Need help for project RGB led controller.

[xgnetto]

Dear all,
I start project with rgb led, what MCU i can use, AVR or PIC ?
I have need 3 PWM Hardware not less than 10 Bit resolution, and eeprom memory inside mcu.

Thank you for any comment or example similar project.
 

xgnetto

[freddy]

Hi,

you can use AVR with 16MHz clock.

You have to do a 3 software PWM at 10bit using a timer with time base of 20us.

In C with 320 cycle of clock you have the time to do all.

With code writing in assembler, you can do 4 PWM.

[mustuva]

Hi,
This link uses PIC12F629 and 3 software PWM.

http://picprojects.org.uk/projects/rgb/index.asp

Source code http://petesworld.demon.co.uk/code/rgbsa-inet.zip
Schematic http://picprojects.org.uk/projects/simplergb/SimpleRGBdriver_sch.pdf

[necati]

#include <12F675.h>
#use delay (clock=4000000)//ccs
#fuses INTRC_IO,noWDT,PUT,NOBROWNOUT,noPROTECT,NOPUT,NOCPD,MCLR

#define    led1      PIN_A0//yes  led 220R +V
#define    led2      PIN_A1//mavi led 220R +V
#define    led3      PIN_A2//kirm led 220R +V

#ROM 0x3ff = {0x3480}

BYTE CONST TABLE [120]= {
                250,80,0,220,70,0,200,30,0,
                180,0,30,150,0,60,120,0,80,
                100,0,120,80,0,150,60,0,180,
                30,0,200,20,0,230,0,20,250,
                0,40,220,0,60,200,0,80,170,
                0,100,150,0,120,120,00,150,100,
                0,180,80,0,200,60,0,220,40,
                0,250,20,10,220,0,20,200,0,
                30,200,0,40,170,0,50,10,0,
                250,0,0,220,0,0,200,0,0,
                180,0,0,150,0,0,120,0,0,
                0,0,100,0,0,120,0,0,140,
                0,0,180,0,0,200,0,20,250,
                0,40,220,
            };
////////////////////////////////////////////////////////////////////////
void main() {

int16 titrval, dampval;
int led1val,led2val,led3val, deger,tablsay,lighthed1,lighthed2,lighthed3;
SET_TRIS_A   (0b00001000);
SETUP_TIMER_1(T1_DISABLED );
setup_comparator(NC_NC_NC_NC);
setup_ADC_ports(NO_ANALOGS);

   tablsay = 0;
/////////////////////////////////////////////////////////////////////////
while(1){

deger++;
titrval++;
dampval++;
//////////////////////////////////////
if (titrval == 2000){   //tablodan set say al
   titrval = 0;
   if (tablsay >= 98) tablsay = 0;
   lighthed1 = table [tablsay];
   lighthed2 = table [tablsay+1];
   lighthed3 = table [tablsay+2];
   tablsay+=3;}
///////////////////////////////////////
if (dampval ==600){//soft
   dampval = 0;
   if (led1val < lighthed1) led1val++;
   if (led1val > lighthed1) led1val--;
   if (led2val < lighthed2) led2val++;
   if (led2val > lighthed2) led2val--;
   if (led3val < lighthed3) led3val++;
   if (led3val > lighthed3) led3val--;}
////////////////////////////////////////
if( deger < led1val )
   {
   output_low(led1);
   }
else
   {
   output_high(led1);
   }

if( deger < led2val )
   {
   output_low(led2);
   }
else
   {
   output_high(led2);
   }

if( deger < led3val )
   {
   output_low(led3);
   }
else
   {
   output_high(led3);
   }
}

}

[paxmowa]

The original poster wants 3 HARDWARE PWM channels,

There are AVR chips that can do that, but I don't know much about those.

As for PICs, i would look into the models:

16F737, 16F747, 16F767 and 16F777

They are similar devices, the only differences are in memory size and the number of A/D channels, they all have 3 Hardware PWM channels with 10-bit resolution.

Have used these in the past with great ease, just set up the channels and write values to the used registers, nothing more, nothing less.

Regards,
Pax

[Mega32]

This is a pretty cool setup , using avr's

http://www.microsyl.com/moodlight/moodlight.html

/Mega32

[localcrack]

You can use PIC16F877A Microcontroller It has a two PWM Channel
you can generate third one by using timer1 or timer2 interrupt.