// This file has been prepared for Doxygen automatic documentation generation.
/*! \file ********************************************************************
*
* Atmel Corporation
*
* - File              : main.c
* - Compiler          : IAR EWAAVR 2.28a/3.10c
*
* - Support mail      : avr@atmel.com
*
* - Supported devices : ATmega48/88/168
*
* - AppNote           : AVR444 - Sensorless control of three-phase brushless
*                       DC motors with ATmega48.
*
* - Description       : Example of how to use the ATmega48 for sensorless
*                       control of a three phase brushless DC motor.
*
* $Revision: 1.1 
* $Date: Monday, October 10, 2005 11:15:46 UTC 
*****************************************************************************/
/*
編譯器：GCC
CPU：ATMEGA128
頻率：4M
編譯平臺(tái)：VC++
程序流程：
主程序：
1. 端口初始化
   詳見P9頁
2. 定時(shí)器初始化
TC0:升序時(shí)，比較匹配發(fā)生時(shí)，OC0B清零，降序比較匹配發(fā)生時(shí)置位；相位修正PWM模式
    TOP值為OCR0A=200
TC1:8分頻
3. ADC初始化
參考電壓AREF；轉(zhuǎn)換結(jié)果左對齊
定時(shí)器/計(jì)數(shù)器0溢出觸發(fā)ADC自動(dòng)轉(zhuǎn)換
允許模擬比較器中斷（上升沿）
4. 換相控制數(shù)據(jù)表格
5. 首次換相輸出--共8次,然后打開TIMSK1的比較器A.
6. 全局中斷開,進(jìn)入循環(huán)
7.循環(huán)程序.

BMEF檢測的思路:
**進(jìn)入TC1的比較器A中斷,換相并復(fù)位換相定時(shí)器,設(shè)定HOLD-OFF定時(shí)器,打開TC1 的比較器B中斷;
打開TCO中斷,關(guān)閉TC1中斷,準(zhǔn)備零點(diǎn)檢測
**進(jìn)入TC0溢出中斷,取出ADC檢測的電壓值(周期中未通電相),根據(jù)上升或下降沿以及和標(biāo)定值比較判斷
是否為過零點(diǎn).
如果是過零點(diǎn),則對換相數(shù)據(jù)進(jìn)行處理,更新TC1的OCR1A,之后關(guān)閉TC0,打開TC1,轉(zhuǎn)入電流檢測通道,打開ADC轉(zhuǎn)換完成中斷.
如果不是過零點(diǎn),檢測電流過后,恢復(fù)到BMEF電壓檢測狀態(tài),打開ADC轉(zhuǎn)換完成中斷.(等待下一次TC0中斷)

*/
/*

疑問:
1.為何程序中多處出現(xiàn)清中斷標(biāo)志位命令:TIFRN.
2.看門狗的GCC中斷程序怎么寫
3.為了快速存取,在GCC中如何定義寄存器變量
IAR是這樣定義的.
__regvar __no_init volatile unsigned int filteredTimeSinceCommutation @14;
4.感覺過零點(diǎn)檢測失敗應(yīng)該恢復(fù)至定時(shí)器/計(jì)數(shù)器0溢出觸發(fā)ADC自動(dòng)轉(zhuǎn)換
  */
#include "BLDC.h"

#include <avr/io.h>
#include <avr/signal.h>
#include <avr/interrupt.h>

//! Array of power stage enable signals for each commutation step.
//驅(qū)動(dòng)功率管的信號(hào)組
unsigned char driveTable[6];

//! Array of ADC channel selections for each commutation step.
//ADC通道選擇組
unsigned char ADMUXTable[6];

//! Array holding the inter commutation delays used during startup.
unsigned int startupDelays[STARTUP_NUM_COMMUTATIONS];//8 啟動(dòng)期間的變換次數(shù)

