Atmega328 clock swaying

Projects General Guidance
1

I'm a relative newbie to this so it seems like an odd question but probably one with an easy answer.

I created a sketch on my Uno and everything works right. Lots of LEDs blinking at certain intervals with some sound. When I uploaded it to my ATMmega328 the sketch works, But every once in a while the timing goes off.

To test, I simply hooked up to LEDs. One goes on for a second and off for half a second, the other goes on for 700 milliseconds and all for 500 milliseconds. They work for a while, then every once in a while one will lag in either the on or off position or both will, then they go back into sync.

I have an oscillator on pins 9 and 10 along with a 22pF capacitor on each leg.

Any thoughts would be helpful. Thanks!

2

And . . ?

3

I'm not sure what you mean by and? I'm trying to figure out how to get the timing right now with the crystal.

4

It means "and what else do you want to tell us?"

5

I'm trying to figure out why the external clock is not keeping time. Did I miss a step? Did I hook up something wrong? I'm not sure what else you might need to know

6

Would you be kind enough to upload your sketch for people to check over? Autoformat it first using Tools | Autoformat. Then Edit | Copy for forum and paste into the forum text box.

7

You missed the step where you post your schematic and your code

8

Maybe you should've led with that :slight_smile:

9 
#include <jled.h>
 
const int pinStrobeLights = 12;
const int pinNavLights = 4;

auto strobeLights = JLed(pinStrobeLights).Off();
auto navLights = JLed(pinNavLights).Off();

void setup() {
  strobeLights = JLed(pinStrobeLights).Blink(75, 925).Forever();
  navLights = JLed(pinNavLights).Blink(1000,500).Forever().DelayAfter(700);
}

void loop() {
  navLights.Update();
  strobeLights.Update ();
}

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10

I should also mention it's a 16 mHz crystal

11

You should mention it is a 16MHz crystal.
Or so I would hope.

What happens with a simple blink sketch?
Not everyone has that library.