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[SOLVED] arithmetic operation in C (2 decimals)

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hamsiii

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Hi all,
I have a problem of acquiring ADC data. The data should be 562 and constant, stored in ADC (10bit) memory.
To calculate the exact voltage (which is 2.74V), the operation is;
Code: 
float x = (ADC_Result*60)/1022;
float y = (x*5)/60;
However, at this point, I get 32 for x and 0 for y as I should get 32.99... for x and 2.74... for y. Dividing operators do not provide me any decimals and they round the number down. Would please help me to avoid this and get the exact numbers?

I would not use printf, instead I will send the data into LCD. So, the %.2f function will not be any use for me. So, the data will be stored in a specifier like float or int.
 

You can use typecasting, usually typecasting one variable will do all the calculations in the provided type or you can typecast the other numbers too.

Code: 
float x = ((float)ADC_Result*60)/1022;
float y = ((float)x*5)/60;

I think it will even work if you add a decimal but I would suggest the typecasting method to be in control

Code: 
float x = (ADC_Result*60.0)/1022;
float y = (x*5.0)/60;

Alex
 
Have you tried putting the decimal points in?

float x = (ADC_Result * 60.0) / 1022.0;
float y = (x * 5.0) / 60.0;
 
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