main.c

mpc55**系列芯片的例程 包括SCI,SPI,TIMER,FIT,EDMA等几乎所有功能的实现

/* main.c: FlexCAN program */
/* Description: Transmit one message from FlexCAN A buf. 0 to FlexCAN C buf. 4 */
/* Rev 0.1 Jan 16, 2006 S.Mihalik, Copyright Freescale, 2006. All Rights Reserved */
/* Rev 0.2 Jun 6 2006 SM - changed Flexcan A to C & enabled 64 msg buffers */
/* Rev 0.3 Jun 15 2006 SM - 1. Made globals uninitialized */
/*         2. RecieveMsg function:  read CANx_TIMER, removed setting buffer's CODE*/
/*         3. added idle loop code for smoother Nexus trace */
/*         4. modified for newer Freescale header files (r 16) */
/* Rev 0.4 Aug 11 2006 SM - Removed redundant CAN_A.MCR init */
/* Rev 0.5 Jan 31 2007 SM - Removed other redundant CAN_C.MCR init */
/* Rev 0.6 Mar 08 2007 SM - Correced init of MBs - cleared 64 MBs, instead of 63 */
/* Rev 0.7 Jul 20 2007 SM - Changes for MPC5510 */
/* Notes:  */
/*  1. MMU not initialized; must be done by debug scripts or BAM */
/*  2. SRAM not initialized; must be done by debug scripts or in a crt0 type file */

#include "mpc563m.h" /* Use proper include file such as mpc5510.h or mpc5554.h */

uint8_t  RxCODE;               /* Received message buffer code */
uint32_t RxID;                 /* Received message ID */
uint8_t  RxLENGTH;             /* Recieved message number of data bytes */
uint8_t  RxDATA[8];            /* Received message data string*/
uint32_t RxTIMESTAMP;          /* Received message time */                         

void initCAN_A (void) {
  uint8_t   i;

  CAN_A.MCR.R = 0x5000003F;       /* Put in Freeze Mode & enable all 64 message buffers */
  CAN_A.CR.R = 0x04DB0006;        /* Configure for 8MHz OSC, 100KHz bit time */
  for (i=0; i<64; i++) {
    CAN_A.BUF[i].CS.B.CODE = 0;   /* Inactivate all message buffers */
  } 
  CAN_A.BUF[0].CS.B.CODE = 8;     /* Message Buffer 0 set to TX INACTIVE */
/* Use 1 pair of the next four lines of code for MPC551x or MPC555x */
/*SIU.PCR[48].R = 0x0620;*/       /* MPC551x: Configure pad as CNTXA, open drain */
/*SIU.PCR[49].R = 0x0500;*/       /* MPC551x: Configure pad as CNRXA */
  SIU.PCR[83].R = 0x0620;         /* MPC555x: Configure pad as CNTXA, open drain */
  SIU.PCR[84].R = 0x0500;         /* MPC555x: Configure pad as CNRXA */
  CAN_A.MCR.R = 0x0000003F;       /* Negate FlexCAN A halt state for 64 MB */
}

void initCAN_C (void) {
  uint8_t   i;

  CAN_C.MCR.R = 0x5000003F;       /* Put in Freeze Mode & enable all 64 message buffers */
  CAN_C.CR.R = 0x04DB0006;        /* Configure for 8MHz OSC, 100KHz bit time */
/* Use one of the next two lines: */
/*  for (i=0; i<64; i++) { */     /* MPC551x, MPC555x except MPC553x: init 64 buffers */
  for (i=0; i<32; i++) {          /* MPC563x: init 32 message buffers */
    CAN_C.BUF[i].CS.B.CODE = 0;   /* Inactivate all message buffers */
  } 
  CAN_C.BUF[4].CS.B.IDE = 0;      /* MB 4 will look for a standard ID */
  CAN_C.BUF[4].ID.B.STD_ID = 555; /* MB 4 will look for ID = 555 */
  CAN_C.BUF[4].CS.B.CODE = 4;     /* MB 4 set to RX EMPTY */
  CAN_C.RXGMASK.R = 0x1FFFFFFF;   /* Global acceptance mask */
/* Use 1 pair of the next four lines of code for MPC551x or MPC555x */
/*SIU.PCR[52].R = 0x0620;*/       /* MPC551x: Configure pad as CNTXC, open drain */
/*SIU.PCR[53].R = 0x0500;*/       /* MPC551x: Configure pad as CNRXC */
  SIU.PCR[87].R = 0x0E20;         /* MPC555x: Configure pad as CNTXC, open drain */
  SIU.PCR[88].R = 0x0D00;         /* MPC555x: Configure pad as CNRXC */
  CAN_C.MCR.R = 0x0000003F;       /* Negate FlexCAN C halt state for  64 MB */
}

void TransmitMsg (void) {
  uint8_t	i;
                                   /* Assumption:  Message buffer CODE is INACTIVE */
  const uint8_t TxData[] = {"Hello"};  /* Transmit string*/
  CAN_A.BUF[0].CS.B.IDE = 0;           /* Use standard ID length */
  CAN_A.BUF[0].ID.B.STD_ID = 555;      /* Transmit ID is 555 */
  CAN_A.BUF[0].CS.B.RTR = 0;           /* Data frame, not remote Tx request frame */
  CAN_A.BUF[0].CS.B.LENGTH = sizeof(TxData) -1 ; /* # bytes to transmit w/o null */
  for (i=0; i<sizeof(TxData); i++) {
    CAN_A.BUF[0].DATA.B[i] = TxData[i];      /* Data to be transmitted */
  }
  CAN_A.BUF[0].CS.B.SRR = 1;           /* Tx frame (not req'd for standard frame)*/
  CAN_A.BUF[0].CS.B.CODE =0xC;         /* Activate msg. buf. to transmit data frame */ 
}

void RecieveMsg (void) {
  uint8_t j;
  uint16_t dummy;

  while (CAN_C.IFRL.B.BUF04I == 0) {};  /* Wait for CAN C MB 4 flag */
  RxCODE   = CAN_C.BUF[4].CS.B.CODE;    /* Read CODE, ID, LENGTH, DATA, TIMESTAMP */
  RxID     = CAN_C.BUF[4].ID.B.STD_ID;
  RxLENGTH = CAN_C.BUF[4].CS.B.LENGTH;
  for (j=0; j<RxLENGTH; j++) { 
    RxDATA[j] = CAN_C.BUF[4].DATA.B[j];
  }
  RxTIMESTAMP = CAN_C.BUF[4].CS.B.TIMESTAMP; 
  dummy = CAN_C.TIMER.R;                /* Read TIMER to unlock message buffers */    
  CAN_C.IFRL.B.BUF04I = 1;              /* Clear CAN C MB 4 flag */
}

void main(void) {
  volatile uint32_t IdleCtr = 0; 

  initCAN_A();             /* Initialize FlexCAN A & one of its buffers for transmit*/
  initCAN_C();             /* Initialize FLEXCAN C & one of its buffers for receive*/
  TransmitMsg();           /* Transmit one message from a FlexCAN A buffer */
  RecieveMsg();            /* Wait for the message to be recieved at FlexCAN C */
  while (1) {              /* Idle loop: increment counter */
    IdleCtr++;               
  }
}