It would make my little program much simpler if I could input decimal hours (1.5) as opposed to having to fiddle with minutes. Can Float be used in the library to allow this ?
You could write your own library to do this.
Or
You could use what is currently available to you.
Your decision.
.
What kind of comment is that ? I am asking what is available. Thanks for the help.
1 Like
(deleted)
As mentioned above do your own thing.
1.5*60=90
90%60=30
If you want, put it in a function.
What's the the problem?
.
Maybe it would help if I showed how I am trying to use it.
Lets suppose I want a light to turn on at 2 a.m. and off at 4:30 a.m.
If it was 2 & 4 I would just say
If now.hour >=2 && now.hour <=4
turn on the light and this works
But the 4:30 is more awkward. I have tried now.hour 4.5, no good
I have tried using minutes more than 60 (ie now.hour > 2 && now minute < 150), no good
When I try mixing hours and minutes les than 60, it turns off in between 2 & 4:30
() left out due to laziness
I won't say I'm stumped, but being able to use decimal hours would solve this issue.
Convert to minutes.
myMinutes > 120 && myMinutes < 270 // 2am to 4:30am
.
Well i just set it up for minutes >= 747 (that's 12:27 p.m. my time) & <= 750
nope. As I mentioned before, it doesn't want to respond to minutes > 60. Course I could be doing something wrong.
minutes >= 747 && minutes<= 750
Make sure you use unsigned int (an int works too)
Show us your sketch.
.
// This is supposed to turn on a light at 2 a.m. & off at 4:30 a.m. Pin 2 is an LED.
#include <Wire.h>
#include "RTClib.h"
RTC_DS1307 rtc;
void setup()
{
Serial.begin(9600);
Wire.begin();
rtc.begin();
if (! rtc.isrunning())
{
Serial.println("RTC is NOT running!");
}
//Any pin. I have used On-Board LED Pin 13 & 2 to LED
pinMode(13, OUTPUT);
digitalWrite(13,LOW);
pinMode(2, OUTPUT);
digitalWrite(2,LOW);
}
void loop()
{
DateTime now = rtc.now();
Serial.print(now.year(), DEC);
Serial.print("/");
Serial.print(now.month(), DEC);
Serial.print("/");
Serial.print(now.day(), DEC);
Serial.print(" (");
Serial.print(now.hour(), DEC);
Serial.print(":");
Serial.print(now.minute(), DEC);
Serial.print(":");
Serial.print(now.second(), DEC);
Serial.print(")");
Serial.println();
Serial.println();
delay(1000);
//The time is set as 24 hours
if (now.minute() >= 770 && now.minute() <= 775) // Set Pin 13 HIGH until Time interval exceeded, the LOW
{
digitalWrite(13,HIGH);
digitalWrite(2,HIGH);
}
else
{
digitalWrite(13,LOW);
digitalWrite(2,LOW);
}
}
I am using a 3231 rtc.
if (now.minute() >= 770 && now.minute() <= 775)
But you have not added the hour (12 in your example) to this.
Try:
if (((now.hour() * 60) + now.minute()) >= 770 && ((now.hour() * 60) + now.minute()) <= 775)
now.hour()
BTW
You can let the compiler do work for you.
ex.
12 * 60 + 50 rather than saying 770
.
hey hey, it worked.
I had to comment out the trailing now.hour() - I'm not sure what that is for.
Until your last comment, I thought my mistake was not introducing now.hour() so that the minutes would have a reference point.
what is the difference if the machine multiplies 12*60 + 50, or I just put 770 in ? Obviously it does make a difference, but I'm wondering why. You have solved my problem, so if you don't feel like going into explanations, I am still grateful.
"what is the difference if the machine multiplies 12*60 + 50, or I just put 770 in ? "
Helps prevent mistakes if you are old and you cannot multiple any more 
. . . >= 770 versus . . . >= 12*60+50
for example
int lowerTime = 12 * 60 + 50; //12:50
int upperTime = 12 * 60 + 55; //12:55
.
.
.
if (((now.hour() * 60) + now.minute()) >= lowerTime && ((now.hour() * 60) + now.minute()) <= upperTime)
.