?? mcp2510.c
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/************************************************************************************\
MCP2510 CAN總線試驗演示程序2003.10
\************************************************************************************/
#include "44b.h"
#include "EXIO.h"
#include "MCP2510.h"
/********************** MCP2510 Pin *********************************/
#define MCP2510_CS 0x4 //EXIO2
/********************** MCP2510 Instruction *********************************/
#define MCP2510INSTR_RESET 0xc0
#define MCP2510INSTR_READ 0x03
#define MCP2510INSTR_WRITE 0x02
#define MCP2510INSTR_RTS 0x80 //request to send
#define MCP2510INSTR_RDSTAT 0xa0 //read status
#define MCP2510INSTR_BITMDFY 0x05 //bit modify
#define MCP2510_Enable() do{CLREXIOBIT(MCP2510_CS);}while(0)
#define MCP2510_Disable() do{SETEXIOBIT(MCP2510_CS); Delay(1);}while(0)
void MCP2510_Reset()
{
MCP2510_Enable();
SendSIOData(MCP2510INSTR_RESET);
MCP2510_Disable();
}
void MCP2510_Write(int address, int value)
{
MCP2510_Enable();
SendSIOData(MCP2510INSTR_WRITE);
SendSIOData((unsigned char)address);
SendSIOData((unsigned char)value);
MCP2510_Disable();
}
unsigned char MCP2510_Read(int address)
{
unsigned char result;
MCP2510_Enable();
SendSIOData(MCP2510INSTR_READ);
SendSIOData((unsigned char)address);
SendSIOData(0);
result=ReadSIOData();
MCP2510_Disable();
return result;
}
unsigned char MCP2510_ReadStatus()
{
unsigned char result;
MCP2510_Enable();
SendSIOData(MCP2510INSTR_RDSTAT);
SendSIOData(0);
result=ReadSIOData();
MCP2510_Disable();
return result;
}
void MCP2510_WriteBits( int address, int data, int mask )
{
MCP2510_Enable();
SendSIOData(MCP2510INSTR_BITMDFY);
SendSIOData((unsigned char)address);
SendSIOData((unsigned char)mask);
SendSIOData((unsigned char)data);
MCP2510_Disable();
}
void MCP2510_SetBandRate(CanBandRate bandrate, BOOL IsBackNormal)
{
//
// Bit rate calculations.
//
//Input clock fre=16MHz
// In this case, we'll use a speed of 125 kbit/s, 250 kbit/s, 500 kbit/s.
// If we set the length of the propagation segment to 7 bit time quanta,
// and we set both the phase segments to 4 quanta each,
// one bit will be 1+7+4+4 = 16 quanta in length.
//
// setting the prescaler (BRP) to 0 => 500 kbit/s.
// setting the prescaler (BRP) to 1 => 250 kbit/s.
// setting the prescaler (BRP) to 3 => 125 kbit/s.
//
// If we set the length of the propagation segment to 3 bit time quanta,
// and we set both the phase segments to 1 quanta each,
// one bit will be 1+3+2+2 = 8 quanta in length.
// setting the prescaler (BRP) to 0 => 1 Mbit/s.
