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Altera_Forum
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15 years ago

NIOS2 HW & DIV Instructions + FPU

Hello i am in charge of designing a system that does a lot of complex sin/cos/* instructions and i need them to be fast. I am using NIOS2-F at 100mhz in a Cyclone IV. I've enabled HW and DIV ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

I am using the 60-1 and 60-2 flags without having a FPU added to the Nios II core.

I made this tests to see if float operations are working 


static float legal; 
static float legal2; 
   legal = 3.4; 
   legal2 = 2; 
   log_msg("Multiplicando: %f  -- Dividindo: %f", legal * legal2,  legal/legal2); 
   legal = 4; 
   legal2 = 2.3; 
   log_msg("Multiplicando: %f  -- Dividindo: %f", legal * legal2,  legal/legal2); 
   legal = 4.5; 
   legal2 = 2.3; 
   log_msg("Multiplicando: %f  -- Dividindo: %f", legal * legal2,  legal/legal2); 
   legal = 4.3148981934; 
   legal2 = 2.313319843; 
   log_msg("Multiplicando: %f  -- Dividindo: %f", legal * legal2,  legal/legal2); 
   legal = 4.3148981934; 
   legal2 = 2.313319843;
The results were all good.. is my test right? If i remove those flags my processing suffer a lot of loss