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SysCtlClockGet returns strange frequency

Hello

I am just starting on moving code from Stellaris to Tiva and noticed something funny when setting the system clock on 4C129EN device.

ui32SysClock =

SysCtlClockFreqSet((SYSCTL_XTAL_25MHZ |

SYSCTL_OSC_MAIN |

SYSCTL_USE_PLL |

SYSCTL_CFG_VCO_480), 120000000);

sprintf(msg, "%ld - %ld", SysCtlClockGet(), ui32SysClock);

 

ui32SysClock correctly returns 120000000, SysCtlCLockGet returns 9600000

I was wondering why my timer was clocking much faster than I expected and traced this down the SysCtlClockGet fn.

// SysTickPeriodSet(SysCtlClockGet() / 100); // 10ms Tick goes very fast

SysTickPeriodSet(ui32SysClock / 100); // 10ms Tick is correct

Any reason why this should be the case?