Constant out of the valid range

prayami · Joined: 22 Dec 2004 Posts: 78

Hi...Anybody figure it out?

I am using 18F4525 and CCS PCH Compiler.

I want to make one line of code instead of following two lines.
Where
int16 NewRPM;
int8 CylNum;
int32 TimerCycle;

PCM programmer · Joined: 06 Sep 2003 Posts: 21708

It appears that CCS constants are signed 32-bit integers, not unsigned.

ckielstra · Joined: 18 Mar 2004 Posts: 3680 Location: The Netherlands

It seems like an internal compiler bug to me where the compiler is working with signed 32-bit integers instead of unsigned (in an ANSII compiler this would be the correct behaviour, but CCS has all variables unsigned by default)..
The specified constant is an unsigned integer and fits in the range specified in the error message, so I consider this a compiler error.

A dirty workaround:

prayami · Joined: 22 Dec 2004 Posts: 78

Hi..

Thanks for reply. But as my number 2400000000 is positive then it must
fit with unsigned int32 bit. And if you check the number carefully it is
bigger than signed int32 bit. So if I cast it to signed int32 then,
it disturbed my RPM calculation.

Error:
Constant out of the valid range -1894967296 is not 0..4294967295

If you focus on error. Then it seems that compiler is not treating it like
unsigned int32. So casting it into signed int32 can solve the compilation
error but turns to give wrong RPM calculation as my number is bigger than
signed int32.

Is it really bug? Can you please try in your program?

Mark · Joined: 07 Sep 2003 Posts: 2838 Location: Atlanta, GA

More efficient to do this:

NewRPM = (1171875/(TimerCycle*CylNum) );
NewRPM *= 2048;

ckielstra · Joined: 18 Mar 2004 Posts: 3680 Location: The Netherlands