c6678 如何用csl初始化pll

各位专家好，我用的是c6678，想调整sysclk2 的频率，按照datasheet上的流程，自己写的pll程序运行之后发现dsp仿真时频率根本没有变化，不知道是哪个地方出了问题，还请各位老师指点一下 

CSL_PllcHandle  hPllc;

Uint8           goStatus;

 hPllc = CSL_PLLC_open (0);

CSL_PLLC_setPllCtrlPllEn (hPllc, 0);                            // Put PLLC in Bypass mode

CSL_PLLC_setPllCtrlPllEnSrc (hPllc, 0);                       // Enable PLLEN bit configuration

CSL_PLLC_setPllSecCtrlReg (hPllc, 0x10);                     //configure the SECCTL. 

CSL_PLLC_setPllCtrlPllPowerDown (hPllc, 1);               // Power down PLL

CSL_PLLC_setPllCtrlPllPowerDown (hPllc, 0);              // Wake up PLL

CSL_PLLC_setPllMultiplierCtrlReg (hPllc, 1);                             // Setup x1 multiplier rate

CSL_PLLC_setPllPreDivReg (hPllc, 1, 0);                    // Setup /1 divider rate and enable divider

CSL_PLLC_getPllStatusReg (hPllc, &goStatus);                         // Ensure no GO operation in progress already

while (goStatus != 0)
      {
         
          CSL_PLLC_getPllStatusReg (hPllc, &goStatus);                      // wait some time and recheck GOSTAT status
      }

CSL_PLLC_setPllDivReg (hPllc, 2,1, 0x40);                             // Setup /1 divider rate and enable divider 1

CSL_PLLC_setPllAlignCtrlReg (hPllc, 2);                                   // Set the respective ALNn bit in ALNCTL register

CSL_PLLC_setPllCmdReg (hPllc, 1);                                              // Start GO operation

CSL_PLLC_getPllStatusReg (hPllc, &goStatus);                                   // Ensure GO operation completes

 while (goStatus != 0)
      {
     
          CSL_PLLC_getPllStatusReg (hPllc, &goStatus);                                // wait some time and recheck GOSTAT status
      }

CSL_PLLC_setPllSecCtrlReg (hPllc, 0x00);                                //configure the SECCTL. 5th bit:BYPASS. 1-4bit:the od

CSL_PLLC_setPllCtrlPllEn (hPllc, 1);                                                        // Put PLLC back in PLL mode