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The following program:
ADCIN 0, PRE
PRE = (PRE */500)>>2
PRE = ((((PRE * 10/5) + 95)/9)
How do i display the result of PRE on a LCD, correct to 2 decimal values?
Assuming
1st case : PRE = 800
After the formula, PRE = 97.36111111
How to display "97.36" on LCD?
2nd case : PRE = 900
After the formula, PRE = 108.2118
How to display "108.22" on LCD?
Thank you.
The secret to doing things like this is easily to scale your math. If you need two decimal places in the range 0-99.99 then just scale so your math produces results between 0-9999 (ie 100 times bigger than you need) and take the last two digits as your decimal places.
Whatever you do must however fit inside a word variable, so the biggest number you can play with is 65535 - therefore with this method to two decimal places, the biggest number you can have is 655.35
Melanie
Thanks, i've already figured out the code.
btw, how do i deal with numbers that are bigger than 65535?
Just curious though...
Just another question:
The 16877 uses the voltage supply as its reference voltage by default. Meaning that by default,
VREF- = 0V
VREF+ = 5V
How do i change the reference voltages? Is there a way where i can do it directly by just programming the PIC? Or do i need an external connection?
For example,change to
VREF- = 2.5
VREF+ = 4V
THanks.
If you look in the data sheet of the 877 then you see that
ADCON1 register can be set to a mode for Vref+ and Vref- and some other analog or digital inputs
page 112 of the data sheet
And if you put in you programm ADCON1 = %1enz
than you can programm you pins as you like.
succes