[参考译文] SM320F28335-HT：SM320F28335-HT

Fred、

谢谢、闪存 WS 应该可以、从100MHz (20MHz X -塔)变为105MHz (30MHz)都需要 WS=3、因此这不需要改变。

您能否确认是否正在使用 sysctrl.c 中的 InitPLL()函数来设置 PLL？  这更适合我确认这里的操作顺序。

您在30MHz X 直流转换器中看到的任何器件行为、例如、请参阅 XRSn 脉冲或任何有关代码在引导流程中可能已进入的位置的指示？

void 
InitPll(Uint16 val, Uint16 divsel)
{
    //
    // Make sure the PLL is not running in limp mode
    //
    if (SysCtrlRegs.PLLSTS.bit.MCLKSTS != 0)
    {
        //
        // Missing external clock has been detected
        // Replace this line with a call to an appropriate
        // SystemShutdown(); function.
        //
        asm("        ESTOP0");
    }

    //
    // DIVSEL MUST be 0 before PLLCR can be changed from
    // 0x0000. It is set to 0 by an external reset XRSn
    // This puts us in 1/4
    //
    if (SysCtrlRegs.PLLSTS.bit.DIVSEL != 0)
    {
        EALLOW;
        SysCtrlRegs.PLLSTS.bit.DIVSEL = 0;
        EDIS;
    }

    //
    // Change the PLLCR
    //
    if (SysCtrlRegs.PLLCR.bit.DIV != val)
    {
        EALLOW;
        
        //
        // Before setting PLLCR turn off missing clock detect logic
        //
        SysCtrlRegs.PLLSTS.bit.MCLKOFF = 1;
        SysCtrlRegs.PLLCR.bit.DIV = val;
        EDIS;

        //
        // Optional: Wait for PLL to lock.
        // During this time the CPU will switch to OSCCLK/2 until
        // the PLL is stable.  Once the PLL is stable the CPU will
        // switch to the new PLL value.
        //
        // This time-to-lock is monitored by a PLL lock counter.
        //
        // Code is not required to sit and wait for the PLL to lock.
        // However, if the code does anything that is timing critical,
        // and requires the correct clock be locked, then it is best to
        // wait until this switching has completed.
        //

        //
        // Wait for the PLL lock bit to be set.
        //

        //
        // The watchdog should be disabled before this loop, or fed within
        // the loop via ServiceDog().
        //

        //
        // Uncomment to disable the watchdog
        //
        DisableDog();

        while(SysCtrlRegs.PLLSTS.bit.PLLLOCKS != 1)
        {
            //
            // Uncomment to service the watchdog
            //
            //ServiceDog();
        }

        EALLOW;
        SysCtrlRegs.PLLSTS.bit.MCLKOFF = 0;
        EDIS;
    }

    //
    // If switching to 1/2
    //
    if((divsel == 1)||(divsel == 2))
    {
        EALLOW;
        SysCtrlRegs.PLLSTS.bit.DIVSEL = divsel;
        EDIS;
    }

    //
    // NOTE: ONLY USE THIS SETTING IF PLL IS BYPASSED (I.E. PLLCR = 0) OR OFF
    // If switching to 1/1
    // * First go to 1/2 and let the power settle
    //   The time required will depend on the system, this is only an example
    // * Then switch to 1/1
    //
    if(divsel == 3)
    {
        EALLOW;
        SysCtrlRegs.PLLSTS.bit.DIVSEL = 2;
        DELAY_US(50L);
        SysCtrlRegs.PLLSTS.bit.DIVSEL = 3;
        EDIS;
    }
}