Sliding Average for Boolean Inputs

slavg.c

/** 
    Sliding Average for Boolean Inputs
    
    Imagine you have a microcorntoler that can only do basic interger arithmetic.
    You want to ensure an input does not bounce. Normally you would use floating 
    point and division to maintain a sliding average, but we neither have 
    floating point values nore division on the given microcontoler.
    
    So intead a 8 bit integer is used as an average. If the input is up the 
    average is incremented and if the input id down decremented. To prevent 
    bounces at around half a basic hysteresis is aded.
    
    Now this function needs to be called over and over to gather and output the 
    current value. It may be usefull to tune the range of the average and 
    hysteresis to adjust your required timings. 
**/

BOOL in;
BOOL out;
BYTE avg;

void slavg()
{
    if (in == 1 && avg != 255)
        avg++;        
    if (in == 0 && avg != 0)
        avg--;        
    
    if (out == 1 && avg < 75)
        out = 0;
    if (out == 0 && avg > 180)
        out = 1;
}