// Go into configuration mode
MCP2510_Write(MCP2510REG_CANCTRL, MODE_CONFIG);
switch(bandrate){
case BandRate_125kbps:
MCP2510_Write(CNF1, SJW1|BRP4); //Synchronization Jump Width Length =1 TQ
MCP2510_Write(CNF2, BTLMODE_CNF3|(SEG4<<3)|SEG7); // Phase Seg 1 = 4, Prop Seg = 7
MCP2510_Write(CNF3, SEG4);// Phase Seg 2 = 4
break;
case BandRate_250kbps:
MCP2510_Write(CNF1, SJW1|BRP2); //Synchronization Jump Width Length =1 TQ
MCP2510_Write(CNF2, BTLMODE_CNF3|(SEG4<<3)|SEG7); // Phase Seg 1 = 4, Prop Seg = 7
MCP2510_Write(CNF3, SEG4);// Phase Seg 2 = 4
break;
case BandRate_500kbps:
MCP2510_Write(CNF1, SJW1|BRP1); //Synchronization Jump Width Length =1 TQ
MCP2510_Write(CNF2, BTLMODE_CNF3|(SEG4<<3)|SEG7); // Phase Seg 1 = 4, Prop Seg = 7
MCP2510_Write(CNF3, SEG4);// Phase Seg 2 = 4
break;
case BandRate_1Mbps:
MCP2510_Write(CNF1, SJW1|BRP1); //Synchronization Jump Width Length =1 TQ
MCP2510_Write(CNF2, BTLMODE_CNF3|(SEG3<<3)|SEG2); // Phase Seg 1 = 2, Prop Seg = 3
MCP2510_Write(CNF3, SEG2);// Phase Seg 2 = 1
break;
}
if(IsBackNormal){
//Enable clock output
MCP2510_Write(CLKCTRL, MODE_NORMAL | CLKEN | CLK1);
}
}
/*******************************************\
* 序列讀取MCP2510數據 *
\*******************************************/
void MCP2510_SRead( int address, unsigned char* pdata, int nlength )
{
int i;
MCP2510_Enable();
SendSIOData(MCP2510INSTR_READ);
SendSIOData((unsigned char)address);
for (i=0; i<nlength; i++) {
SendSIOData(0);
*pdata=ReadSIOData();
pdata++;
}
MCP2510_Disable();
}
/*******************************************\
* 序列寫入MCP2510數據 *
\*******************************************/
void MCP2510_Swrite(int address, unsigned char* pdata, int nlength)
{
int i;
MCP2510_Enable();
SendSIOData(MCP2510INSTR_WRITE);
SendSIOData((unsigned char)address);
for (i=0; i < nlength; i++) {
SendSIOData((unsigned char)*pdata);
pdata++;
}
MCP2510_Disable();
}
/*******************************************\
* 讀取MCP2510 CAN總線ID *
* 參數: address為MCP2510寄存器地址*
* can_id為返回的ID值 *
* 返回值 *
* TRUE，表示是擴展ID(29位) *
* FALSE，表示非擴展ID(11位) *
\*******************************************/
BOOL MCP2510_Read_Can_ID( int address, U32* can_id)
{
U32 tbufdata;
unsigned char* p=(unsigned char*)&tbufdata;
MCP2510_SRead(address, p, 4);
*can_id = (tbufdata<<3)|((tbufdata>>13)&0x7);
*can_id &= 0x7ff;
if ( (p[MCP2510LREG_SIDL] & TXB_EXIDE_M) == TXB_EXIDE_M ) {
*can_id = (*can_id<<2) | (p[MCP2510LREG_SIDL] & 0x03);
*can_id <<= 16;
*can_id |= tbufdata>>16;
return TRUE;
}
return FALSE;
}
/***********************************************************\
* 讀取MCP2510 接收的數據 *
* 參數: nbuffer為第幾個緩沖區可以為3或者4 *
* can_id為返回的ID值 *
* rxRTR表示是否是RXRTR *
* data表示讀取的數據 *
* dlc表示data length code *
* 返回值 *
* TRUE，表示是擴展總線 *
* FALSE，表示非擴展總線 *
\***********************************************************/
BOOL MCP2510_Read_Can(U8 nbuffer, BOOL* rxRTR, U32* can_id, U8* data , U8* dlc)
{
U8 mcp_addr = (nbuffer<<4) + 0x31, ctrl;
BOOL IsExt;
IsExt=MCP2510_Read_Can_ID( mcp_addr, can_id);
ctrl=MCP2510_Read(mcp_addr-1);
