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#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
/*
Page about div
http://bisqwit.iki.fi/story/howto/bitmath/#DivAndModDivisionAndModulo
*/
uint8_t div20u8( uint16_t num )
{
uint16_t a = num;
uint16_t b = 20;
uint16_t r = 0;
uint16_t m = 1;
while ( b < a )
{
b = b << 1;
m = m << 1;
}
do
{
if ( a >= b )
{
a = a - b;
r = r + m;
}
b = b >> 1;
m = m >> 1;
} while ( m != 0 );
return (uint8_t)r;
}
int main()
{
uint32_t a = 10000;
uint32_t b = 5;
uint32_t r = 0;
uint32_t m = 1;
printf("%04x(%d) %04x(%3d) %04x(%3d) %04x(%3d)\n",a,a,b,b,r,r,m,m);
while ( b < a )
{
b = b << 1;
m = m << 1;
printf("%04x(%3d) %04x(%3d) %04x(%3d) %04x(%3d)\n",a,a,b,b,r,r,m,m);
}
do
{
if ( a >= b )
{
a = a - b;
r = r + m;
}
b = b >> 1;
m = m >> 1;
printf("%04x(%3d) %04x(%3d) %04x(%3d) %04x(%3d)\n",a,a,b,b,r,r,m,m);
} while ( m != 0 );
return 0;
}
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