2.55 Input Capture (ICAP)

Using The Library

In this application, a pulse signal is generated using the OCMP peripheral and is fed to the ICAP input. ICAP peripheral captures the time at every edge and displays the pulse width on the serial terminal.

uint16_t capturedValue[2];
volatile uint8_t captureIndex = 0;

int main ( void )
{
    /* Initialize all modules */
    SYS_Initialize ( NULL );
    
    ICAP1_Enable();
    
    OCMP3_Enable();
    
    TMR2_Start();
    
    while ( true )
    {
        /* Maintain state machines of all polled MPLAB Harmony modules. */
        SYS_Tasks ( );
        
        while(!ICAP1_CaptureStatusGet());

        capturedValue[captureIndex++] = ICAP1_CaptureBufferRead();

        if ( captureIndex > 1){
            printf("Pulse Width Count = %d\r\n",(capturedValue[1] - capturedValue[0]));
            captureIndex = 0;
        }
    }

    /* Execution should not come here during normal operation */

    return ( EXIT_FAILURE );
}

Library Interface

Input Capture peripheral library provides the following interfaces:

Functions

Data types and constants