*dlc=MCP2510_Read( mcp_addr+4);
if ((ctrl & 0x08)) {
*rxRTR = TRUE;
}
else{
*rxRTR = FALSE;
}
*dlc &= DLC_MASK;
MCP2510_SRead(mcp_addr+5, data, *dlc);
return IsExt;
}
/***********************************************************\
* 寫入MCP2510 發送的數據 *
* 參數: nbuffer為第幾個緩沖區可以為0、1、2 *
* ext表示是否是擴展總線 *
* can_id為返回的ID值 *
* rxRTR表示是否是RXRTR *
* data表示讀取的數據 *
* dlc表示data length code *
* FALSE，表示非擴展總線 *
\***********************************************************/
void MCP2510_Write_Can( U8 nbuffer, BOOL ext, U32 can_id, BOOL rxRTR, U8* data,U8 dlc )
{
U8 mcp_addr = (nbuffer<<4) + 0x31;
MCP2510_Swrite(mcp_addr+5, data, dlc ); // write data bytes
MCP2510_Write_Can_ID( mcp_addr, can_id,ext); // write CAN id
if (rxRTR)
dlc |= RTR_MASK; // if RTR set bit in byte
MCP2510_Write((mcp_addr+4), dlc); // write the RTR and DLC
}
/*******************************************\
* 設置MCP2510 CAN總線ID *
* 參數: address為MCP2510寄存器地址*
* can_id為設置的ID值 *
* IsExt表示是否為擴展ID *
\*******************************************/
void MCP2510_Write_Can_ID(int address, U32 can_id, BOOL IsExt)
{
U32 tbufdata;
if (IsExt) {
can_id&=0x1fffffff; //29位
tbufdata=can_id &0xffff;
tbufdata<<=16;
tbufdata|=(can_id>>(18-5)&(~0x1f));
tbufdata |= TXB_EXIDE_M;
}
else{
can_id&=0x7ff; //11位
tbufdata= (can_id>>3)|((can_id&0x7)<<13);
}
MCP2510_Swrite(address, (unsigned char*)&tbufdata, 4);
}
// Setup the CAN buffers used by the application.
// We currently use only one for reception and one for transmission.
// It is possible to use several to get a simple form of queue.
//
// We setup the unit to receive all CAN messages.
// As we only have at most 4 different messages to receive, we could use the
// filters to select them for us.
//
// mcp_init() should already have been called.
void canSetup(void)
{
// As no filters are active, all messages will be stored in RXB0 only if
// no roll-over is active. We want to recieve all CAN messages (standard and extended)
// (RXM<1:0> = 11).
//SPI_mcp_write_bits(RXB0CTRL, RXB_RX_ANY, 0xFF);
//SPI_mcp_write_bits(RXB1CTRL, RXB_RX_ANY, 0xFF);
// But there is a bug in the chip, so we have to activate roll-over.
MCP2510_WriteBits(RXB0CTRL, (RXB_BUKT+RXB_RX_ANY), 0xFF);
MCP2510_WriteBits(RXB1CTRL, RXB_RX_ANY, 0xFF);
}
/***********************************************************************************\
發送數據
參數:
data，發送數據
Note: 使用三個緩沖區循環發送，沒有做緩沖區有效檢測
\***********************************************************************************/
void canWrite(U32 id, U8 *pdata, unsigned char dlc, BOOL IsExt, BOOL rxRTR)
{
static int ntxbuffer=0;
MCP2510_Write_Can(ntxbuffer, IsExt, id, rxRTR, pdata, dlc);
switch(ntxbuffer){
case 0:
MCP2510_transmit(TXB0CTRL);
ntxbuffer=1;
break;
case 1:
MCP2510_transmit(TXB1CTRL);
ntxbuffer=2;
break;
case 2:
MCP2510_transmit(TXB2CTRL);
ntxbuffer=0;
break;
}
}
void init_MCP2510(CanBandRate bandrate)
{
unsigned char i,j,a;
MCP2510_Reset();
// for(i=0;i<255;i++)
// Uart_Printf("%x\n",MCP2510_Read(i));
MCP2510_SetBandRate(bandrate,FALSE);
// Disable interrups.
