lin_init.c

芯科原厂所有c8051fxx程序的例子。

// Copyright (c) 2006 SILICON LABORATORIES, INC.
//
// FILE NAME   : LIN_Init.c
// TARGET MCU  : C8051F52xA-53xA
// DESCRIPTION : Initialization routines for LIN API
//
// Initializes the device.
//


//-----------------------------------------------------------------------------
// Header Files
//-----------------------------------------------------------------------------

#include <c8051F520.h>
#include "LIN.h"


//-----------------------------------------------------------------------------
// Functions
//-----------------------------------------------------------------------------

//-----------------------------------------------------------------------------
// l_sys_init ()
//-----------------------------------------------------------------------------
//
// Initializes the system hardware, including the system clock, port I/O,
//    LIN hardware and timers.
//
l_bool l_sys_init (void)
{
   // Disable Watchdog Timer
   PCA0MD = 0x00;

   Sysclk_Init ();
   Port_Init ();
   LIN_Init ();

#if (LIN_MODE == LIN_MASTER)
   Timer0_Init ();
#endif

   // Enable interrupts.
   EA = 1;

   return (1);
}

//-----------------------------------------------------------------------------
// Sysclk_Init ()
//-----------------------------------------------------------------------------
//
// Configures the system clock to frequency SYSCLK.
//
void Sysclk_Init (void)
{
   // Configure the SYSCLK for Internal Oscillator divided by the largest
   // possible divider (see LIN_Init.h for calculation of IFCN).
   OSCICN |= IFCN;
}


//-----------------------------------------------------------------------------
// Port_Init ()
//-----------------------------------------------------------------------------
//
// Configures the system clock to frequency SYSCLK.
//
void Port_Init (void)
{
   // Configure LIN TX (P0.1) as push-pull output.
   P0MDOUT = 0x02;

   // Skip P0.0.
   P0SKIP |= 0x01;

   // Enable LIN on the crossbar.
   XBR0 = 0x04;

   // Enable the crossbar.
   XBR1 = 0x40;
}

//-----------------------------------------------------------------------------
// LIN_Init ()
//-----------------------------------------------------------------------------
//
// Initializes the LIN hardware for master or slave mode.
//
void LIN_Init (void)
{

#if (LIN_MODE == LIN_MASTER)

   // Configure the device for LIN Master, manual baud rate.
   LINCF = 0xC0;

#elif (LIN_MODE == LIN_SLAVE)

#if (AUTOBAUD == TRUE)

   // Configure the device for LIN Slave, auto baud rate.
   LINCF = 0xA0;

#else

   // Configure the device for LIN Slave, manual baud rate.
   LINCF = 0x80;

#endif

#endif

}

//-----------------------------------------------------------------------------
// LIN_Bit_Rate_Init ()
//-----------------------------------------------------------------------------
//
// Initializes the bit rate of the LIN hardware.
//
void LIN_Bit_Rate_Init (void)
{
   // Load the divider, multiplier, and prescalar for LIN_BIT_RATE.

   // Load the least significant byte of the divider.
   _LIN_IREG_WRITE (LINDIV, (l_u8) LIN_DIVIDER);

   // Load the multiplier, prescalar, and most significant bit of the divider.
   _LIN_IREG_WRITE (LINMUL, (l_u8) ((LIN_PRESCALAR << 6) | (LIN_MULTIPLIER << 1) | (LIN_DIVIDER >> 8)));
}

#if (LIN_MODE == LIN_MASTER)
//-----------------------------------------------------------------------------
// Timer0_Init ()
//-----------------------------------------------------------------------------
//
// Configures Timer0 to overflow every system tick. This is the timebase used
// by the LIN master to control timing of the schedule table. LIN slave does not
// implement this function.
//
// The system tick frequency is defined as FREQUENCY_SYSTEM_TICK in LIN.h.
//
void Timer0_Init (void)
{
   // Configure Timer0 for 16-bit operation.
   TMOD |= 0x01;

   // Set Timer0 timebase.
   CKCON |= (T0M | SCA);

   // Set Timer0 to overflow immediately.
   T0 = 0xFFFF;

   // Enable Timer0 interrupts.
   ET0 = 1;

   // Start Timer0
   TR0 = 1;
}
#endif