Re: [avr-gcc-list] Avr-libc Floating Point Problem

[Thomas D. Dean]

On Fri, 2011-01-14 at 20:44 -0200, Marcelo Politzer wrote:

That fixed my problem  I have some surprises in the results.

Scope  Timer1  What
4.3us   3.5us  Convert tcnt1 to float
156us   154us  sprintf M_PI
10us    8.5us  float mult
8.5us   7.0us  float add
1.5us     0us  float div   - sometimes shows 0.5us
1.5us     0us  float sin   - sometimes shows 0.5us
2.3us     0us  long long mult
2.3us     2us  atan2         <-- for testing replaced long long mult
                                 in the posted code

I do not understand the timer1 values for the last 3.

The results mostly agree with scilab 5.3.

Now, to hook up the uM-FPU and repeat the tests.

tomdean