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Reloading of on off time for quad timer for PWM mode.

Started by Nitin Madhukar Yewale January 28, 2003

Hi,

I have an application for 56F827 processor, in which I am using
Quad timer in PWM mode. On and off time for PWM mode of Quad timer will
change according to the input (Dynamically).

I have initialized quad timer as follows:-

************************************************************************
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qt_sState quadParam1 = {
/* Mode = */ qtVariableFreqPWM,
/* InputSource = */ qtPrescalerDiv64,
/* InputPolarity = */ qtNormal,
/* SecondaryInputSource = */ 0,

/* CountFrequency = */ qtRepeatedly,
/* CountLength = */ qtUntilCompare,
/* CountDirection = */ qtUp,

/* OutputMode = */ qtToggleUsingAlternateCompare,
#ifdef ACTIVE_LOW
/* OutputPolarity = */ qtInverted,//qtNormal,
#else
/* OutputPolarity = */ qtNormal,
#endif
/* OutputDisabled = */ 0,

/* Master = */ 0,
/* OutputOnMaster = */ 0,
/* CoChannelInitialize = */ 0,
/* AssertWhenForced = */ 0,

/* CaptureMode = */ qtDisabled,

/* CompareValue1 = */ 0x000f, // Off Time
/* CompareValue2 = */ 0xf414, // On Time
/* InitialLoadValue = */ 0x0000,

/* CallbackOnCompare = */ { CallbackOnCompare1, 0 },
/* CallbackOnOverflow = */ { 0, 0 },
/* CallbackOnInputEdge = */ { 0, 0 },
0, //ComparatorValue2;
0, //ComparatorValue1;
0,//qtEnableCompareInterrupt, //InterruptEnable2 : 1;
0,//qtDisableCompareInterrupt, //InterruptEnable1 : 1;
qtLoadOnCompare2, //LoadControl2 : 2;
qtLoadOnCompare1 //LoadControl1 : 2;
};
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But ComparatorValue2 & ComparatorValue1 values are 0, assigning
them after getting the input.

I am writing those values by using following funcion qtIoctl (TimerQ1, QT_LOAD_COMPARATOR_LOAD_REG1, Main_Off_Cnt,
BSP_DEVICE_NAME_QUAD_TIMER_A_0);
qtIoctl (TimerQ1, QT_LOAD_COMPARATOR_LOAD_REG2, Main_On_Cnt,
BSP_DEVICE_NAME_QUAD_TIMER_A_0); Though I have intialized timer such that new values of on and
off time will be loaded into the registers and will be effective from
that instant I can't see expected change on the timer output.

Am I missing any initialization?

Regards,
Nitin

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