whisper/SHA_TimeUtilsLoop.c

// Copyright (c) 2010, Atmel Corporation.
// All rights reserved.
//
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// modification, are permitted provided that the following conditions are met:
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//       names of its contributors may be used to endorse or promote products
//       derived from this software without specific prior written permission.
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
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#include <stdint.h>
#include "SHA_TimeUtils.h"


// The values below are valid for an AVR 8-bit processor running at 16 MHz.
// Code is compiled with -O1.

//!< Offsets time needed to prepare microseconds loop.
#define SHA_TIME_OFFSET_US      (7)

//!< Fill a while loop with these CPU instructions to achieve 1 us per iteration.
#define SHA_TIME_LOOP_FILLER    asm volatile ("nop\n\tnop\n\tnop\n\tnop\n\tnop\n\tnop\n\tnop")


extern void SA_Delay(uint32_t delay);






/** \brief Delays for a certain amount of time.
 *
 * \param[in] delay Delay for this number of microseconds (us).
 */
void SHAP_Delay(uint32_t delay) {
    if (delay <= SHA_TIME_OFFSET_US)
        // We spent already this much time entering this function.
        // With other words: A value <= SHA_TIME_OFFSET_US will not produce the desired delay.
        return;

    delay -= SHA_TIME_OFFSET_US;


    SA_Delay(delay);

    return;
}


void loop_delay(int8_t multp) {
    int i, base = 2000000 *multp;
    for(i=0;i<base;i++) {
        double value = 10.0; //((i * 33.3) - 12.1) / 10.0;
        value += 1.0;
    }
}