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### Topic: how to get 4 digit decimal no. (Read 1 time)previous topic - next topic

#### maibam

##### Mar 08, 2013, 02:12 pm
i interface with analog voltage at pin no A0 and get the data. than i convert the data in to voltage but it has been showing upto 2 digit no not upto 4 digit no. but i need upto four 4 digit no so how can i get the value up to 4 digit no any suggestion.

#### AWOL

#1
##### Mar 08, 2013, 02:21 pm
Code: [Select]
`Serial.print (myFloatVoltage, 4);`
But, with 4mV resolution, this may not be what you want.

(post your code if you want help)
"Pete, it's a fool looks for logic in the chambers of the human heart." Ulysses Everett McGill.
Do not send technical questions via personal messaging - they will be ignored.
I speak for myself, not Arduino.

#### robtillaart

#2
##### Mar 08, 2013, 10:06 pm
do you mean preceding zero's?  e.g. 0024 mV?
Rob Tillaart

Nederlandse sectie - http://arduino.cc/forum/index.php/board,77.0.html -
(Please do not PM for private consultancy)

#### BlackSnake

#3
##### Mar 09, 2013, 04:36 am
With a print function you can define how many 0's you want after the decimal point
ie print(a0,2); will print to 2 decimal places.
I use this for voltages myself but I have found sometimes if the voltage is under ten and using an LCD 2 line display I will get 3 decimal places instead of 2.
Not sure if this problem occurs on serial monitor.
Hope this helps

#### robtillaart

#4
##### Mar 09, 2013, 08:13 am
Quote
I use this for voltages myself but I have found sometimes if the voltage is under ten and using an LCD 2 line display I will get 3 decimal places instead of 2.

Can you make a test application that shows this behaviour?
Rob Tillaart

Nederlandse sectie - http://arduino.cc/forum/index.php/board,77.0.html -
(Please do not PM for private consultancy)

#### PaulS

#5
##### Mar 09, 2013, 01:53 pm
Quote
Can you make a test application that shows this behaviour?

I'd guess that it only happens when the value drops from over 10 to under 10, and OP isn't clearing the LCD display.