
see http://mbed.org/users/no2chem/notebook/mbed-clock-control--benchmarks/
Diff: ClockControl/ClockControl.cpp
- Revision:
- 0:b5d3bd64d2dc
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/ClockControl/ClockControl.cpp Sun Jan 24 15:46:26 2010 +0000 @@ -0,0 +1,37 @@ +#include "ClockControl.h" + +void setPLL0Frequency(unsigned char clkSrc, unsigned short M, unsigned char N) +{ + LPC_SC->CLKSRCSEL = clkSrc; + LPC_SC->PLL0CFG = (((unsigned int)N-1) << 16) | M-1; + LPC_SC->PLL0CON = 0x01; + LPC_SC->PLL0FEED = 0xAA; + LPC_SC->PLL0FEED = 0x55; + while (!(LPC_SC->PLL0STAT & (1<<26))); + + LPC_SC->PLL0CON = 0x03; + LPC_SC->PLL0FEED = 0xAA; + LPC_SC->PLL0FEED = 0x55; +} + +void setPLL1Frequency(unsigned char clkSrc, unsigned short M, unsigned char N) +{ + LPC_SC->CLKSRCSEL = clkSrc; + LPC_SC->PLL1CFG = (((unsigned int)N-1) << 16) | M-1; + LPC_SC->PLL1CON = 0x01; + LPC_SC->PLL1FEED = 0xAA; + LPC_SC->PLL1FEED = 0x55; + while (!(LPC_SC->PLL1STAT & (1<<26))); + + LPC_SC->PLL1CON = 0x03; + LPC_SC->PLL1FEED = 0xAA; + LPC_SC->PLL1FEED = 0x55; +} + +unsigned int setSystemFrequency(unsigned char clkDivider, unsigned char clkSrc, unsigned short M, unsigned char N) +{ + setPLL0Frequency(clkSrc, M, N); + LPC_SC->CCLKCFG = clkDivider - 1; + SystemCoreClockUpdate(); + return SystemCoreClock; +} \ No newline at end of file