MCP2510_Write(CANINTE, NO_IE);
// Mark all filter bits as don't care:
MCP2510_Write_Can_ID(RXM0SIDH, 0,1);
MCP2510_Write_Can_ID(RXM1SIDH, 0,1);
// Anyway, set all filters to 0:
MCP2510_Write_Can_ID(RXF0SIDH, 0, 0);
MCP2510_Write_Can_ID(RXF1SIDH, 0, 0);
MCP2510_Write_Can_ID(RXF2SIDH, 0, 0);
MCP2510_Write_Can_ID(RXF3SIDH, 0, 0);
MCP2510_Write_Can_ID(RXF4SIDH, 0, 0);
MCP2510_Write_Can_ID(RXF5SIDH, 0, 0);
//Enable clock output
//MCP2510_Write(CLKCTRL, MODE_LOOPBACK| CLKEN | CLK1);//回環模式
MCP2510_Write(CLKCTRL, MODE_NORMAL| CLKEN | CLK1);//標準模式
//如果不能用兩臺設備聯機實驗的話，可以選擇回環模式
//這樣在超級終端中可以顯示鍵盤的輸入
// Clear, deactivate the three transmit buffers
a = TXB0CTRL;
for (i = 0; i < 3; i++) {
for (j = 0; j < 14; j++) {
MCP2510_Write(a, 0);
a++;
}
a += 2; // We did not clear CANSTAT or CANCTRL
}
// and the two receive buffers.
MCP2510_Write(RXB0CTRL, 0);
MCP2510_Write(RXB1CTRL, 0);
// The two pins RX0BF and RX1BF are used to control two LEDs; set them as outputs and set them as 00.
MCP2510_Write(BFPCTRL, 0x3C);
//Open Interrupt
MCP2510_Write(CANINTE, RX0IE|RX1IE);
}
/***********************************************************************************\
查詢是否收到數據
返回值:如果沒有數據，則返回-1，
否則，返回收到數據的緩沖區號
Note: 如果兩個緩沖區都收到數據，則返回第一個緩沖區
\***********************************************************************************/
int canPoll()
{
if(MCP2510_ReadStatus()&RX0INT)
return 0;
if(MCP2510_ReadStatus()&RX1INT)
return 1;
return -1;
}
BOOL canRead(int n, U32* id, U8 *pdata, U8*dlc, BOOL* rxRTR, BOOL *isExt)
{
U8 byte;
byte=MCP2510_Read(CANINTF);
if(n==0){
if(byte & RX0INT){
*isExt=MCP2510_Read_Can(n+3, rxRTR, id, pdata, dlc);
MCP2510_WriteBits(CANINTF, ~RX0INT, RX0INT); // Clear interrupt
}
return FALSE;
}
else if(n ==1 ){
if(byte & RX1INT){
*isExt=MCP2510_Read_Can(n+4, rxRTR, id, pdata, dlc);
MCP2510_WriteBits(CANINTF, ~RX1INT, RX1INT); // Clear interrupt
}
return FALSE;
}
}
void CAN_Test()
{
int i;
U32 id;
unsigned char dlc;
BOOL rxRTR, isExt;
BOOL temp;
U8 data[8]={1,2,3,4,5,6,7,8};
init_MCP2510(BandRate_125kbps);
canSetup();
canWrite(0x123, data, 8, FALSE, FALSE);
memset(data,0,8);
Delay(100);
while((i=canPoll())==-1);
temp=canRead(i, &id, data, &dlc, &rxRTR, &isExt);
Uart_Printf("\nid=%x",id);
Uart_Printf("\ndata=%x,%x,%x,%x",data[0],data[1],data[2],data[3]);
// temp=canRead(1, &id, data, &dlc, &rxRTR, &isExt);
}
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