2020年03月09日 | s3c6410 裸机----时钟

目标：编一个 pwm 控制蜂鸣器 5秒叫，5秒shut up

了解系统时钟：

可以看到那个pwm受apb控制，而APB 的时钟是受，MPLL 控制的，这是我要关心的流程图，而每个register的

的功能都可以在datasheet中找到，研究一下就可以了，可以发现那些

那些值的设置都是顾定的，see（we recommended only the values in the PLL value recommendation table），

所以推测 有初始化的时钟，只需获取pclk，然后分频就可以得到要的时钟频率了。·······请大牛们看到了，如果你们写了设置系统时钟的code，成功了 ，给我一分，我想学习一下。

void SYSC_GetClkInform( void)

{

u8 muxApll, muxMpll, muxSync;

u8 divApll, divHclkx2, divHclk, divPclk;

u16 pllM, pllP, pllS;

u32 temp;

////

// clock division ratio

temp = Inp32(rCLK_DIV0);

divApll = temp & 0xf;

divHclkx2 = (temp>>9) & 0x7;

divHclk = (temp>>8) & 0x1;

divPclk = (temp>>12) & 0xf;

////

// Operating Mode

temp = Inp32(rOTHERS);

temp = (temp>>8)&0xf;

if(temp)

{

g_SYNCACK = 1;

}

else

{

g_SYNCACK = 0;

}

////

// ARMCLK

muxApll = Inp32(rCLK_SRC) & 0x1;

if(muxApll) //FOUT

{

temp = Inp32(rAPLL_CON);

pllM = (temp>>16)&0x3ff;

pllP = (temp>>8)&0x3f;

pllS = (temp&0x7);

g_APLL = ((FIN>>pllS)/pllP)*pllM;

}

else //FIN

{

g_APLL = FIN;

}

g_ARMCLK = g_APLL/(divApll+1);

////

// HCLK

muxSync = (Inp32(rOTHERS)>>7) & 0x1;

if(muxSync) //synchronous mode

{

g_HCLKx2 = g_APLL/(divHclkx2+1);

temp = Inp32(rMPLL_CON);

pllM = (temp>>16)&0x3ff;

pllP = (temp>>8)&0x3f;

pllS = (temp&0x7);

g_MPLL = ((FIN>>pllS)/pllP)*pllM;

}

else

{

muxMpll = (Inp32(rCLK_SRC)>>1) & 0x1;

if(muxMpll) //FOUT

{

temp = Inp32(rMPLL_CON);

pllM = (temp>>16)&0x3ff;

pllP = (temp>>8)&0x3f;

pllS = (temp&0x7);

g_MPLL = ((FIN>>pllS)/pllP)*pllM;

}

else //FIN

{

g_MPLL = FIN;

}

g_HCLKx2 = g_MPLL/(divHclkx2+1);

}

g_HCLK = g_HCLKx2/(divHclk+1);

////

// PCLK

g_PCLK = g_HCLKx2/(divPclk+1);

return;

}

研究一下，getpclk。

timer0 的控制程序：

main.c

#include "gpio.h"

#include "sfr6410.h"

#include "timer.h"

#include "sysc.h"

#include "library.h"

//设置system time

//设置 timer 

//gpio设置,pwm ,out

// set pwm tout[0]

void BuzzInit()  

{

u32 TEMP;

TEMP = GPIO->rGPIOFCON;

TEMP &= ~(0X3<<28) ;

TEMP |=(0X2<<28);

GPIO->rGPIOFCON = TEMP;

TEMP = GPIO->rGPIOFDAT ;

TEMP &= ~(0x1 <<14);

GPIO->rGPIOFDAT = TEMP;

}

//void SystemTimeInit() //研究发现，默认MPLL，控制apb时钟为400M

void TimerInit()

{

u32 TEMP;

//  1M  设置 time input clock = pclk /（prescaler）/（divier）

TEMP = Inp32(rTCFG0 );

TEMP &=~(0XFF);

TEMP |=0X42;

Outp32(rTCFG0,TEMP);

// tcntb0 tcmpb0 loadvalue,0.1S

TEMP = Inp32(rTCNTB0);

    TEMP = 0x989680;

Outp32(rTCNTB0,TEMP);

TEMP = Inp32(rTCMPB0);

TEMP = 0x4c4b40;

Outp32(rTCMPB0,TEMP);

//tcon ,MANUAL load,output,update,o THEN UPLOAD,START

TEMP = Inp32(rTCON);

TEMP &=~(0XF);

TEMP |=0X2;

Outp32(rTCON,TEMP);

TEMP &=~(0XF);

TEMP |=0X9;

Outp32(rTCON,TEMP);

}

//void IntInit();

void main()

{ 

SYSC_GetClkInform();

BuzzInit();

TimerInit();

while(1);

}

timer.h

#include "def.h"

#include "sfr6410.h"

#include "system.h"

#define FIN       12000000

enum TIMER_REG

{

rTCFG0   = PWMTIMER_BASE+0x00,

rTCFG1   = PWMTIMER_BASE+0x04,

rTCON    = PWMTIMER_BASE+0x08,

rTCNTB0  = PWMTIMER_BASE+0x0C,

rTCMPB0  = PWMTIMER_BASE+0x10,

rTCNTO0  = PWMTIMER_BASE+0x14,

rTCNTB1  = PWMTIMER_BASE+0x18,

rTCMPB1  = PWMTIMER_BASE+0x1C,

rTCNTO1  = PWMTIMER_BASE+0x20,

rTCNTB2  = PWMTIMER_BASE+0x24,

rTCMPB2  = PWMTIMER_BASE+0x28,

rTCNTO2  = PWMTIMER_BASE+0x2C,

rTCNTB3  = PWMTIMER_BASE+0x30,

rTCMPB3  = PWMTIMER_BASE+0x34,

rTCNTO3  = PWMTIMER_BASE+0x38,

rTCNTB4  = PWMTIMER_BASE+0x3C,

rTCNTO4  = PWMTIMER_BASE+0x40,

rTINT_CSTAT = PWMTIMER_BASE+0x44,

rWTCON= WDT_BASE+0x00,

rWTDAT = WDT_BASE+0x04,

rWTCNT = WDT_BASE+0x08,

rWTCLRINT = WDT_BASE+0x0C

};