/*! \brief Filtered commutation timer variable and speed indicator.
 *  This value equals half the time of one commutation step. It is filtered
 *  through an IIR filter, so the value stored is not the most recent measuremnt.
 *  The variable is stored in registers R14-R15 for quicker access.
 */
//該變量數(shù)值為變換步階時(shí)間的一半，是通過IIR得出的。所以儲(chǔ)存的值不是最新測量的數(shù)值
//為了快速存取，將這個(gè)變量被放入R14，R15寄存器中
//__regvar __no_init volatile unsigned int filteredTimeSinceCommutation @14;
volatile unsigned int filteredTimeSinceCommutation;
/*! \brief The power stage enable signals that will be output to the motor drivers
 *  at next commutation.
 *
 *  This variable holds the pattern of enable signals that will be output to the
 *  power stage at next commutation. It is stored in register R13 for quick access.
 */
//該變量為下一時(shí)刻功率管的驅(qū)動(dòng)信號(hào)
//為了快速存取，將這個(gè)變量被放入R13寄存器中
//__regvar __no_init volatile unsigned char nextDrivePattern @13;
volatile unsigned char nextDrivePattern;
/*! \brief Polarity of the expected zero crossing.
 *
 *  The polarity of the expected zero crossing.
 *  Could be eiter \ref EDGE_FALLING or \ref EDGE_RISING.
 */
//過零點(diǎn)的斜率（極性）
//為了快速存取，將這個(gè)變量被放入R12寄存器中
//__regvar __no_init volatile unsigned char zcPolarity @ 12;
volatile unsigned char zcPolarity;
/*! \brief The commutation step that starts at next commutation.
 *
 *  The commutation step that starts at next commutation. This is used to keep
 *  track on where in the commutation cycle we are. Stored in register R11 for
 *  quick access
 */
//下一個(gè)變換步階，用于追蹤現(xiàn)在所處的位置
//為了快速存取，將這個(gè)變量被放入R11寄存器中
//__regvar __no_init volatile unsigned char nextCommutationStep @11;
volatile unsigned char nextCommutationStep;
//! ADC reading of external analog speed reference.
//外部速度比較輸入信號(hào)
volatile unsigned char speedReferenceADC;

//! ADC reading of shunt voltage.
//外部分壓輸入信號(hào)
volatile unsigned char shuntVoltageADC = 0;

//! ADC reading of the known external reference voltage.
//外部參考電壓輸入信號(hào)
volatile unsigned char referenceVoltageADC;

//! Flag that specifies whether a new external speed reference 
//! and a motor speed measurement is available.
//速度量測結(jié)束標(biāo)志
volatile unsigned char speedUpdated = FALSE;

//! Flag that specifies whether a new current measurement is available.
// 電流量測結(jié)束標(biāo)志
volatile unsigned char currentUpdated = FALSE;


/*! \brief Program entry point.
 *
 *  Main initializes all peripheral units used and calls the startup procedure.
 *  All commutation control from that point is done in interrupt routines.
 */
void main(void)
{
  // Initialize all sub-systems.
  //ResetHandler();
  InitPorts();
  InitTimers();
  InitADC();
  MakeTables();
  InitAnalogComparator();

  // Run startup procedure.
  StartMotor();

  // Turn on watchdog for stall-detection.
  //WatchdogTimerEnable();
  //__enable_interrupt();
  sei();
  for(;;)
  {
    PWMControl();
  }
}


/*! \brief Examines the reset source and acts accordingly.
 *
 *  This function is called early in the program to disable watchdog timer and
 *  determine the source of reset.
 *
 *  Actions can be taken, based on the reset source. When the watchdog is used as
 *  stall protection, a stall can be detected here. It is possible to e.g. store
 *  a variable in EEPROM that counts the number of failed restart attempts. After a
 *  certain number of attempts, the motor could simply refuse to continue until
 *  an external action happens, indicating that the rotor lock situation could be
 *  fixed.
 */
//將啟動(dòng)失敗的嘗試次數(shù)寫入EEPROM，達(dá)到一定次數(shù)禁止啟動(dòng)，等待處理。
/*static void ResetHandler(void)
{
  __eeprom unsigned static int restartAttempts;
  // Temporary variable to avoid unnecessary reading of volatile register MCUSR.
  unsigned char tempMCUSR;

  tempMCUSR = MCUSR;
  MCUSR = tempMCUSR & ~((1 << WDRF) | (1 << BORF) | (1 << EXTRF) | (1 << PORF));

