PIC24HJ64GP502 ECAN will nicht

[Michael Stahl (Gast)]

Hallo,

ich versuche gerade das ECAN Modul eines PIC24HJ64GP502 zum laufen zu 
bekommen, allerdings klappt das nicht.
Der PIC läuft mit einem externen 8 MHz Quarz und dank PLL mit 80 MHz. 
Der PIC läuft ( Pin toggeln funktioniert ).
Folgender Code soll das ECAN Modul initialisieren und die Funktion 
send_can() ist in einer while Schleife und soll dauernd was senden.
Wenn ich nun den Ausgangspin mit dem Oszi beobachte, passiert nichts.

Den gleichen Code ( ohne Peripherie-Multiplexing ) habe ich auch auf 
einem dspic33fj128mc506 und dort funktionier er ( an dem Ausgangspin 
kann ich mit dem Oszi die Nachricht erkennen ).

#include "can.h"

/* Assign 32x8 Word Message Buffers for ECAN1 in DMA RAM */
unsigned int ecan1MsgBuf[32][8] __attribute__((space(dma)));

void init_can()
{
/* Set the Operating Frequency of the device to be 40MHz */
#define FCY 40000000

  //Peripherie den Pins zuweisen
  // Unlock Registers
  __builtin_write_OSCCONL(OSCCON & ~(1<<6));
  // Assign C1Rx To Pin RP12
  RPINR26bits.C1RXR = 12;
  // Assign C1Tx To Pin RP13
  RPOR6bits.RP13R = 0b10000;
  // Lock Registers
  __builtin_write_OSCCONL(OSCCON | (1<<6));

  TRISBbits.TRISB12 = 1;      //C1RX als Eingang definieren
  TRISBbits.TRISB13 = 0;      //C1TX als Ausgang definieren

/* Enable Window to Access Acceptance Filter Registers */
C1CTRL1bits.WIN=0x1;
/* Select Acceptance Filter Mask 0 for Acceptance Filter 0 */
C1FMSKSEL1bits.F0MSK=0x0;
/* Configure Acceptance Filter Mask 0 register to mask SID<2:0>
Mask Bits (11-bits) : 0b000 0000 0000 */
C1RXM0SIDbits.SID = 0x0000;
/* Configure Acceptance Filter 0 to match standard identifier
Filter Bits (11-bits): 0b011 1010 xxx */
C1RXF0SIDbits.SID = 0x01D0;
/* Acceptance Filter 0 to check for Standard Identifier */
C1RXM0SIDbits.MIDE = 0x1;
C1RXF0SIDbits.EXIDE= 0x0;
/* Acceptance Filter 0 to use Message Buffer 10 to store message */
C1BUFPNT1bits.F0BP = 0xA;
/* Filter 0 enabled for Identifier match with incoming message */
C1FEN1bits.FLTEN0=0x1;
/* Clear Window Bit to Access ECAN Control Registers */
C1CTRL1bits.WIN=0x0;

/* Set the ECAN module for Configuration Mode before writing into the Baud Rate Control Registers*/
C1CTRL1bits.REQOP = 4;
/* Wait for the ECAN module to enter into Configuration Mode */
while(C1CTRL1bits.OPMODE != 4);
/* Phase Segment 1 time is 8 TQ */
C1CFG2bits.SEG1PH = 0x7;
/* Phase Segment 2 time is set to be programmable */
C1CFG2bits.SEG2PHTS = 0x1;
/* Phase Segment 2 time is 6 TQ */
C1CFG2bits.SEG2PH = 0x5;
/* Propagation Segment time is 5 TQ */
C1CFG2bits.PRSEG = 0x4;
/* Bus line is sampled three times at the sample point */
C1CFG2bits.SAM = 0x1;
/* Synchronization Jump Width set to 4 TQ */
C1CFG1bits.SJW = 0x3;
/* Baud Rate Prescaler bits set to 1:1, i.e., TQ = (2*1*1)/ FCAN */
C1CFG1bits.BRP = 0x0;

