main.c

Freescale飞思卡尔最新S12X系列16位单片机的一个例子程序

//Demonstration of simple buffered SCI

#include <hidef.h>      /* common defines and macros */
#include <mc9s12xdt512.h>     /* derivative information */
#include "xgate.h"
#pragma LINK_INFO DERIVATIVE "mc9s12xdt512"


#include <string.h>
#include "xgate.h"

extern tBuffer Buffer0;
interrupt void SCI_ISR();

/************************* Macros ******************************************/

#define ROUTE_INTERRUPT(vec_adr, cfdata)                \
  INT_CFADDR= (vec_adr) & 0xF0;                         \
  INT_CFDATA_ARR[((vec_adr) & 0x0F) >> 1]= (cfdata)

#define SCI0_VEC  0xD6 /* vector address= $xxD6 */


//Initialise the XGATE
static void SetupXGATE(void)
{
  /* initialize the XGATE vector block and
     set the XGVBR register to its start address */
  XGVBR= (unsigned int)(void*__far)(XGATE_VectorTable - XGATE_VECTOR_OFFSET);

  /* switch SCI0 interrupt to XGATE */
  ROUTE_INTERRUPT(SCI0_VEC, 0x81); /* RQST=1 and PRIO=1 */

  /* enable XGATE mode and interrupts */
  XGMCTL= 0xFBC1; /* XGE | XGFRZ | XGIE */
}


void main(void)
{
  /* put your own code here */
  EnableInterrupts;
  SetupXGATE();
  
  //Initial first SCI Buffer
  Buffer0.size = 4;
  Buffer0.character[0]='1';
  Buffer0.character[1]='2';
  Buffer0.character[2]='3';
  Buffer0.character[3]=' ';
  
  //Configure baudrate = 19200 at 25MHz
  SCI0BD = 53;
  //Enable transmitter
  SCI0CR2_TE = 1;

  /* Enable the SCI Tx interrupt to start the transfer */
  SCI0CR2_SCTIE = 1;

  for(;;) {} /* wait forever */
  /* please make sure that you never leave this function */
}

#pragma CODE_SEG __NEAR_SEG NON_BANKED 

//CPU Interrupt generated by XGATE when SIMPLE is not defined - see xgate.cxgate file
interrupt void SCI_Handler()
{
  unsigned char temp;
  //Clear XGATE interrupt flag - SCI0 is channel $6B
  XGIF1 = 0x0800;

  //Initialise buffer with new values
  Buffer0.size = 4;
  temp = Buffer0.character[0];
  Buffer0.character[0] = Buffer0.character[1];
  Buffer0.character[1] = Buffer0.character[2];
  Buffer0.character[2] = temp;
  
  /* Enable the SCI Tx interrupt to start the transfer */
  SCI0CR2_SCTIE = 1;
}