  // Reset watchdog to avoid false stall detection before the motor has started.
  __disable_interrupt();
  __watchdog_reset();
  WDTCSR |= (1 << WDCE) | (1 << WDE);
  WDTCSR = 0x00;

  // Examine the reset source and take action.
  switch (tempMCUSR & ((1 << WDRF) | (1 << BORF) | (1 << EXTRF) | (1 << PORF)))
  {
  case (1 << WDRF):
    restartAttempts++;
    if (restartAttempts >= MAX_RESTART_ATTEMPTS)
    {
      // Do something here. E.g. wait for a button to be pressed.
	//可在此輸入處理 程序，比如按鍵解除。
      for (;;)
      {

      }
    }

    // Put watchdog reset handler here.
    break;
  case (1 << BORF):
    //Put brownout reset handler here.
    break;
  case (1 << EXTRF):
    restartAttempts = 0;
    // Put external reset handler here.
    break;
  case (1 << PORF):
    restartAttempts = 0;
    // Put power-on reset handler here.
    break;
  }
}
*/

/*! \brief Initializes I/O ports.
 *
 *  Initializes I/O ports.
 */

static void InitPorts(void)
{
  // Init DRIVE_DDR for motor driving.
  DRIVE_DDR = (1 << UL) | (1 << UH) | (1 << VL) | (1 << VH) | (1 << WL) | (1 << WH);
  //DDRB=0b00111111;
  // Init PORTD for PWM on PD5.
  DDRD = (1 << PD5);
  //DDRD=0b00100000;
  // Disable digital input buffers on ADC channels.
  //關(guān)閉ADC輸入數(shù)字緩沖器
  DIDR0 = (1 << ADC4D) | (1 << ADC3D) | (1 << ADC2D) | (1 << ADC1D) | (1 << ADC0D);
  //DIDR0=0b00011111;
}


/*! \brief Initializes timers (for commutation timing and PWM).
 *
 *  This function initializes Timer/counter0 for PWM operation for motor speed control
 *  and Timer/counter1 for commutation timing.
 */
static void InitTimers(void)
{
  // Set up Timer/counter0 for PWM, output on OCR0B, OCR0A as TOP value, prescaler = 1.
  //比較匹配A不與OC0A連接
  //TCCROA=0x;//升序時(shí)，比較匹配發(fā)生時(shí)，OC0B清零，降序比較匹配發(fā)生時(shí)置位；相位修正PWM模式。
  TCCR0A = (0 << COM0A1) | (0 << COM0A0) | (1 << COM0B1) | (0 << COM0B0) | (0 << WGM01) | (1 << WGM00);
  TCCR0B = (1 << WGM02) | (0 << CS02) | (0 << CS01) | (1 << CS00);//CLK 無分頻
  OCR0A = PWM_TOP_VALUE;//8m/20k/2=200 設(shè)置TOP值（TOP=OCR0A）
  TIFR0 = TIFR0;//意義何在？
  TIMSK0 = (0 << TOIE0);//TC0溢出中斷禁止

  // Set up Timer/counter1 for commutation timing, prescaler = 8.
  TCCR1B = (1 << CS11) | (0 << CS10);//為何沒有把CS12加進(jìn)去？
}


/*! \brief Initializes the AD-converter.
 *
 *  This function initializes the AD-converter and makes a reading of the external
 *  reference voltage.
 */
static void InitADC(void)
{
  // First make a measurement of the external reference voltage.
  //參考電壓AREF；轉(zhuǎn)換結(jié)果左對齊；選取電源通道5
  ADMUX = ADMUX_REF_VOLTAGE;//  ((0 << REFS1) | (0 << REFS0))|(1<<ADLAR)|0X05;
  //ADC使能；ADC開始轉(zhuǎn)換；讀出電源電壓                         
  ADCSRA = (1 << ADEN) | (1 << ADSC) | (1 << ADIF) | (ADC_PRESCALER_16);
  while (ADCSRA & (1 << ADSC))
  {

