/*********************************************************************
*
* CAN driver
*
*********************************************************************
* FileName: CAN.c
*
* Author Date Comment
*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
* Johan Böhlin 21-10-06 Original (Rev 1.0)
********************************************************************/
#include <CANdefs.h>
#include <stackTasks.h>
#include <CAN.h>
static void canGetPacket(void);
#ifdef USE_CAN
/*
* Function: canInit
*
* Input: none
* Output: none
* Pre-conditions: none
* Affects: Changes can registers.
* Depends: none.
*/
void canInit()
{
CANCON = 0x80; //request config mode
while ((CANSTAT & 0xE0) != 0x80 ); //wait for config mode request
// BAUD AND TQS
BRGCON1=0;
// Sync_Seq = 2 x TQ = 1
BRGCON1bits.SJW1=0;
BRGCON1bits.SJW0=1;
// Setting BRP.
BRGCON1=BRGCON1|CAN_BRP;
// Maximum PHEG1
BRGCON2bits.SEG2PHTS = 1;
// Phase_Seg1 = 2 x TQ = 1
BRGCON2bits.SEG1PH2 = 0;
BRGCON2bits.SEG1PH1 = 0;
BRGCON2bits.SEG1PH0 = 1;
// Prop_Seq = 2 x TQ = 1
BRGCON2bits.PRSEG2 = 0;
BRGCON2bits.PRSEG1 = 0;
BRGCON2bits.PRSEG0 = 1;
// Enableing bus wake-up
BRGCON3bits.WAKDIS = 0;
// Dont use filter when wakeup
BRGCON3bits.WAKFIL = 0;
// Phase_Seg2 = 2 x TQ = 1
BRGCON3bits.SEG2PH2 = 0;
BRGCON3bits.SEG2PH1 = 0;
BRGCON3bits.SEG2PH0 = 1;
ECANCON=0;
ECANCONbits.MDSEL1 = 0;
ECANCONbits.MDSEL0 = 1;
// FILTERS AND MASKS
RXB0CONbits.RXM1=1;
RXB0CONbits.RXM0=0;
// INTERRUPTS
// Diable transmit interrupt
TXBIE = 0;
//rx any interrupt
PIR3 = 0;
PIE3 = 0b00000011;
// High interrupt
IPR3 =0b00000011;
// Programmable buffers interrupt
BIE0 = 0xFF;
//loopback mode or not
#ifdef CAN_LOOPBACK_MODE
CANCON = 0x40;//request loopback mode
while ((CANSTAT & 0xE0) != 0x40 );//wait for loopback mode
#else
CANCON = 0x00;//request normal mode
while ((CANSTAT & 0xE0) != 0x00 );//wait for normal mode
#endif
}
/*
* Function: canISR
*
* Input: none
* Output: none
* Pre-conditions: a call to canInit()
* Affects: interrupt registers and receive data buffers
* Depends: ..
*/
void canISR()
{
if (PIR3bits.RXBnIF || PIR3bits.RXB1IF || PIR3bits.RXB0IF)
{
// Get which buffer that is ful.
if (RXB0CONbits.RXFUL) { ECANCON=(ECANCON&0b00000)|0b10000; canGetPacket(); }
else if (RXB1CONbits.RXFUL) { ECANCON=(ECANCON&0b00000)|0b10001; canGetPacket(); }
else if (B0CONbits.RXFUL) { ECANCON=(ECANCON&0b00000)|0b10010; canGetPacket(); }
else if (B1CONbits.RXFUL) { ECANCON=(ECANCON&0b00000)|0b10011; canGetPacket(); }
else if (B2CONbits.RXFUL) { ECANCON=(ECANCON&0b00000)|0b10100; canGetPacket(); }
else if (B3CONbits.RXFUL) { ECANCON=(ECANCON&0b00000)|0b10101; canGetPacket(); }
else if (B4CONbits.RXFUL) { ECANCON=(ECANCON&0b00000)|0b10110; canGetPacket(); }
else if (B5CONbits.RXFUL) { ECANCON=(ECANCON&0b00000)|0b10111; canGetPacket(); }
if (PIR3bits.RXBnIF) {PIR3bits.RXBnIF = 0;}
if (PIR3bits.RXB1IF) {PIR3bits.RXB1IF = 0;}
if (PIR3bits.RXB0IF) {PIR3bits.RXB0IF = 0;}
}
}
/*
* Function: canGetPacket
*
* Input: none
* Output: none
* Pre-conditions: a call to canISR and an packet is available and banked to RXB0
* Affects: Calls canParse() function in main for parsing received packet.
* Depends: none.
