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//==========================================================================
//
//      var_misc.c
//
//      HAL implementation miscellaneous functions
//
//==========================================================================
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//==========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):    larsi
// Contributors:
// Date:         2007-07-09
// Purpose:      HAL miscellaneous functions
// Description:  This file contains miscellaneous functions provided by the
//               HAL.
//
//####DESCRIPTIONEND####
//
//========================================================================*/
 
#include <pkgconf/hal.h>
 
#include <cyg/infra/cyg_type.h>         // Base types
#include <cyg/infra/cyg_trac.h>         // tracing macros
#include <cyg/infra/cyg_ass.h>          // assertion macros
 
#include <cyg/hal/hal_intr.h>
 
#include <cyg/hal/hal_misc.h>
/*------------------------------------------------------------------------*/
// Array which stores the configured priority levels for the configured
// interrupts.
 
/* this may be useful later when interrupt masking of internal interrupt
   sources is implemented
 
volatile CYG_BYTE hal_interrupt_level[CYGNUM_HAL_ISR_COUNT];
*/
/*------------------------------------------------------------------------*/
 
void hal_variant_init(void)
{
}
 
//--------------------------------------------------------------------------
// Microsecond delay
// This uses reload timer 2, because timer 0 and 1 can cause DMA transfers
// and may be used by the application.
// Timer is initialized with 32 prescaler. If we need more precise delay
// this has to change.
 
void hal_delay_us(cyg_int32 n){
#define TIMER_TIME  CYGHWR_HAL_FR30_MB91301_SYSTEM_CLOCK_MHZ * 1000000 / CYGHWR_HAL_FR30_MB91301_CLKP_DIVIDER / 32
 
    unsigned int calc(unsigned long long n){
        return n * TIMER_TIME / 1000000;
    }
 
    cyg_uint16  timer_status;
 
    n = 21;//calc(n);
    // stop eventually running counter and initialize
    HAL_WRITE_UINT16(CYG_HAL_FR30_DLY_TMCSR, 0x812);
 
    HAL_WRITE_UINT16(CYG_HAL_FR30_DLY_TMRLR, 0xFFFF);
    while(n > 0xffff){
        // start counting
        HAL_WRITE_UINT16(CYG_HAL_FR30_DLY_TMCSR, 0x813);
        n = n - 0xffff;
        // look for underflow
        do {
            HAL_READ_UINT16(CYG_HAL_FR30_DLY_TMCSR, timer_status);
        } while (!(timer_status & BIT2));
        // clear underflow bit
        HAL_WRITE_UINT16(CYG_HAL_FR30_DLY_TMCSR, 0x813);
    }
    // clear count enable bit
    HAL_WRITE_UINT16(CYG_HAL_FR30_DLY_TMCSR, 0x810);
    // set new remaining count value
    HAL_WRITE_UINT16(CYG_HAL_FR30_DLY_TMRLR, n);
    // start counting
    HAL_WRITE_UINT16(CYG_HAL_FR30_DLY_TMCSR, 0x813);
    // look for underflow
    do {
        HAL_READ_UINT16(CYG_HAL_FR30_DLY_TMCSR, timer_status);
    } while (!(timer_status & BIT2));
    // clear underflow and count enable bits
    HAL_WRITE_UINT16(CYG_HAL_FR30_DLY_TMCSR, 0x810);
}
 
/*------------------------------------------------------------------------*/
/* End of var_misc.c                                                      */