  }
  referenceVoltageADC = ADCH;//讀入VCC電壓值

  // Initialize the ADC for autotriggered operation on PWM timer overflow.
  //ADC使能|ADC開始轉(zhuǎn)換禁止|自動(dòng)觸發(fā)使能|清中斷標(biāo)志|ADC中斷禁止
  ADCSRA = (1 << ADEN) | (0 << ADSC) | (1 << ADATE) | (1 << ADIF) | (0 << ADIE) | ADC_PRESCALER_8;
  //定時(shí)器/計(jì)數(shù)器0溢出觸發(fā)ADC轉(zhuǎn)換
  ADCSRB = ADC_TRIGGER_SOURCE;
  
}


/*! \brief Initializes the analog comparator.
 *
 *  This function initializes the analog comparator for overcurrent detection.
 */
static void InitAnalogComparator(void)
{
#ifdef ANALOG_COMPARATOR_ENABLE
  // Enable analog comparator interrupt on rising edge.
  //允許模擬比較器中斷（上升沿）
  ACSR = (0 << ACBG) | (1 << ACI) | (1 << ACIE) | (1 << ACIS1) | (1 << ACIS0);
#endif
}


/*! \brief Initializes the watchdog timer
 *
 *  This function initializes the watchdog timer for stall restart.
 */
/*static void WatchdogTimerEnable(void)
{
  __disable_interrupt();
  __watchdog_reset();

  WDTCSR |= (1 << WDCE) | (1 << WDE);

  WDTCSR = (1 << WDIF) | (1 << WDIE) | (1 << WDE) | (1 << WDP2);
  __enable_interrupt();
}
*/

/*! \brief Initializes arrays for motor driving and AD channel selection.
 *
 *  This function initializes the arrays used for motor driving and AD channel
 *  selection that changes for each commutation step.
 */
static void MakeTables(void)
{
#if DIRECTION_OF_ROTATION == CCW//如果定義了方向?yàn)镃CW，則執(zhí)行CCW程序。
  driveTable[0] = DRIVE_PATTERN_STEP1_CCW;//UY
  driveTable[1] = DRIVE_PATTERN_STEP2_CCW;//UW
  driveTable[2] = DRIVE_PATTERN_STEP3_CCW;//YW
  driveTable[3] = DRIVE_PATTERN_STEP4_CCW;//YU
  driveTable[4] = DRIVE_PATTERN_STEP5_CCW;//WY
  driveTable[5] = DRIVE_PATTERN_STEP6_CCW;//WY

  ADMUXTable[0] = ADMUX_W;
  ADMUXTable[1] = ADMUX_V;
  ADMUXTable[2] = ADMUX_U;
  ADMUXTable[3] = ADMUX_W;
  ADMUXTable[4] = ADMUX_V;
  ADMUXTable[5] = ADMUX_U;
#else
  driveTable[0] = DRIVE_PATTERN_STEP1_CW;
  driveTable[1] = DRIVE_PATTERN_STEP2_CW;
  driveTable[2] = DRIVE_PATTERN_STEP3_CW;
  driveTable[3] = DRIVE_PATTERN_STEP4_CW;
  driveTable[4] = DRIVE_PATTERN_STEP5_CW;
  driveTable[5] = DRIVE_PATTERN_STEP6_CW;

  ADMUXTable[0] = ADMUX_U;
  ADMUXTable[1] = ADMUX_V;
  ADMUXTable[2] = ADMUX_W;
  ADMUXTable[3] = ADMUX_U;
  ADMUXTable[4] = ADMUX_V;
  ADMUXTable[5] = ADMUX_W;

#endif

  startupDelays[0] = 200;//啟動(dòng)延時(shí)數(shù)組附值
  startupDelays[1] = 150;
  startupDelays[2] = 100;
  startupDelays[3] = 80;
  startupDelays[4] = 70;
  startupDelays[5] = 65;
  startupDelays[6] = 60;
  startupDelays[7] = 55;
}


