/*********************************************************************
*
* CAN driver
*
*********************************************************************
* FileName: CAN.c
*
* Author Date Comment
*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
* Johan Böhlin 21-10-06 Original (Rev 1.0)
********************************************************************/
#include "../Include/CANdefs.h"
#include "../Include/stackTasks.h"
#include "../Include/CAN.h"
#include "../Include/uart.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_MESSAGE cm;
// Set extended mode or not.
cm.extended=(RXB0SIDLbits.EXID==0?FALSE:TRUE);
// Clear
cm.ident=0;
if (cm.extended==TRUE)
{
//Read extended ident.
//xx xx xx 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
//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
cm.ident = (((DWORD)RXB0SIDH)<<21) + (((DWORD)(RXB0SIDL & 0xE0))<<13) + (((DWORD)(RXB0SIDL & 0x03))<<16) + (((DWORD)RXB0EIDH)<<8) + (BYTE)RXB0EIDL;
}
else
{
//Read standard ident.
//xx xx xx xx xx 10 09 08 07 06 05 04 03 02 01 00
//RXB0SIDH 10 09 08 07 06 05 04 03
//RXB0SIDL 02 01 00 xx xx xx xx xx
cm.ident = (((DWORD)RXB0SIDH)<<3) + (((DWORD)RXB0SIDL)>>5);
}
// Data length
cm.data_length=RXB0DLC;
// 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_MESSAGE cm)
{
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 (cm.extended==TRUE)
{
//Write extended ident.
//xx xx xx 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
//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
RXB0SIDH = (BYTE)((cm.ident>>21));
RXB0SIDL = ((BYTE)(cm.ident>>16) & 0x03) + ((BYTE)(cm.ident>>13) & 0xE0);
RXB0EIDH = (BYTE)(cm.ident>>8);
RXB0EIDL = (BYTE)cm.ident;
}
else
{
//Write standard ident.
//xx xx xx xx xx 10 09 08 07 06 05 04 03 02 01 00
//RXB0SIDH 10 09 08 07 06 05 04 03
//RXB0SIDL 02 01 00 xx xx xx xx xx
RXB0SIDH= (BYTE)(cm.ident>>3);
RXB0SIDL= ((BYTE)(cm.ident<<5) & 0xE0);
}
// Data length
if (cm.data_length>8) RXB0DLC=8; else RXB0DLC=cm.data_length;
// 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=(cm.extended==TRUE?1:0);
// mark as redy to transmit
_asm
bsf RXB0CON, 3, 0
_endasm
return TRUE;
}
#endif //USE_CAN