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Floating Point operation doesn't display the result

OSeme
Beginner
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I am doing a simple test of the floating point functionality for the Nios II processor. I pass two integer numbers to Nios FPU2 and perform a square root operation and division. Result of the operation expected to be a floating point. However, when I do a printf to see the result nothing displayed. Anyone knows what am I doing wrong here? See below C code and Platform Designer architecture of the system.

#include <math.h> #include "system.h" #include "float2_gcc.h" #include <stdio.h> #include <stdlib.h> #include "altera_avalon_pio_regs.h"     #define PORT1_BASE 0x00021000 #define PORT2_BASE 0x00021010 #define read_io(addr) (*(volatile int *)(addr))   int main(void) {   int in1; int d1, d2; float result, result2; volatile float test = 1.5f;   in1 = read_io(PORT1_BASE); //my macro   d1 = IORD_ALTERA_AVALON_PIO_DATA(PORT1_BASE); d2 = IORD_ALTERA_AVALON_PIO_DATA(PORT2_BASE);   result = d1/5; result2 = sqrtf(d1/5);   printf("Operand 1 integer value >>> %d \n", d1); printf("Operand 2 integer value >>> %d \n", d2); printf("Result of operation >>> %g \n", result); printf("Result of operation 2 >>> %f \n", result2); printf("Test float >>> %g \n", test);   int ret = show_gcc_inference();   /* Return value just to prevent compiler from optimizing out code. */ return ret;   }

 

I am working of float2_gcc example provided with Quartus Prime Lite 18.0 software.

 

Thanks!

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OSeme
Beginner
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Found error. I should have used type casting since d1 and d2 are integers. Also, found another thread on this forum that says that Small C library doesn't carry float data type. If Small C library option is not chosen it looks like I need at least 41k bytes more of memory. Is there way around it to be able to use float and double data types?

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JOHI
New Contributor II
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Hello,

If your calculations are minimal, you could do floating point in the fpga part of the soc.

Br.

Johi.

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