Questions tagged [rtc]
Real-Time Clock. Keeps track of current date/time. Some have batteries like the DS3231, and the DS3231 also has programmable alarms that can interrupt an Arduino.
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RTC DS1307 gives random and incorrect time value [closed]
The RTC module can output the hours as 165, and the minutes as 165. This is some random number that is different every time. Everything works fine, but at random times I get this. Maybe once every ...
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Code review for timer using RTC and OLED screen
I am building a small art project to display my current age with an accuracy of 1/100th of a second. I am using a XIAO SAMD21, a DS3231 RTC, and a 128x32 OLED screen. Here is what it looks like right ...
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RTC DS1307 module not working
I have a problem with an RTC: it doesn't work correctly. When I try to read date or time, I only see the characters "àààààààà" or or the program is blocked.
#include <Wire.h>
#include &...
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How to use an external 32kHz crystal for ESP32 S3 with Arduino IDE?
I want to use an external 32kHz crystal for RTC with ESP32 S3, but I didn't see any example or tutorial for Arduino IDE, Even when I asked ChatGPT, it gave me some example but the code gave library ...
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Arduino code intermittent
I have an alarm for "tea time", "lunch time" and "tea time". It works well at times but occasionally it gets stuck on the alarm not resetting, other times it does not ...
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DS1302 RTC module running too fast
I am using a DS1302 RTC module with an Arduino Mega 2560 Rev 3. I follow steps on this website since I have no experience with RTC module before. Here are the outputs I am getting.
17:15:21.835 -> ...
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DS3231 with Arduino Nano for Timing precision
I need to synchronize two separate circuit boards working with Arduino Nano. The need is to activate one relay using Arduino-1 after 45 minutes, and another relay using Arduino-2 after 45.36 seconds. ...
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is there Raw RTC output?
I have an I2C Real Time Clock, DS3231 RTC module , and I just want something like Unix Time.
I'm using the uRTCLib, looking at the class methods
but dont see anything like that. I'm thinking there ...
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How can I use a LCD I2C and a RTC3231 on a Arduino Pro Mini?
On a small project, I have a DS3231 RTC module and a LCD I2C module that I'm trying to connect on a Arduino Pro Mini board. However, both the RTC and LCD require connecting the SDA and SCL to the pins ...
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Milliseconds using square wave RTC
i am trying to make a code that prints the time hh:mm:ss:ms using RTC,i have made it using millis() but it is not accurate +/-2 milliseconds
ho can i make it using sq wave and intterupt
here is the ...
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using RTC for storage
I keep seeing stuff about this: https://www.arduino.cc/reference/en/libraries/rtcvars/ when looking for storage for a few variables that survive turning off and on, but then it is only on ESP8266.
The ...
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Save Circularbuffer in RTC memory of ESP32
I would like to save my Circular Buffer in the RTC memory of my ESP32 when I use deep sleep. So I have initialized it with RTC_DATA_ATTR but when I go into Deep Sleep I lose the data I've saved. Is ...
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RTC DS3231 always remember the old time
I try to change time on windows to test my programing condition but RTC usually keep old time when i change time on windows and re-upload the code . I'm also removing the battery and cut the power it ...
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Second I2C on Due RTClib, can't start
I am using SDA1, SCL1 for my DS3232 with RTClib on Due. It works on a Mega2560 on SDA, SCL.
I ran I2c_test with success after I inserted
#define Wire Wire1
However with ds3231.ino this define doesnot ...
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Arduino Motor Control at a Specific Time
Hello. Currently I'm working on creating an automatic dog food dispenser. I'm using a Arduino Uno R3, an L298N stepper driver, a DS1307 RTC breakout board, a Nema 17 stepper motor, and a breadboard to ...
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How to get time from RTC after wake up from sleep?
I have a setup with an Arduino Pro Mini, a DS1307 RTC, a microSD shield and a microswitch. I've set an interrupt to the microswitch, so it'll wake up the Arduino when it changes status. Here is some ...
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Get time as 24 hour format from RTC
I have a DS3231 RTC module.
I would like to get the time from the RTC as 24 hour format not 12 hour. The library that I'm using requires that I pass in 2 Boolean values into Clock.getHour(), however ...
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Arduino RTC SD Card problem
I am using a script on an Arduino to record BME280 data onto an SD card and to display it on a lcd display. To have a valid time stamp I am also using a DS3231 RTC module. I set the time succesfully ...
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Connect multiple Arduinos to ESP32's RTC?
Depending on usage frequency, may get the occasional collision where
both test for availability at the same time - if occurring too
frequently, maybe add something simple like one arduino only does ...
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Incorrect DateTime value constructed
I'm working on alarm clock project using Arduino Nano (v 3.0, clone) and RTC module ZS-042 (containing DS3231 and EEPROM AT24C32).
The intention is to load the hours and minutes from EEPROM on start-...
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Problem understanding how to program DS3231 RTC
I need to send a pulse to an Arduino at every one hour. I don't need day, month, year etc. I just want a pulse from DS3231 at every 1 hour through the square wave pin.
https://github.com/...
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Arduino with interrupts enters in a locking state
I am quite noobish with using the interrupts on Arduino and I am facing a strange problem. I am using an Arduino Pro Mini, a light sensor and an RTC module(DS3231) which has set 2 alarms, one at ...
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Sync of Time Library and RTClib
Trying to understand the two libraries and setSyncProvider(RTC.now).
Using Arduino Uno with Adafruit ChronoDot. Aduino IDE 1.8.13.
The code below is simply to understand what is happening.
I am ...
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RTC and Time Library Problems
Want to use Arduino Time library and occasionally sync it with an external RTC (Maxim DS3231 chip). I am turning LEDs on and off based on time and using a shift register (Nexperia 74HC154PW) and ...
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Real Time clock module error-DS3231
This is not a code error I have been using DS3231 RTC module with battery. When I bought this module It worked perfectly now when I get it to use, The time is running perfectly. when I set the current ...
