#include <sam.h>

int main()
{
    PIOC->PIO_PDR = 1u << 25;
    PIOC->PIO_ABSR = 1u << 25; // select peripheral b

    // timer setup
    TC2->TC_CHANNEL[0].TC_CCR = TC_CCR_CLKDIS;               // Counter Clock Disable
    TC2->TC_CHANNEL[0].TC_CMR = TC_CMR_TCCLKS_TIMER_CLOCK1 | // Clock selected: internal MCK/2 clock signal (from PMC)
                                TC_CMR_LDRA_RISING |         // Load CV to RA when a rising edge on TIOA occurs
                                TC_CMR_LDRB_RISING |         // Load CV to RB when a rising edge on TIOA occurs (after ra loading occured)
                                TC_CMR_LDBSTOP;              // Counter clock is stopped when RB loading occurs.
    TC2->TC_CHANNEL[0].TC_CCR = TC_CCR_CLKEN;                // Counter Clock Enable

    // meassurements
    while (1)
    {
        TC2->TC_CHANNEL[0].TC_CCR = TC_CCR_SWTRG;       // software trigger
        while (~TC2->TC_CHANNEL[0].TC_SR & TC_SR_LDRBS) // wait until rb loading occurs
        {
        }
    }
}