*/
void canGetPacket()
{
CAN_PROTO_MESSAGE cm;
//RXB0SIDH 28 27 26 25 24 23 22 21
//RXB0SIDL 20 19 18 xx xx xx 17 16
//RXB0EIDH 15 14 13 12 11 10 09 08
//RXB0EIDL 07 06 05 04 03 02 01 00
//funct xx xx xx xx 28 27 26 25
//funcc xx xx xx xx xx xx 24 23 22 21 20 19 18 17 16 15
//nid xx xx 14 13 12 11 10 09
//sid xx xx xx xx xx xx xx 08 07 06 05 04 03 02 01 00
cm.funct=((RXB0SIDH & 0xF0)>>4);
cm.funcc=(((WORD)(RXB0SIDH & 0x0F))<<6)+(((WORD)(RXB0SIDL & 0xE0))>>2)+(((WORD)(RXB0SIDL & 0x03))<<1)+(((WORD)(RXB0EIDH & 0x80))>>7);
cm.nid=((RXB0EIDH & 0x7E)>>1);
cm.sid=(((WORD)(RXB0EIDH & 0x01))<<8)+RXB0EIDL;
// Data length
cm.data_length=(RXB0DLCbits.DLC3<<3)+(RXB0DLCbits.DLC2<<2)+(RXB0DLCbits.DLC1<<1)+RXB0DLCbits.DLC0;
// Remote request
cm.remote_request=(RXB0DLCbits.RXRTR==0?FALSE:TRUE);
// Data one bye one, for speed
cm.data[0]=RXB0D0; cm.data[1]=RXB0D1;
cm.data[2]=RXB0D2; cm.data[3]=RXB0D3;
cm.data[4]=RXB0D4; cm.data[5]=RXB0D5;
cm.data[6]=RXB0D6; cm.data[7]=RXB0D7;
// Clear ful status
RXB0CONbits.RXFUL=0;
//Call main parser
canParse(cm);
}
/*
* Function: canSendMessage
*
* Input: CAN_MESSAGE to send
* Output: True if packet scheduled sucess, false otherwise.
* Pre-conditions: canInit
* Affects: ..
* Depends: ..
*/
BOOL canSendMessage(CAN_PROTO_MESSAGE cm,CAN_PRIORITY prio)
{
if ( TXB0CONbits.TXREQ == 0 ) { ECANCON=(ECANCON&0b00000)|0b00011; }
if ( TXB1CONbits.TXREQ == 0 ) { ECANCON=(ECANCON&0b00000)|0b00100; }
if ( TXB2CONbits.TXREQ == 0 ) { ECANCON=(ECANCON&0b00000)|0b00101; }
// None of the transmit buffers were empty.
else { return FALSE;}
if (prio<0 || prio>3) prio = 0;
//RXB0SIDH 28 27 26 25 24 23 22 21
//RXB0SIDL 20 19 18 xx xx xx 17 16
//RXB0EIDH 15 14 13 12 11 10 09 08
//RXB0EIDL 07 06 05 04 03 02 01 00
//funct xx xx xx xx 28 27 26 25
//funcc xx xx xx xx xx xx 24 23 22 21 20 19 18 17 16 15
//nid xx xx 14 13 12 11 10 09
//sid xx xx xx xx xx xx xx 08 07 06 05 04 03 02 01 00
RXB0SIDH = (BYTE)((cm.funct & 0x0F)<<4)+(BYTE)((cm.funcc & 0x03C0)>>6);
RXB0SIDL = (BYTE)((cm.funcc & 0x003F)<<2)+(BYTE)((cm.funcc & 0x0006)>>1);
RXB0EIDH = (BYTE)((cm.funcc & 0x0001)<<7)+(BYTE)((cm.nid & 0x3F)<<1)+(BYTE)((cm.sid & 0x0100)>>8);
RXB0EIDL = (BYTE)((cm.sid & 0x00FF));
// Data length
RXB0DLC = 0;
if (cm.data_length>8) RXB0DLC=8; else RXB0DLC=cm.data_length;
// Remote request
if (cm.remote_request==TRUE)
{
_asm
bsf RXB0DLC, 6, 0
_endasm
}
else
{
_asm
bcf RXB0DLC, 6, 0
_endasm
}
// Data one bye one, for speed
RXB0D0=cm.data[0]; RXB0D1=cm.data[1];
RXB0D2=cm.data[2]; RXB0D3=cm.data[3];
RXB0D4=cm.data[4]; RXB0D5=cm.data[5];
RXB0D6=cm.data[6]; RXB0D7=cm.data[7];
// set extended or not
RXB0SIDLbits.EXID=1;
// Priority
RXB0CON = (RXB0CON & 0b11111100) | prio;
// mark as redy to transmit
_asm
bsf RXB0CON, 3, 0
_endasm
return TRUE;
}
#endif //USE_CAN