ClockControl

Published 24 Jan 2010, by Michael Wei
clock, control, frequency
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main.cpp

00001 #include "mbed.h"
00002 #include "ClockControl/ClockControl.h"
00003 #include "CoreMark/core_portme.h"
00004 
00005 int main() {
00006     while(1) {   
00007     
00008 
00009     printf("mbed Clock Control test\r\n");
00010     printf("(c) 2010 Michael Wei\r\n");
00011     
00012     unsigned short newM = 12;
00013     unsigned short newN = 1;
00014     
00015     printf("Value of M? (default = 12):\r\n");
00016     scanf("%d", &newM);
00017     
00018     printf("Value of N? (default = 1):\r\n");
00019     scanf("%d", &newN);
00020     
00021     setSystemFrequency(0x3, 0x1, newM, newN);
00022     
00023     Serial pc(USBTX, USBRX); // tx, rx
00024     
00025     //This code by Simon Ford: http://mbed.org/forum/mbed/topic/229/?page=1#comment-1225
00026     
00027     int Fin = 12000000; // 12MHz XTAL
00028     pc.printf("PLL Registers:\r\n");
00029     pc.printf(" - PLL0CFG = 0x%08X\r\n", LPC_SC->PLL0CFG);
00030     pc.printf(" - CLKCFG  = 0x%08X\r\n", LPC_SC->CCLKCFG);
00031     
00032     int M = (LPC_SC->PLL0CFG & 0xFFFF) + 1;
00033     int N = (LPC_SC->PLL0CFG >> 16) + 1;
00034     int CCLKDIV = LPC_SC->CCLKCFG + 1;
00035 
00036     pc.printf("Clock Variables:\r\n");
00037     pc.printf(" - Fin = %d\r\n", Fin);
00038     pc.printf(" - M   = %d\r\n", M);
00039     pc.printf(" - N   = %d\r\n", N);
00040     pc.printf(" - CCLKDIV = %d\r\n", CCLKDIV);
00041 
00042     int Fcco = (2 * M * 12000000) / N;
00043     int CCLK = Fcco / CCLKDIV;
00044 
00045     pc.printf("Clock Results:\r\n");    
00046     pc.printf(" - Fcco = %d\r\n", Fcco);
00047     
00048     printf(" - CCLK = %d\r\n", CCLK);
00049     
00050     printf("Run CoreMark? (Y/N)\n");
00051     char buf[8];
00052     scanf("%s", buf);
00053     if (buf[0] == 'y' || buf[0] == 'Y')
00054     {
00055         mainCoreMark();
00056     }
00057     
00058     wait(1);
00059     NVIC_SystemReset();
00060     }
00061 }