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| Author |
Message |
lor3nzo
Guest
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| multiplication bug |
 Posted: Thu Nov 13, 2008 5:04 am |
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Hi,
I'm using pcw 4.032 and the instruction
var=var*5
doesn't work, but I have the correct result with
var=var+var+var+var+var.
Why?
Thank you |
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Ttelmah
Guest
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| Posted: Thu Nov 13, 2008 5:09 am |
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Questions:
What type is 'var'?.
What value is in 'var', when you see the problem?.
Have you looked at the 'sticky' thread at the top of the forum, on 'version 4 coments'. 4.032, is 'borderline', on being a useable version. I'd not have expected something as basic as multiplication to actually give a problem - more likely, something else is failing, and being 'seen' as a problem in the multiplication....
Best Wishes |
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Guest
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| Posted: Thu Nov 13, 2008 5:19 am |
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var is a int16 variable.
This instruction doesn't work too
var1=var2*5
the two variable are int16
var1 is 0 and var2 is 6. |
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lor3nzo
Guest
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| Posted: Thu Nov 13, 2008 5:23 am |
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I've this problem with a 18F2321.
I reused this portion of code in a project with a 16f648a and everything is alright. |
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Wayne_
Joined: 10 Oct 2007
Posts: 681
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| Posted: Thu Nov 13, 2008 5:44 am |
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You are missing a semicolon var1=var2*5; <---- 
Is this your code ?
| Code: |
main()
{
int16 var1, var2;
var2 = 6;
var1 = var2 * 5;
printf("%Lu, %Lu\r\n", var1, var2);
while(true) {}
}
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?
If not WHAT is your code ?
How are you looking at the values var1 and var 2 ? |
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lor3nzo
Guest
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| Posted: Thu Nov 13, 2008 7:26 am |
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That is the code.
I watch variables with debug mode. |
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Ttelmah
Guest
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| Posted: Thu Nov 13, 2008 9:26 am |
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I think you will find that your problem is in the debug, rather than the multiplication. I seem to remember some (several) threads running at about the time that the early V4.03x compilers came out, with problems like this. Try a physical output, like Wayne is showing, and I suspect you will find that the values are fine.
Best Wishes |
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