SYNCDELAY

@syncdly.h

#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

#if( _SCYCL == 4 )

#define SYNCDELAY _nop_( ); \

                  _nop_( ); \

                  _nop_( ); \

                  _nop_( )

#endif

#if( _SCYCL == 5 )

#define SYNCDELAY _nop_( ); \

                  _nop_( ); \

                  _nop_( ); \

                  _nop_( ); \

                  _nop_( )

#endif

15.15 Synchronization Delay @TRM

Under certain conditions, some read and write accesses to EZ-USB registers must be separated by a synchronization delay.

The delay is necessary only under the following conditions:

■ Between a write to any register in the 0xE600-0xE6FF range and a write to one of the registers in Table 15-6.

■ Between a write to one of the registers in Table 15-6 and a read from any register in the 0xE600-0xE6FF range.