[업무일지]20101004-임종현

@Lowlevel.c@

void lowlevel_init(void)           //16line 선택적 컴파일
{
    unsigned char i = 0;

    ///////////////////////////////////////////////////////////////////////////
    // EFC Init
    ///////////////////////////////////////////////////////////////////////////
#ifdef AT91SAM7S512     //선택적 컴파일--AT91SAM7S512가 define(정의)되면 밑에 두줄을 포함한다..
    AT91C_BASE_MC->MC0_FMR = AT91C_MC_FWS_1FWS; // 1 Wait State to work at 48MHz
    AT91C_BASE_MC->MC1_FMR = AT91C_MC_FWS_1FWS; // 1 Wait State to work at 48MHz
#else                            //선택적 컴파일--AT91SAM7S512가 define(정의)되지않으면 밑에 한줄을 포함한다..
    AT91C_BASE_MC->MC_FMR = AT91C_MC_FWS_1FWS; // 1 Wait State to work at 48MHz
//AT91C_MC_FWS_1FWS => #define  AT91C_MC_FWS_1FWS                 (0x1 <<  8) // (MC) 2 cycles for Read, 3 for Write operations
//★MC_FMR : MC Flash Mode Register

Flash를 읽거나 쓸때 걸리는 속도

AT91C_BASE_MC = 0xFFFFFF00이며 
MC_FMR은 MC에서 0ㅌ60만큼  떨어져 있다. 그래서 결국 0XFFFFFF60과 같다.

AT91_BASE_MC -> MC_FMR =value;
(volatile unsigned int*) 0xFFFFFF=value;
AT91C_MC_FMR(AT91_CAST(AT91_REG *)주소값 = value;
*AT91C_MC_FMR = value;


#endif
    ///////////////////////////////////////////////////////////////////////////
    // Init PMC Step 1. Enable Main Oscillator
    // Main Oscillator startup time is board specific:
    // Main Oscillator Startup Time worst case (3MHz) corresponds to 15ms
    // (0x40 for AT91C_CKGR_OSCOUNT field)
    ///////////////////////////////////////////////////////////////////////////
    AT91C_BASE_PMC->PMC_MOR = (((AT91C_CKGR_OSCOUNT & (0x40 << 8)) | AT91C_CKGR_MOSCEN));
  
// ★PMC_MOR

// Wait Main Oscillator stabilization
//main Oscillator가 안정될때까지 대기
    while (!(AT91C_BASE_PMC->PMC_SR & AT91C_PMC_MOSCS));

(#은 전처리 지시어)


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@makefile@
CCFLAGS=-g -mcpu=arm7tdmi $(OPTIM) -Wall -I$(WCINCL) -D$(WCTARGET)