Converting from Int to float

anze — Mon, 17 Dec 2012 11:50:37 GMT

Hello,

I have a strange behaviour in my project. I would like to receive a 32bit value via CAN and interprete it as a float value.

But the conversion to float seems to be wrong.

For example when I try to do the following:

int32_t fixTest = 0x3fc00000; //should be 1.5

float testValue = (float)fixTest;

In my case test Value is 1.06956e9 instead of the right value 1.5;

What am I missing here? Is something wrong with my project settings?

I am using Codewarrior 10.3 and MPC5643L (Leopard).

Thanks in advance.

Re: Converting from Int to float

kef — Sat, 05 Jan 2013 06:57:36 GMT

You get what is specified in subject, big integer is converted to float correctly. But I see you want to treat integer as a binary representation of float. Try this:

float testValue;

*(int32_t*)&testValue = fixTest;

typedef union{int32_t i, float f} intfloat;

intfloat tv;

tv.i = fixTest;

testValue = tv.f;

topic Converting from Int to float in CodeWarrior for MCU

Converting from Int to float

Re: Converting from Int to float