eCAP

The enhanced capture (eCAP) module, can be used in systems where accurate timing of external events is important. The eCAP module provides 6 eCAP channels, where one eCAP channel provides 4 x 32-bit time-stamp capture registers. eCAP channels also can be configured to provide a single-channel PWM output.
Each eCAP-Module (eCAP1-eCAP6) can only be used once.

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	Pin
eCAP1	GPIO5 / GPIO24 / GPIO34
eCAP2	GPIO7 / GPIO25
eCAP3	GPIO9 / GPIO26
eCAP4	GPIO11 / GPIO27
eCAP5	GPIO3 / GPIO48
eCAP6	GPIO1 / GPIO49

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Code example 1 (Capture mode)

In this example, eCAP1 is configured on GPIO24. As default, eCAPx is configured with an Interrupt-Service-Routine (ISR) that calculates the applied frequency on respective pin.

#include "global_defines.h"                                 //Include global_defines.h
#include "system_controls/system_controls.h"                //Include module of system controls
#include "ecap/ecap.h"                                      //Include module of eCAP
 
void main(void){
    int result = 0;                                         //Optional: can be used to check return values of functions
    int frequency_ecap = 0;   
    setSystemControls();                                    //Call setSystemControls() function
    result = init_eCAP(GPIO24);                             //Configures GPIO24 as eCAP pin. Returns result of operation
    while(1){                                               //Endless loop
        frequency_ecap = eCAP_getFrequency(GPIO24);         //Get frequency on GPIO24. Function returns frequency or negative value for invalid input-parameter or missing configuration  
    }
}

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Code example 2 (PWM mode)

An eCAP-Module can also be used to generate a PWM-signal with specific frequency and specific dutycycle on configured pin :

Min. frequency: 2 Hz
Max. frequency: 1 MHz

Min. dutycycle: 0
Max. dutycycle: 100

#include "global_defines.h"                                 //Include global_defines.h
#include "system_controls/system_controls.h"                //Include module of system controls
#include "ecap/ecap.h"                                      //Include module of eCAP
 
void main(void){
    int result = 0;                                         //Optional: can be used to check return values of functions
    setSystemControls();                                    //Call setSystemControls() function
    result = init_eCAP(GPIO24);                             //Configures GPIO24 as eCAP pin. Returns result of operation
    result = eCAP_pwmOutput(GPIO24, 10000, 50);             //Call function to generate a PWM-signal with frequency of 10 kHz and Dutycycle of 50 % on GPIO24. Returns result of operation
    while(1){
                                                            //Endless loop
    }
}

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Documented C-Code of module:

eCAP

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Detailed description in Technical Reference Manual:

Technical_Reference_Manual