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Topic: ESR meter with Arduino (Read 76 times) previous topic - next topic

grant1842

Thanks for your help,.
I do not have any bc337 npn trans in my parts bench.

I do have some 2N4401 . Will this be a suggestible replacement ?
Thanks again

szmeu

@grant1842

2N4401 as I see from datasheet should do the job.  :)

grant1842

Zero Meter.

The lcd I am using is only useing a 2 wire (A4, A5) to show info.

I am confused on the schematic as it uses several connections to the lcd .

I am worndering how to wire up the push button ZERO with my 2 wire LCD display.

Thanks for your help.

szmeu

@grant1842

The button for the zeroing has nothing to do with the LCD, it is just a button tied to a digital pin (in this case D0) which has the pull up resistor enabled, when you push the button that digital pin is put to the ground and this condition is tested in this section of code:

 
Code: [Select]
if(!digitalRead(BUTTON_PIN)){
    lcd.clear();
    lcd.print("Zeroing...");
    esrCal = (miliVolt)/current;
    lcd.print(" done!");
    lcd.setCursor(0,1);
    //writing calibration value into EEPROM so we don't have to calibrate on restart
    eeprom_write_block((const void*)&esrCal, (void*)0, sizeof(esrCal));
    lcd.print("saved to EEPROM");
    delay(400);
  }


I suppose you have some kind of serial interface LCD so you must set up your LCD to use a proper library, the schematic here shows  HD44780 type LCD wiring using 4bit mode, more on LCD you can find here: http://arduino.cc/playground/Code/LCD

grant1842

Thanks for all your comments.

I have bread boarded this project and the displays reads(Zeroing Done saved to EEPROM) , it is like it is stuck in a loop .
I thought I may be doing something wrong so I used Proteus to do a simulation and I get the same reslut.
Can you look at the schematic and see if I am doing something wrong.

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