Real-Time Clock. Keeps track of current date/time.
0
votes
0answers
23 views
RTC resets when power is off
I have a few RTC modules with a batteries. All of them have this same issue with my project.
They work fine when connected via USB. But if I disconnect the power then reconnect they reset to Jan 1 ...
0
votes
1answer
21 views
Using UART to Set RTC
I'm using an Adafruit NRF8001 Low Energy Bluetooth module and a Real Time Clock module with my Arduino board. I want to connect to the BLE module using UART to set the clock. I'll also be using UART ...
0
votes
2answers
62 views
Delay workaround needed for RTC and LCD-shield buttons
Following configuration:
Arduino UNO R3
Real Time Clock DS1307RTC
LCD1602 Shield with buttons
Photo resistor
DHT11 (Temp & Humidity Sensor)
I need the function delay(1000) to display the ...
2
votes
1answer
47 views
What will use less memory, an array or if … else?
I'm trying to make my sketch smaller. Right now I use an array for the AM/PM part of my time display. My thinking is this makes it easy to change the formatting:
char* ampms[]= {"am", "pm"};
void ...
0
votes
3answers
74 views
One free pin. Need to display output for the user?
I'm working with lightblue bean. I have a device that writes data to an SD card on a long button press and switches what will be written (from a list of 5 items) on short button press.
The output, ...
0
votes
1answer
36 views
Cannot print the first number of the date with RTC module
I am using this real-time-clock module to keep track of the time for a project:
http://www.dfrobot.com/wiki/index.php/Real_Time_Clock_Module_(DS1307)V1.1(SKU:DFR0151)
I have hooked up the respective ...
1
vote
4answers
66 views
Creating a clock using Arduino
I want to make a large clock, 16 inch x 7.5 inch, which will display dd Month yyyy.
What would be the best way to do this?
Does Arduino have a built in clock, and I'd just need logic to turn on/off ...
0
votes
1answer
55 views
Set dynamically hour - DS1307
I want keep my RTC1307 always updated with my server, so I created this code to first search the time on the server then passes to getServerTime() function to divide it and set in the RTC. I use the ...
0
votes
1answer
126 views
RTC square wave
I have a DS3231 Real Time Clock module and I'd like to use the Square Wave output.
I wonder how can I set the frequency of the pulse?
How long is the (time) length of the pulse?
UPDATED QUESTION
...
0
votes
3answers
98 views
need help for saving the millis function when arduino was rebooted
I have two questions want to ask
I'm using Arduino Uno with 16*2 LCD Blue ( also I have temp. sensor and two motors also 3 limit switches) ,, my code is working good, but sometimes my lcd stop ...
2
votes
2answers
157 views
RTC and SD works separately but not together
I am running small project. I wanted to use Arduino Mega 2560 v3, PIR sensor, microSD card module and RTC1307 module, some leds, buttons and buzzer. To enable and disable motion detection and when ...
0
votes
2answers
50 views
Error while saving data in text file
I created a function that saves the timestamp in a text file, but it saves unreadable. Full of invalid characters, example: Ÿ@ O ƒº!¥ Ÿ@ O ƒº!¥ Ÿ@ O ƒº!¥ Ÿ
#include <Wire.h>
...
0
votes
0answers
30 views
Is it possible to obtain time and date from PC time using Ethernet shield OFFLINE?
I'm looking into using the local time of the PC via Ethernet but without an Internet connection. My project uses only LAN so there's no internet.
Not considered Options:
The RTC library uses RTC ...
0
votes
1answer
135 views
DS3231 DTCXO and GPS
I am experimenting with this idea: keep a DTCXO in sync with some frequency standard. I have all the parts I can afford, but I cannot figure out a way to do it.
Parts I have: Arduino Leonardo, a ...
0
votes
1answer
118 views
Reading atomic radio clock
i have some data logging to do. And i want some what accurate time meaning accuracy has to be +/- 1 minute.
I have considered a RTC, but then i thought. When i was 10 i got a watch that kept time ...
0
votes
2answers
149 views
datalogging sampling frequency bottleneck
My datalogging system which consits of the Flora, RTC, SD card breakout board, LSM9DS0 sensor is shown in the picture below;
https://www.dropbox.com/s/d8pwcn59nq11lzs/2014-11-25%2012.26.56.jpg?dl=0
...
