tms320C6747 PLL配置问题

void InitPLL(void)
{
    int i = 0;

    Uint8 CLKMODE = 1;    //方波
    Uint8 PLLM = 19;    //25*(19+1)=500M
    Uint8 POSTDIV = 1;  // clk_M / 2 = 250M
    Uint8 PLLDIV2 = 1;
    Uint8 PLLDIV3 = 2;    //250/3=83M
    Uint8 PLLDIV5 = 5;
    Uint8 PLLDIV7 = 7;
    Uint8 PREDIV = 0;

    PLL0_PLLCTL &=  0xFFFFFFFE;

   for(i=0; i<PLLEN_MUX_SWITCH; i++) {;}

    PLL0_PLLCTL &= 0xFFFFFEFF;
    PLL0_PLLCTL |= (CLKMODE<<8);


    PLL0_PLLCTL &=  0xFFFFFFDF;
    PLL0_PLLCTL &=  0xFFFFFDFF;
    PLL0_PLLCTL &= 0xFFFFFFF7;
    PLL0_PLLCTL |= 0x10;
    PLL0_PLLCTL &= 0xFFFFFFFD;
    PLL0_PLLCTL &= 0xFFFFFFEF;

    PLL0_PREDIV = 0x8000 | PREDIV;

    PLL0_PLLM = PLLM; /* Make PLLMULTIPLEIR as bootpacket*/

    PLL0_POSTDIV = 0x8000 | POSTDIV; /* Make POSTDIV as bootpacket*/

    while(PLL0_PLLSTAT & 0x1==1){}

    PLL0_PLLDIV2 = 0x8000 | PLLDIV2;

    PLL0_PLLDIV3 = 0x8000 | PLLDIV3; /* Make PLLDIV3 as bootpacket, do it for other PLLDIVx to if required*/
    PLL0_PLLDIV5 = 0x8000 | PLLDIV5; /* Make PLLDIV5 as bootpacket, do it for other PLLDIVx to if required*/
    PLL0_PLLDIV7 = 0x8000 | PLLDIV7; /* Make PLLDIV7 as bootpacket, do it for other PLLDIVx to if required*/


    PLL0_PLLCMD |= 0x1;

    while(PLL0_PLLSTAT & 0x1==1) { }

    PLL0_PLLCTL |= 0x8;

    for(i=0; i<PLL_LOCK_TIME_CNT; i++) {;}

    PLL0_PLLCTL |=  0x1;

    KICK0R = 0x83e70b13;  // Kick0 register + data (unlock)
    KICK1R = 0x95a4f1e0;  // Kick1 register + data (unlock)
}