June 10, 2012
by Pew446
|
Well I wanted to hook up my charlieplexed array to the PWM so I could change the brightness of the LEDs, but I'm under the impression I can only use one pin per timer (Right?), and I have 5 wires I need hooked up to individual pins. So I tried to copy the Valentines Heart method of lowering brightness, but I'm probably making a ton of mistakes. Either way, here's my code, and the issue is that the LED is always on, no matter what I have set as the duty.
#include <stdio.h>
#include <string.h>
#include <avr/io.h>
#include <avr/interrupt.h>
#include <avr/pgmspace.h>
#include <inttypes.h>
#include "../libnerdkits/delay.h"
#include "../libnerdkits/uart.h"
#define F_CPU 14745600
#define R1 (1<<PC1)
#define R2 (1<<PC2)
#define R3 (1<<PC3)
#define R4 (1<<PC4)
#define R5 (1<<PC5)
volatile uint8_t getd[1];
volatile uint8_t incrementor;
inline void setled(char i, char j, char o){
if(o==1){
if(i==1){
if(j==2){
DDRC |= R1 | R2;
PORTC |= R1;
PORTC &= ~R2;
}
else if(j==3){
DDRC |= R1 | R3;
PORTC |= R1;
PORTC &= ~R3;
}
else if(j==4){
DDRC |= R1 | R4;
PORTC |= R1;
PORTC &= ~R4;
}
else if(j==5){
DDRC |= R1 | R5;
PORTC |= R1;
PORTC &= ~R5;
}
}
else if(i==2){
if(j==1){
DDRC |= R2 | R1;
PORTC |= R2;
PORTC &= ~R1;
}else if(j==3){
DDRC |= R2 | R3;
PORTC |= R2;
PORTC &= ~R3;
}else if(j==4){
DDRC |= R2 | R4;
PORTC |= R2;
PORTC &= ~R4;
}else if(j==5){
DDRC |= R2 | R5;
PORTC |= R2;
PORTC &= ~R5;
}
}
else if(i==3){
if(j==1){
DDRC |= R3 | R1;
PORTC |= R3;
PORTC &= ~R1;
}else if(j==2){
DDRC |= R3 | R2;
PORTC |= R3;
PORTC &= ~R2;
}else if(j==4){
DDRC |= R3 | R4;
PORTC |= R3;
PORTC &= ~R4;
}else if(j==5){
DDRC |= R3 | R5;
PORTC |= R3;
PORTC &= ~R5;
}
}
else if(i==4){
if(j==1){
DDRC |= R4 | R1;
PORTC |= R4;
PORTC &= ~R1;
}else if(j==2){
DDRC |= R4 | R2;
PORTC |= R4;
PORTC &= ~R2;
}else if(j==3){
DDRC |= R4 | R3;
PORTC |= R4;
PORTC &= ~R3;
}else if(j==5){
DDRC |= R4 | R5;
PORTC |= R4;
PORTC &= ~R5;
}
}
else if(i==5){
if(j==1){
DDRC |= R5 | R1;
PORTC |= R5;
PORTC &= ~R2;
}else if(j==2){
DDRC |= R5 | R2;
PORTC |= R5;
PORTC &= ~R2;
}else if(j==3){
DDRC |= R5 | R3;
PORTC |= R5;
PORTC &= ~R3;
}else if(j==4){
DDRC |= R5 | R4;
PORTC |= R5;
PORTC &= ~R4;
}
}
}
}
inline void alloff() {
DDRC &= ~( (1<<PC1) | (1<<PC2) | (1<<PC3) | (1<<PC4) | (1<<PC5) );
PORTC &= ~( (1<<PC1) | (1<<PC2) | (1<<PC3) | (1<<PC4) | (1<<PC5) );
}
inline void init_pwm() {
incrementor = 0;
// Timer0 CK/8 (7000Hz)
TCCR0B = (1<<CS01) | (0<<CS00);
TIMSK0 = (1<<TOIE0);
}
SIGNAL(SIG_OVERFLOW0) {
//keep a counter to provide duty cycle
incrementor++;
if(incrementor == 64)
incrementor = 0;
alloff();
if(getd[0] > incrementor){
setled(1,2,1);
}else{
setled(1,2,0);
}
}
int main() {
init_pwm();
sei();
int i;
while(1){
for(i=0;i<64;i++){
getd[0]=i;
delay_ms(10);
}
i=0;
}
return 1;
}
Excuse my novice coding, I'm not used to C. |
June 10, 2012
by Pew446
|
Well I guess I should say the LED is always at full brightness no matter the duty. |
June 10, 2012
by Pew446
|
Here is my schematic if it helps:
|
June 10, 2012
by Pew446
|
Wow what silly mistakes. I forgot to specify what happens when setled()'s third argument is a 0 (turn off the led.)
I hope someone finds this thread partly useful. |