/* Configure Message Buffer 0 for Transmission and assign priority*/
C1TR01CONbits.TXEN0 = 0x1;
C1TR01CONbits.TX0PRI = 0x3;

/*DMA0-Config-Transmit*/

/* Data Transfer Size: Word Transfer Mode */
DMA0CONbits.SIZE = 0x0;
/* Data Transfer Direction: DMA RAM to Peripheral */
DMA0CONbits.DIR = 0x1;
/* DMA Addressing Mode: Peripheral Indirect Addressing mode */
DMA0CONbits.AMODE = 0x2;
/* Operating Mode: Continuous, Ping-Pong modes disabled */
DMA0CONbits.MODE = 0x0;
/* Assign ECAN1 Transmit event for DMA Channel 0 */
DMA0REQ = 70;
/* Set Number of DMA Transfer per ECAN message to 8 words */
DMA0CNT = 7;
/* Peripheral Address: ECAN1 Transmit Register */
DMA0PAD = (volatile unsigned int)&C1TXD;
/* Start Address Offset for ECAN1 Message Buffer 0x0000 */
DMA0STA = __builtin_dmaoffset(ecan1MsgBuf);
/* Channel Enable: Enable DMA Channel 0 */
DMA0CONbits.CHEN = 0x1;
/* Channel Interrupt Enable: Enable DMA Channel 0 Interrupt */
IEC0bits.DMA0IE = 1;

/*DMA1-Config-Receive*/

/* Data Transfer Size: Word Transfer Mode */
DMA1CONbits.SIZE = 0x0;
/* Data Transfer Direction: Peripheral to DMA RAM */
DMA1CONbits.DIR = 0x0;
/* DMA Addressing Mode: Peripheral Indirect Addressing mode */
DMA1CONbits.AMODE = 0x2;
/* Operating Mode: Continuous, Ping-Pong modes disabled */
DMA1CONbits.MODE = 0x0;
/* Assign ECAN1 Receive event for DMA Channel 0 */
DMA1REQ = 34;
/* Set Number of DMA Transfer per ECAN message to 8 words */
DMA1CNT = 7;
/* Peripheral Address: ECAN1 Receive Register */
DMA1PAD = (volatile unsigned int)&C1RXD;
/* Start Address Offset for ECAN1 Message Buffer 0x0000 */
DMA1STA = 0x0000;
/* Channel Enable: Enable DMA Channel 1 */
DMA1CONbits.CHEN = 0x1;
/* Channel Interrupt Enable: Enable DMA Channel 1 Interrupt */
IEC0bits.DMA1IE = 1;

/* Put the ECAN Module into Normal Mode Operating Mode*/
C1CTRL1bits.REQOP = 0;
/* Wait for the ECAN module to enter into Normal Operating Mode */
while(C1CTRL1bits.OPMODE != 0);
}

void __attribute__((__interrupt__,no_auto_psv)) _DMA1Interrupt(void)
{
IFS0bits.DMA1IF = 0; //Clear the DMA3 Interrupt Flag
}

void send_can()
{
/* WRITE TO MESSAGE BUFFER 0 */
ecan1MsgBuf[0][0] = 0x123C;
ecan1MsgBuf[0][1] = 0x0000;
ecan1MsgBuf[0][2] = 0x8;
/* WRITE MESSAGE DATA BYTES */
ecan1MsgBuf[0][3] = 0xabcd;
ecan1MsgBuf[0][4] = 0xabcd;
ecan1MsgBuf[0][5] = 0xabcd;
ecan1MsgBuf[0][6] = 0xabcd;
/* REQUEST MESSAGE BUFFER 0 TRANSMISSION */
C1TR01CONbits.TXREQ0 = 0x1;
}

ich sitze schon seit Tagen an dem Problem, kann aber keine Lösung 
finden.

Mfg