File content as of revision 0:eea8d19a7f6b:

#ifndef SENSORS_H
#define SENSORS_H
 
#define CHANNEL_0 0x00
#define CHANNEL_1 0x01
#define CHANNEL_2 0x02
#define CHANNEL_3 0x03
 
#define CPU_CLOCK 48000000
 
/**
*   Pulses sets how many edges to detect before returning a time, max of 2^16, affectively refers to sample time
*   Glitch filter recognizes change on input pin after 2^n rising clock edges
*   Setting glitch filter to zero disables glitch filter
*   TODO: DETERMINE EXACT FUNCTIONALITY AND USAFULNESS OF FUNCTION
*/
extern "C" void setup_counter(int glitch_filter);
 
/**
*   Measure the period observed on the sensor indicated by "sensor"
*   TO VERIFY (KL25Z):
*       PTC1 -> Pulse Counter Input 0 (00)
*       PTC2 -> Pulse Counter Input 1 (01)
*       PTC3 -> Pulse Counter Input 2 (10)
*       PTC4 -> Pulse Counter Input 3 (11)
*/
extern "C" int measure_clock_cycles(char sensor, int samples);
 
float measure_frequency(char sensor, int samples)
{
    // Divide the number of cpu clock cycles by the number of measured periods of the measured waveform to
    // get the number of clock cycles per period
    int clock_cycles = measure_clock_cycles(sensor, samples) / samples;
    
    // Divide CPU_CLOCK by the number of clock cycles to get the period
    return (CPU_CLOCK / (float)clock_cycles);  
}
 
#endif