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Hello,
why should we use below macro?
#define _IFREQ 24000 // IFCLK constant for Synchronization Delay
#define _CFREQ 48000 // CLKOUT constant for Synchronization Delay
in my application project,
IFCLK is 27mhz,should i use #define _IFREQ 27000 ?
and
i am not using clock out pin ,can i ignore this?
regards,
geetha.
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Hello Geetha,
These macro definitions are used for the calculation of the SYNCDELAY. You can refer to the syncdly.h file in the project folder where these values are used in the computation of the SYNCDELAY.
#define _SCYCL ( 3*(_CFREQ) + 5*(_IFREQ) - 1 ) / ( 2*(_IFREQ) )
#if( _SCYCL == 1 )
#define SYNCDELAY _nop_( )
#endif
#if( _SCYCL == 2 )
#define SYNCDELAY _nop_( ); \
_nop_( )
#endif
#if( _SCYCL == 3 )
#define SYNCDELAY _nop_( ); \
_nop_( ); \
_nop_( )
#endif
This macro definition does not affect the IFCLK/ CLKOUT frequency.
Best regards,
Srinath S
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Hello Geetha,
These macro definitions are used for the calculation of the SYNCDELAY. You can refer to the syncdly.h file in the project folder where these values are used in the computation of the SYNCDELAY.
#define _SCYCL ( 3*(_CFREQ) + 5*(_IFREQ) - 1 ) / ( 2*(_IFREQ) )
#if( _SCYCL == 1 )
#define SYNCDELAY _nop_( )
#endif
#if( _SCYCL == 2 )
#define SYNCDELAY _nop_( ); \
_nop_( )
#endif
#if( _SCYCL == 3 )
#define SYNCDELAY _nop_( ); \
_nop_( ); \
_nop_( )
#endif
This macro definition does not affect the IFCLK/ CLKOUT frequency.
Best regards,
Srinath S
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Hello shrinath,
I am asking you about syncdelay calculation.
in my project ,i am using 27MHZ IFCLK,
do i need to change these macros?that will effect syncdelay?
regards,
geetha
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Hello Geetha,
Yes, modifying these macros will affect the SYNCDELAY if you are using the same syncdly.h header file.
Best regards,
Srinath S
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Hello shrinath,
I am using 27mhz IFCLK,at this condition,can i use #define _IFREQ 48000 ?
or is it should be at #define _IFREQ 27000 ?
regards,
geetha.
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Hello Geetha,
It is not mandatory that the macro definition should be matching with the actual IFCLK frequency. The macro definition is only used for computing the SYNCDELAY. It would be logical if the _IFREQ macro definition matches the IFCLK but is not a mandatory condition.
Best regards,
Srinath S