Datasheet

www.ti.com

Application of the ECAP Module

32.3.2.1 Code Snippet for CAP Mode Absolute Time, Rising and Falling Edge Triggers

// Code snippet for CAP mode Absolute Time, Rising & Falling edge triggers

// Initialization Time

//=======================

// ECAP module 1 config

ECap1Regs.ECCTL1.bit.CAP1POL = EC_RISING;

ECap1Regs.ECCTL1.bit.CAP2POL = EC_FALLING;

ECap1Regs.ECCTL1.bit.CAP3POL = EC_RISING;

ECap1Regs.ECCTL1.bit.CAP4POL = EC_FALLING;

ECap1Regs.ECCTL1.bit.CTRRST1 = EC_ABS_MODE;

ECap1Regs.ECCTL1.bit.CTRRST2 = EC_ABS_MODE;

ECap1Regs.ECCTL1.bit.CTRRST3 = EC_ABS_MODE;

ECap1Regs.ECCTL1.bit.CTRRST4 = EC_ABS_MODE;

ECap1Regs.ECCTL1.bit.CAPLDEN = EC_ENABLE;

ECap1Regs.ECCTL1.bit.PRESCALE = EC_DIV1;

ECap1Regs.ECCTL2.bit.CAP_APWM = EC_CAP_MODE;

ECap1Regs.ECCTL2.bit.CONT_ONESHT = EC_CONTINUOUS;

ECap1Regs.ECCTL2.bit.SYNCO_SEL = EC_SYNCO_DIS;

ECap1Regs.ECCTL2.bit.SYNCI_EN = EC_DISABLE;

ECap1Regs.ECCTL2.bit.TSCTRSTOP = EC_RUN; // Allow TSCTR to run

// Run Time ( e.g. CEVT4 triggered ISR call)

//==========================================

TSt1 = ECap1Regs.CAP1; // Fetch Time-Stamp captured at t1

TSt2 = ECap1Regs.CAP2; // Fetch Time-Stamp captured at t2

TSt3 = ECap1Regs.CAP3; // Fetch Time-Stamp captured at t3

TSt4 = ECap1Regs.CAP4; // Fetch Time-Stamp captured at t4

Period1 = TSt3-TSt1; // Calculate 1st period

DutyOnTime1 = TSt2-TSt1; // Calculate On time

DutyOffTime1 = TSt3-TSt2; // Calculate Off time

1657

SPNU562–May 2014 Enhanced Capture (eCAP) Module

Submit Documentation Feedback