2440 driver MMA7455L source program

The microcontroller source program is as follows:

/****************************************************************

File name: Main.c

Function description: Main program

********************************************************************/

#define GLOBAL_CLK 1

#include

#include

#include "def.h"

#include "option.h"

#include "2440addr.h"

#include "2440lib.h"

#include "2440slib.h"

#include "Uart.h"

void SPI_Init(void);

void WriteByte_MMA7455L(U8 addr,U8 dat);

U8 ReadByte_MMA7455L(U8 addr);                                               

static U32 cpu_freq;       

static U32 UPLL;               

static void cal_cpu_bus_clk(void)

{

        U32 val;

        U8 m, p, s;       

        val = rMPLLCON; //MPLLCON power-on initial value is 0x00096030

        m = (val>>12)&0xff; //The result is 0x96=150

        p = (val>>4)&0x3f; //The result is 0x03=3

        s = val&3; //The result is 0

        //(m+8)*FIN*2 Do not exceed 32 digits!

        FCLK = ((m+8)*(FIN/100)*2)/((p+2)*(1<        val = rCLKDIVN;

        m = (val>>1)&3;

        p = val&1;       

        val = rCAMDIVN;

        s = val>>8;       

        switch (m) {

        case 0:

                HCLK = FCLK;

                break;

        case 1:

                HCLK = FCLK>>1;

                break;

        case 2:

                if(s&2)

                        HCLK = FCLK>>3;

                else

                        HCLK = FCLK>>2;

                break;

        case 3:

                if(s&1)

                        HCLK = FCLK/6;

                else

                        HCLK = FCLK/3;

                break;

        }       

        if(p)

                PCLK = HCLK>>1;

        else

                PCLK = HCLK;       

        if(s&0x10)

                cpu_freq = HCLK;

        else

                cpu_freq = FCLK;               

        val = rUPLLCON;

        m = (val>>12)&0xff;

        p = (val>>4)&0x3f;

        s = val&3;

        UPLL = ((m+8)*FIN)/((p+2)*(1<        UCLK = (rCLKDIVN&8)?(UPLL>>1):UPLL;

}

void Main(void)

{

        U8 key,sta;                       

        int i;                               

        U32 mpll_val = 0;

        i = 2 ;       

        switch ( i ) {

        case 0: //200

                key = 12;

                mpll_val = (92<<12)|(4<<4)|(1);

                break;

        case 1: //300

                key = 13;

                mpll_val = (67<<12)|(1<<4)|(1);

                break;

        case 2: //400M

                key = 14;

                mpll_val = (92<<12)|(1<<4)|(1);

                break;

        case 3: //440!!!

                key = 14;

                mpll_val = (102<<12)|(1<<4)|(1);

                break;

        default:

                key = 14;

                mpll_val = (92<<12)|(1<<4)|(1);

                break;

        }

        //rMPLLCON is assigned 0x5c011

        ChangeMPllValue((mpll_val>>12)&0xff, (mpll_val>>4)&0x3f, mpll_val&3);

        ChangeClockDivider(key, 12); //key=14

        cal_cpu_bus_clk();

        Port_Init(); //IO port initialization

        SPI_Init(); //SPI initialization

        MMA7455L_INIT(); //MMA7455L initialization

        Uart_Init(); //Serial port initialization

        Uart_Select(0);

        Delay(5); //Delay 10ms to let IIC and SPI get ready

        Uart_Printf("CLKCON=%x!",rCLKCON);

        Uart_Printf("Start sending data!nn");       

        //Write configuration data 0x05 to the 0x16 register of MMA7455L

        WriteByte_MMA7455L(0x16,0x05);

        //Read back the configuration value of register 0x16 to determine whether the SPI communication is successful.

        sta = ReadByte_MMA7455L (0x16);   

        Uart_Printf("sta=0x%x",sta);

        while(1)

        {

        }

}

void WriteByte_MMA7455L(U8 addr,U8 dat)

{

        int n;

        //Set chip select CS to low to enable MMA7455 in SPI mode

        rGPFDAT &= 0xef;   

        Delay(1);

        Uart_Printf("The data of SPI status register is 0x%x!n",rSPSTA0);

        while(!(rSPSTA0&0x01==0x01)) ;

        //High position 1 write operation

        rSPTDAT0 = 0x80|((addr & 0x3f)<<1);  

        Uart_Printf("The data of SPI status register is 0x%x!n",rSPSTA0);

        Uart_Printf("Write operation address sent successfully!n");       

        for(n=0;n<20;n++);       

        Uart_Printf("The data of SPI status register is 0x%x!n",rSPSTA0);

        while(!(rSPSTA0&0x01==0x01)) ;

        rSPTDAT0 = dat; //write data

        Uart_Printf("The data of SPI status register is 0x%x!n",rSPSTA0);

        Uart_Printf("Write operation data sent successfully!n");       

        for(n=0;n<20;n++);       

        // Set chip select CS to high level to end SPI communication

        rGPFDAT |= 0xff;  

        Delay(1);

}

U8 ReadByte_MMA7455L(U8 addr)

{

        int n;

        U8 Re_Dat;

        //Set chip select CS to low level to enable MMA7455L in SPI mode

        rGPFDAT &= 0xef;   

        Delay(1);       

        Uart_Printf("The data of SPI status register is 0x%x!n",rSPSTA0);

        while(!(rSPSTA0&0x01==0x01)) ;

        //Read operation high clear 0

        rSPTDAT0 = (addr & 0x3f)<<1;   

        Uart_Printf("The data of SPI status register is 0x%x!n",rSPSTA0);

        Uart_Printf("Read operation address sent successfully!n");       

        for(n=0;n<20;n++);       

        Uart_Printf("The data of SPI status register is 0x%x!n",rSPSTA0);

        while(!(rSPSTA0&0x01==0x01));

        Re_Dat = rSPRDAT0;

        Uart_Printf("The data of SPI status register is 0x%x!n",rSPSTA0);       

        for(n=0;n<20;n++);

        // Set chip select CS to high level to end SPI communication

        rGPFDAT |= 0xff;

        Delay(1);

         //Return read data

        return Re_Dat;

}

//MMA7455L initialization

void MMA7455L_INIT(void )

{

   MMA_QUEUE.MMA_HEAD=0;

   MMA_QUEUE.MMA_CUR=0;  

   SPI_WriteREG(0x16,0x05); //Level mode

   delay_nus(10);

   SPI_WriteREG(0x18,0x20);

   delay_nus(10);

   SPI_WriteREG(0x19,0x00);

   delay_nus(10);

   SPI_WriteREG(0x1a,0x00);

   delay_nus(10);

  }

//SPI initialization

void SPI_Init(void)

{       

        //Activate the SPI bit of the clock controller

        rCLKCON |= 1 << 18;

        rSPCON0 = (0<<6)|(0<<5)|(1<<4)|(1<<3)|(0<<2)|(0<<1)|1;

        //Query mode; SCK enable; host mode; clock low level is valid; format A; normal mode;

        //The SPI transmission baud rate of MMA7455 can reach up to 4MHz when the operating voltage is less than 2.4V, and up to 8MHz when it is greater than 2.4V

        //SPI baud rate is 50MHz/2/(24+1)=1MHz

        rSPPRE0 = 24;         

}