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Quad Timer ,I/O

Started by praveen August 9, 2004
Hi

I am looking for a help in Quad timers (DSp56f801)

My questions are: 1. Is it that we have to declare explicitly the Quad timers pins as
output pins in order to get the output or is it ok with outputDisabled
Parameter as 1. I use quad timer D2.

const qtsState quadParam1 =
{

/* Mode = */ qtCount,
/* InputSource = */ qtPrescalerDiv1,
/* InputPolarity = */ qtNormal,
/* SecondaryInputSource = */ 0,

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

/* OutputMode = */ qtToggleOnCompare,
/* OutputPolarity = */ qtNormal,
/* OutputDisabled = */ 1,

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

/* CaptureMode = */ qtDisabled,

/* CompareValue1 = */ 0x00B5,
/* CompareValue2 = */ 0,
/* InitialLoadValue = */ 0x0000,

/* CallbackOnCompare = */ {0, 0 },
/* CallbackOnOverflow = */ { 0, 0 },
/* CallbackOnInputEdge = */ { 0, 0 }}; What will be its output .From the datasheet I read the o/p is the
OFLAG signal.

2.Can you give the specifications for this signal like its voltage
level and time durations.

3.From the data sheet it says we can generate square waveforms using
this OFLAG signal. Can anyone give me an example .

Thanks
Praveen



Hi Praveen,

You will need to have /* OutputDisabled = */ 0, //FALSE is enabled.

Also the other thing you need is to include the following in the
appconfig.h file to enable the timer when using the SDK.
#define INCLUDE_USER_TIMER_D_2 0

Your waveform should have about a 3.3v level and with the settings
should toggle every 4.525 microseconds (with an 80MHz clk) for a
waveform frequency of 110.497kHz give-or-take-a-little (I can never
quite tell with the quad timers unless I use an oscope).

Pete

--- In , "praveen" <powerarm2001@y...>
wrote:
> Hi
>
> I am looking for a help in Quad timers (DSp56f801)
>
> My questions are: > 1. Is it that we have to declare explicitly the Quad timers pins
as
> output pins in order to get the output or is it ok with
outputDisabled
> Parameter as 1. I use quad timer D2.
>
> const qtsState quadParam1 =
> {
>
> /* Mode = */ qtCount,
> /* InputSource = */ qtPrescalerDiv1,
> /* InputPolarity = */ qtNormal,
> /* SecondaryInputSource = */ 0,
>
> /* CountFrequency = */ qtRepeatedly,
> /* CountLength = */ qtUntilCompare,
> /* CountDirection = */ qtUp,
>
> /* OutputMode = */ qtToggleOnCompare,
> /* OutputPolarity = */ qtNormal,
> /* OutputDisabled = */ 1,
>
> /* Master = */ 0,
> /* OutputOnMaster = */ 0,
> /* CoChannelInitialize = */ 0,
> /* AssertWhenForced = */ 0,
>
> /* CaptureMode = */ qtDisabled,
>
> /* CompareValue1 = */ 0x00B5,
> /* CompareValue2 = */ 0,
> /* InitialLoadValue = */ 0x0000,
>
> /* CallbackOnCompare = */ {0, 0 },
> /* CallbackOnOverflow = */ { 0, 0 },
> /* CallbackOnInputEdge = */ { 0, 0 }}; > What will be its output .From the datasheet I read the o/p is the
> OFLAG signal.
>
> 2.Can you give the specifications for this signal like its voltage
> level and time durations.
>
> 3.From the data sheet it says we can generate square waveforms using
> this OFLAG signal. Can anyone give me an example .
>
> Thanks
> Praveen