bsp.c

DSPic33FJ64GP206单片机的应用

/*
*********************************************************************************************************
*                                             Microchip dsPIC33FJ
*                                            Board Support Package
*
*                                                   Micrium
*                                    (c) Copyright 2005, Micrium, Weston, FL
*                                              All Rights Reserved
*
*
* File : BSP.C
* By   : Eric Shufro
*********************************************************************************************************
*/

#include "includes.h"

/*
*********************************************************************************************************
*                                         MPLAB CONFIGURATION MACROS
*********************************************************************************************************
*/

                                                     /* Disable the watchdog timer                               */
_FOSCSEL(FNOSC_PRI);
_FOSC(FCKSM_CSDCMD & OSCIOFNC_OFF & POSCMD_XT);
_FWDT(FWDTEN_OFF);
/*
*********************************************************************************************************
*                                              VARIABLES
*********************************************************************************************************
*/


/*
*********************************************************************************************************
*                                              PROTOTYPES
*********************************************************************************************************
*/

static  void  BSP_PLL_Init(void);
static  void  Tmr_TickInit(void);

/*
*********************************************************************************************************
*                                         BSP INITIALIZATION
*
* Description : This function should be called by your application code before you make use of any of the
*               functions found in this module.
*
* Arguments   : none
*********************************************************************************************************
*/

void  BSP_Init (void)
{

    BSP_PLL_Init();                                                     /* Initialize the PLL                                       */
    LED_Init();                                                         /* Initialize the I/Os for the LED controls                 */
    Tmr_TickInit();  
	Init_ADC();                                                       /* Initialize the uC/OS-II tick interrupt                   */
}

/*
*********************************************************************************************************
*                                      BSP_PLL_Init()
*
* Description : This function configures and enables the PLL with the external oscillator
*               selected as the input clock to the PLL.
*
* Notes       : 1) The PLL output frequency is calculated by FIN * (M / (N1 * N2)).
*               2) FIN is the PLL input clock frequency, defined in bsp.h as
*                  CPU_PRIMARY_OSC_FR. This is the same as the external primary 
*                  oscillator on the Explorer 16 Evaluation Board. 
*               3) M is the desired PLL multiplier
*               4) N1 is the divider for FIN before FIN enters the PLL block (Pre-Divider)
*               5) N2 is the PLL output divider (Post-Divider)
*
* Summary     :    The PLL is configured as (8MHZ) * (40 / (2 * 2)) = 80MHZ
*                  The processor clock is (1/2) of the PLL output. 
*                  Performance = 40 MIPS.                
*********************************************************************************************************
*/

void  BSP_PLL_Init (void)
{
    PLLFBD   =     38;                                                  /* Set the Multiplier (M) to 40 (2 added automatically) 	*/
    CLKDIV   =      0;                                                  /* Clear the PLL Pre Divider bits, N1 = N2 = 2              */
}

/*
*********************************************************************************************************
*                                      BSP_CPU_ClkFrq()

* Description : This function determines the CPU clock frequency (Fcy)
* Returns     : The CPU frequency in (HZ)
*********************************************************************************************************
*/

INT32U  BSP_CPU_ClkFrq (void)
{
    INT8U   Clk_Selected;
    INT8U   PLL_n1;
    INT8U   PLL_n2;
    INT16U  PLL_m;
    INT16U  FRC_Div;
    INT32U  CPU_Clk_Frq;


    PLL_m         =  (PLLFBD & PLLDIV_MASK) + 2;                        /* Get the Multiplier value                                 */
    PLL_n1        =  (CLKDIV & PLLPRE_MASK) + 2;                        /* Computer the Pre Divider value                           */
    PLL_n2        = ((CLKDIV & PLLPOST_MASK) >> 6);                     /* Get the Post Divider register value                      */
    PLL_n2        = ((PLL_n2 * 2) + 2);                                 /* Compute the Post Divider value                           */

    FRC_Div       = ((CLKDIV & FRCDIV_MASK) >> 8);                      /* Get the FRC Oscillator Divider register value            */
    FRC_Div       = ((1 << FRC_Div) * 2);                               /* Compute the FRC Divider value                            */

    Clk_Selected  =  (OSCCON & COSC_MASK) >> 12;                        /* Determine which clock source is currently selected       */
    
    switch (Clk_Selected) {
        case 0:                                                         /* Fast Oscillator (FRC) Selected                           */
        case 7:
             CPU_Clk_Frq   =   CPU_FRC_OSC_FRQ;                         /* Return the frequency of the internal fast oscillator     */
             break;

        case 1:                                                         /* Fast Oscillator (FRC) with PLL Selected                  */
             CPU_Clk_Frq   = ((CPU_FRC_OSC_FRQ  * PLL_m) /              /* Compute the PLL output frequency using the FRC as FIN    */
                              (FRC_Div * PLL_n1 * PLL_n2));
             break;

        case 2:                                                         /* Primary External Oscillator Selected                     */
             CPU_Clk_Frq   =   CPU_PRIMARY_OSC_FRQ;                     /* Return the frequency of the primary external oscillator  */
             break;

        case 3:                                                         /* Primary External Oscillator with PLL Selected            */
             CPU_Clk_Frq   = ((CPU_PRIMARY_OSC_FRQ * PLL_m) /           /* Compute the PLL output frq using the PRI EXT OSC as FIN  */
                              (PLL_n1 * PLL_n2));
             break;

        case 4:                                                         /* Secondary External Low Power Oscillator (SOSC) Selected  */
        case 5:                                                         /* Internal Low Power RC Oscillator Selected                */
             CPU_Clk_Frq   =   CPU_SECONDARY_OSC_FRQ;                   /* Return the frq of the external secondary Low Power OSC   */
             break;

        case 6:
             CPU_Clk_Frq = 0;                                           /* Return 0 for the Reserved clock setting                  */
             break;

        default:
             CPU_Clk_Frq = 0;                                           /* Return 0 if the clock source cannot be determined        */
             break;
    }

    CPU_Clk_Frq   /=  2;                                                /* Divide the final frq by 2, get the actual CPU Frq (Fcy)  */

    return (CPU_Clk_Frq);                                               /* Return the operating frequency                           */
}

/*
*********************************************************************************************************
*                                     DISABLE ALL INTERRUPTS
*
* Description : This function disables all interrupts from the interrupt controller.
*
* Arguments   : none
*********************************************************************************************************
*/

/*
*********************************************************************************************************
*                                         LED I/O INITIALIZATION
*
* Description : This function initializes the I/O Pins used by the onboard LEDs
*
* Arguments   : none
*
* Notes       : 1) Jumper JP2 on the Explorer 16 board must be connected to enable the onboard LEDs
*               2) JTAG must be DISABLED in order to utilize all of PORTA I/O Lines for LEDs
*********************************************************************************************************
*/

void  LED_Init (void)
{   
    TRISB  =  0;                                                        /* Set all PORTA pins to output                             */
    LATB   =  0xff;                                                         /* Shut off all LEDs                                        */
}

/*
*********************************************************************************************************
*                                             LED ON
*
* Description : This function is used to control any or all the LEDs on the board.
*
* Arguments   : led    is the number of the LED to control
*                      0    indicates that you want ALL the LEDs to be ON
*                      1    turns ON LED1
*                      2    turns ON LED2
*                      ...