOLVP //No low voltage prgming, B3(PIC16) or B5(PIC18) used for I/O
#FUSES NOWRT //Program memory not write protected
#FUSES NOWRTD //Data EEPROM not write protected
#FUSES NOIESO //Internal External Switch Over mode disabled
#FUSES NOFCMEN //Fail-safe clock monitor disabled
#FUSES NOPBADEN //PORTB pins are configured as digital I/O on RESET
#FUSES NOWRTC //configuration not registers write protected
#FUSES NOWRTB //Boot block not write protected
#FUSES NOEBTR //Memory not protected from table reads
#FUSES NOEBTRB //Boot block not protected from table reads
#FUSES NOCPB //No Boot Block code protection
#FUSES LPT1OSC //Timer1 configured for low-power operation
#FUSES MCLR //Master Clear pin enabled
#use delay(clock=16M, oscillator=4M) //Clock speed of 16MHZ
#use standard_io(A1)
#define L2 PIN_A0
#define L1 PIN_A1
#define CL PIN_A2
#define CR PIN_A3
#define R1 PIN_A4
#define R2 PIN_A5
int CENTER_L;
int CENTER_R;
int LEFT_1;
int LEFT_2;
int RIGHT_1;
int RIGHT_2;
int set_point=1;
int calibrate, set_point1;
int1 i;
void main()
{
setup_ccp1(CCP_PWM);
setup_ccp2(CCP_PWM);
setup_timer_2(T2_DIV_BY_1, 255, 1); //PWM resolution 1023
setup_adc_ports(AN0_TO_AN5);
setup_adc(ADC_CLOCK_INTERNAL);
setup_adc_ports(VSS_VDD);
while(1)
{
set_adc_channel(2);
delay_us(10);
CENTER_L = read_adc();
set_adc_channel(3);
delay_us(10);
CENTER_R = read_adc();
set_adc_channel(0);
delay_us(10);
LEFT_2 = read_adc();
set_adc_channel(1);
delay_us(10);
LEFT_1 = read_adc();
set_adc_channel(4);
delay_us(10);
RIGHT_1 = read_adc();
set_adc_channel(5);
delay_us(10);
RIGHT_2 = read_adc();
if{CENTER_L>set_point}
set_pwm1_duty(CENTER_L);
set_pwm2_duty(0); |
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PCM programmer
Joined: 06 Sep 2003
Posts: 21708
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| Posted: Wed Jul 29, 2009 1:23 pm |
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You're asking questions about the design of a line-following robot program.
It's probably better to ask design questions in a pure Robotics forum.
Try these search strings in Google:
| Quote: | | line following robot CCS |
or
| Quote: | | line following robot design |
or
| Quote: | | line following robot forum |
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Guest
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| Posted: Wed Jul 29, 2009 1:33 pm |
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No sorry..........it is not about the robot design. Probably I need to state it a little clearer. I wanted to know how can I test different situations besides using if and else if statements. I was thinking about the switch statements, but I soon realized that cannot work.
So I am testing the condition of each sensor.....and using PID control to make the robot move effectively. Getting a little trouble with the testing conditions and the PID routines. But I will work on my code and test it....sorry for the misunderstanding. |
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PCM programmer
Joined: 06 Sep 2003
Posts: 21708
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| Posted: Wed Jul 29, 2009 2:03 pm |
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CCS has a driver file with some routines for a line following robot:
| Quote: | | c:\program files\picc\drivers\line_tracker.c |
They have one routine that checks the sensors. The sensor ID is passed
to the routine as a parameter (LEFT, RIGHT, or CENTER), and it selects
the appropriate A/D channel based on that. Then it reads the A/D value,
tests it, and returns a value based on whether or not it detected a
reflective surface. Maybe this can give you some ideas. |
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Switchblademaster
Guest
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| Posted: Wed Jul 29, 2009 2:32 pm |
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hey thanks.........didn't even know that was there!!
that is interesting though.........I will experiment with it.
Ugh.......the big trouble now is figuring out the PID code.......anyway thanks again  |
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