'ds1307 running to slow on attiny85

Someone know why ATTiny85 connect to ds1307 crystal get time the refresh frequency to slow?

The new time value refresh change at 4 second. It running normal on arduino(UNO). ATTiny clock (internal 8 Mhz)

Thx.

    #include <TinyWireM.h>
    #include "TinyRTClib.h"
    #include <Tiny4kOLED.h>

    RTC_DS1307 rtc; 


    void setup() {
      // put your setup code here, to run once:
      oled.begin();
      oled.clear();
      oled.on();
      oled.switchRenderFrame();
      rtc.begin();
      rtc.adjust(DateTime(2019, 3, 30, 15, 38, 0));

    }

    void loop(){
      if (! rtc.isrunning()) {
        return disconnectCrystal();
      }

      DateTime now = rtc.now();

      oled.fill(0xFF);
      oled.clear();
      oled.switchFrame();

      oled.setFont(FONT6X8);

      oled.setCursor(32, 2);
    ..  
      oled.print(now.hour(), DEC);
      oled.print(':');
      oled.print(now.minute(), DEC);
      oled.print(':');
      oled.print(now.second(), DEC);
    ..
      delay(1000);
    }
arduinoattiny


Solution 1:[1]

Try using millis() instead of delay()

https://gist.github.com/kubilisr/eaf9d488e258a2175313fb38f6f80aa2

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution Source
Solution 1 Shizuku Tsukishima

Related Questions