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speeduino
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MISRA compliant maths.ino

This commit is contained in:
Josh Stewart 2017-06-19 22:02:40 +10:00
parent 4aac3c2ff9
commit 4f42c289b2
2 changed files with 10 additions and 6 deletions
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2
speeduino/maths.h
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@ -1,7 +1,7 @@
#ifndef MATH_H
#define MATH_H
int fastMap1023toX(unsigned long, int);
int fastMap1023toX(int, int);
unsigned long percentage(byte, unsigned long);
#endif

14
speeduino/maths.ino
View File

@ -5,7 +5,12 @@
//Replace the standard arduino map() function to use the div function instead
int fastMap(unsigned long x, int in_min, int in_max, int out_min, int out_max)
{
return ldiv( ((x - in_min) * (out_max - out_min)) , (in_max - in_min) ).quot + out_min;
unsigned long a = (x - (unsigned long)in_min);
int b = (out_max - out_min);
int c = (in_max - in_min);
int d = (ldiv( (a * (long)b) , (long)c ).quot);
return d + out_min;
//return ldiv( ((x - in_min) * (out_max - out_min)) , (in_max - in_min) ).quot + out_min;
//return (x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min;
}
@ -13,7 +18,7 @@ int fastMap(unsigned long x, int in_min, int in_max, int out_min, int out_max)
//This is a common case because it means converting from a standard 10-bit analog input to a byte or 10-bit analog into 0-511 (Eg the temperature readings)
//int fastMap1023toX(unsigned long x, int in_min, int in_max, int out_min, int out_max)
//removed ununsed variables, in_min and out_min is aways 0, in_max is aways 1023
int fastMap1023toX(unsigned long x, int out_max)
int fastMap1023toX(int x, int out_max)
{
return (x * out_max) >> 10;
}
@ -40,7 +45,7 @@ unsigned int divu10(unsigned int n)
int divs10(long n)
{
long q, r, p;
p = n + (n>>31 & 9);
p = n + ( (n>>31) & 9);
q = (p >> 1) + (p >> 2);
q = q + (q >> 4);
q = q + (q >> 8);
@ -94,7 +99,6 @@ inline long powint(int factor, unsigned int exponent)
{
long product = 1;
unsigned int counter = exponent;
while ( (counter--) > 0)
product *= factor;
while ( (counter--) > 0) { product *= factor; }
return product;
}