Ok , Thanks Bruce I will have a look to longs as suggested.
I am writing a program in order to control the Analog Device AD9912 DDS: this device will be used as a RF signal generator for radio ham use. The point is that I have to multiply a number as like as
2^48/1000000000 ( 281474.976711) by another number that is the readout of the real output frequency ( from 1 Hz to 400 MHz ) . At the moment the Melabs FP works well and gives me the correct output frequency.
Unfortunately i can not put the " DDS" piece of program in a subroutine : in this case i do have no errors after compiling but the 16F877 does not work.
And, if I recall the "DDS" piece of program more than three times in my program i do have the same result.

>> question: how can i set the HS oscillator using the Mpasm and pic16f877 with no problem ?

Thanks a lot.
Ambrogio
IW2FVO




Quote Originally Posted by Bruce View Post
MeLabs has a nice intro to longs here: http://www.microengineeringlabs.com/...cles/longs.pdf