Show Posts
Pages: [1]
1  Using Arduino / Displays / Re: LCD weird characters being displayed on: June 03, 2013, 02:20:40 pm
Thanks for your answers!

I'll try with a new display, though this is the second one where I am seeing this error.

Thanks for pointing out the part about the & sign. It does work however, the reference says the single & is a BITWISE and. (Though it wasn't my intention to use this)


2  Using Arduino / Displays / LCD weird characters being displayed on: June 02, 2013, 05:05:32 pm
I get some kind of display error with my LCD. It is programmed as a clock.
The error does not occur at once - some times it takes several hours or days

I've attached an image of it.
Do any of you know what this might be?

This is my code for displaying time:



Code:
 if (previousSec != now.second()) {
    previousSec = now.second();
    delay(100);


    if (setAlarmState == 0 & setCalibState == 0) {
      lcd.clear();
      if(now.hour() < 10) {
        lcd.print("0");
        lcd.print(now.hour(), DEC);
      }
      else {
        lcd.print(now.hour(), DEC);
      }
      lcd.print(":");
      if(now.minute() < 10) {
        lcd.print("0");
        lcd.print(now.minute(), DEC);
      }
      else {
        lcd.print(now.minute(), DEC);
      }
      lcd.print(":");
      if(now.second() < 10) {
        lcd.print("0");
        lcd.print(now.second(), DEC);
      }
      else {
        lcd.print(now.second(), DEC);

      }
      if (alarmOn == 1 & alarm != 1) {
        lcd.print("* ");

        lcd.print(analogRead(A1));
      }

      if (alarm == 1) {
        lcd.print(" ");
          lcd.print(average);

        
      }

    }
  }    
3  Using Arduino / General Electronics / Re: Float charging NiCd/NiMh on: February 21, 2013, 08:39:10 am
Thanks for all your answers :-)

@Docedison, cool to store battery info in the EEprom, but I'm actually trying to avoid having to sense the end of charge, and instead just use a fixed voltage (equal to the batteries full charge voltage) and a fixed amp.

@BillHo, I've read this document prior to posting and was thrilled that I could trickle charge the battery indefinitely, but when I researched it further every other source I found said a battery should never be trickle chargede for prolonged times.

A floatcharge (same voltage as the battery instead of a much higher) should be able to run indefinitely, but I am unsure if it can ever reach the final voltage.

For example, I have a 7.2V 1000Mah battery which full charge voltage is about 7.8V.
If the battery gets drained to a low voltage e.g. 6.4V and I apply 7.8V external power at 10Mah – Will the battery ever actually reach 7.8V? And will this be safe?

(Sorry if this is a ridicules question, I'm still trying to learn)
4  Using Arduino / General Electronics / Float charging NiCd/NiMh on: February 20, 2013, 08:37:57 pm
Hi,

I'm trying to build a battery charger for a 7.2V backup battery for powering my Arduino project.
I've build a simple backup circuit using diodes, and now I'm researching the charger part.

The project I'm working on is meant to be plugged into a powersource 24/7, and Ideally the battery will never be used - but it still needs to be there just in case.

So I was wondering if it would be possible to constantly charge the battery with 7.2V and C/some-low-number amps?
I know the battery wouldn't reach max capacity and that it might take a long time, but would it be possible to charge it to 7.2V like this? Even if the battery started out flat?

Any help would be greatly appreciated.
Pages: [1]