mbxramrw.c

TMS320LF2812DSP CAN总线方案。

/*********************************************************************
* Filename: MBXRAMRW.c                                               *
*                                                                    *
* Description: This code checks the integrity and correct            *
*              functionality of the mailbox RAM in the CAN module.   *
*                                                                    *
* This test writes patterns such as 0000h, FFFFh, 5555h, AAAAh to all
* the 32 mailboxes and reads them back for verification.             *
* Any error is flagged.  
*                                            
* Last update: 12/24/2002                                            *
*********************************************************************/

#include "DSP28_Device.h"

#define COUNT  100000  // Mailbox RAM test will take place (COUNT) times..

long     i;
long	 d;
long	 loopcount = 0; // Counts the # of times the loop actually ran
long   	 errorcount = 0;

unsigned long TestMbox1 = 0;

void MBXrd(long d);  	/* This function reads from all 32 MBOXes */
void MBXwr(long d);		/* This function writes to all 32 MBOXes */  

void InitECan(void);

main() 
{

/* Initialize the CAN module */

	InitECan();	

/* Enable all Mailboxes */
	
	ECanaRegs.CANME.all = 0xFFFFFFFF;
	
/* Write to the mailbox RAM field of MBOX0 - 31 */    
     
    /* while(1) */		              // Uncomment this line for infinite iterations
    for(i=0; i < COUNT; i++)		  // Uncomment this line for finite iterations			  	
    {
     d = 0xFFFFFFFF; 
     MBXwr(d);         
     MBXrd(d);
     d = 0x00000000; 
     MBXwr(d);         
     MBXrd(d);
     d = 0x55555555; 
     MBXwr(d);         
     MBXrd(d);
     d = 0xAAAAAAAA; 
     MBXwr(d);         
     MBXrd(d);
     loopcount++;
    }   

asm(" ESTOP0");

}

// Write the passed data to all 32 mailboxes

void MBXwr(long MBXdata) 
	{
	int j;
	volatile struct MBOX *Mailbox  = (void *) 0x6100;   
		
		for(j=0; j<32; j++)								 
		{
		
		Mailbox->MDRH.all = MBXdata;
		Mailbox->MDRL.all = MBXdata;
		Mailbox = Mailbox + 1; 
		
		}			
	} 

// Check if all 32 mailboxes contain the passed data

void MBXrd(long MBXdata) 
	{	
	int j;
	volatile struct MBOX *Mailbox  = (void *) 0x6100;   
		
		for(j=0; j<32; j++)								 
		{
		
		TestMbox1 = Mailbox->MDRL.all;	
		if (TestMbox1 != d)
		 {errorcount++;}
		 
		TestMbox1 = Mailbox->MDRH.all;	
		if (TestMbox1 != d) 
		 {errorcount++;}
		 
		Mailbox = Mailbox + 1; 
		
		}	 
	} 
	
/* This code may be used to exercise and check the correct functionality
of the mailbox RAM */