/*! \brief Executes the motor startup sequence.
 *
 *  This function locks the motor into a known position and fires off a
 *  commutation sequence controlled by the Timer/counter1 overflow interrupt.
 */
static void StartMotor(void)
{
  unsigned char i;
  //OCR0B =130；TOP=OCR0A=200--在定時(shí)器初始化中定義
  SET_PWM_COMPARE_VALUE(STARTUP_PWM_COMPARE_VALUE);

  nextCommutationStep = 0;

  //Preposition.
  DRIVE_PORT = driveTable[nextCommutationStep];
  StartupDelay(STARTUP_LOCK_DELAY);//第一次變換持續(xù)時(shí)間
  nextCommutationStep++;
  nextDrivePattern = driveTable[nextCommutationStep];

  for (i = 0; i < STARTUP_NUM_COMMUTATIONS; i++)
  {
    DRIVE_PORT = nextDrivePattern;
    StartupDelay(startupDelays[i]);
    //參考電壓VREF，左對齊，選取零點(diǎn)檢測通道
    ADMUX = ADMUXTable[nextCommutationStep];

    // Use LSB of nextCommutationStep to determine zero crossing polarity.
    zcPolarity = nextCommutationStep & 0x01;//大概是判斷零點(diǎn)斜率

    nextCommutationStep++;
    if (nextCommutationStep >= 6)
    {
      nextCommutationStep = 0;
    }
    nextDrivePattern = driveTable[nextCommutationStep];
  }

  // Switch to sensorless commutation.
  // 啟動(dòng)結(jié)束，進(jìn)入無傳感器模式正常運(yùn)行
  TCNT1 = 0;
  //輸出比較匹配A中斷使能,行使換相功能，復(fù)位換相定時(shí)器，啟動(dòng)HOLD-OFF準(zhǔn)備定時(shí)比較器
  TIMSK1 = (1 << OCIE1A);

  // Set filteredTimeSinceCommutation to the time to the next commutation.
  filteredTimeSinceCommutation = startupDelays[STARTUP_NUM_COMMUTATIONS - 1] * (STARTUP_DELAY_MULTIPLIER  / 2);
  //不清楚其含義
}


/*! \brief Timer/counter0 bottom overflow. Used for zero-cross detection.
 *
 *  This interrupt service routine is called every time the up/down counting
 *  PWM counter reaches bottom. An ADC reading on the active channel is
 *  automatically triggered at the same time as this interrupt is triggered.
 *  This is used to detect a zero crossing.
 *
 *  In the event of a zero crossing, the time since last commutation is stored
 *  and Timer/counter1 compare A is set up to trigger at the next commutation
 *  instant.
 */
//當(dāng)PWM計(jì)數(shù)器歸零時(shí)引起中斷，同時(shí)觸發(fā)AD轉(zhuǎn)換，零點(diǎn)檢測服務(wù)程序
SIGNAL(SIG_OVERFLOW1)
{
  unsigned char temp;

  // Disable ADC auto-triggering. This must be done here to avoid wrong channel being sampled on manual samples later.
  //ADC自動(dòng)觸發(fā)禁止；ADC中斷禁止，開始手動(dòng)轉(zhuǎn)換
  ADCSRA &= ~((1 << ADATE) | (1 << ADIE));
  
  // Wait for auto-triggered ADC sample to complete.
  
  while (!(ADCSRA & (1 << ADIF)))
  {// 等待自動(dòng)ADC采樣結(jié)束
  
	  }
  temp = ADCH;
  if (((zcPolarity == EDGE_RISING) && (temp > ADC_ZC_THRESHOLD)) || ((zcPolarity == EDGE_FALLING) && (temp < ADC_ZC_THRESHOLD)))
  {//上升沿且檢測點(diǎn)電壓高于設(shè)定零點(diǎn)極限電壓或處在下降沿且低于零點(diǎn)極限電壓時(shí)
    unsigned int timeSinceCommutation;