dsPIC33EP128GP504芯片寄存器C1BUFPNT1咨询

只看该作者 · 2019-10-25 09:56

实验中发现寄存器C1BUFPNT1在接收到报文后里面的值会被修改，按照以下范例，该值为初始化设定后不被修改。求助各路大神，跪谢！

/******************************************************************************
* Function:    void Ecan1WriteRxAcptFilter(int16_t n, int32_t identifier,
*             uint16_t exide,uint16_t bufPnt,uint16_t maskSel)
*
* PreCondition:  None
*
* Input:       n-> Filter number [0-15]
*             identifier-> Bit ordering is given below
*             Filter Identifier (29-bits) :
*             0b000f ffff ffff ffff ffff ffff ffff ffff
*                   |____________|_____________________|
*                      SID10:0       EID17:0
*
*             Filter Identifier (11-bits) :
*             0b0000 0000 0000 0000 0000 0fff ffff ffff
*                                        |___________|
*                                           SID10:
*             exide -> "0" for standard identifier
*                      "1" for Extended identifier
*             bufPnt -> Message buffer to store filtered message [0-15]
*             maskSel -> Optinal Masking of identifier bits [0-3]
*
* Output:       None
*
* Side Effects:  None
*
* Overview:    Configures Acceptance filter "n" for ECAN1.
*****************************************************************************/
void Ecan1WriteRxAcptFilter( int16_t n, int32_t identifier, uint16_t exide, uint16_t bufPnt, uint16_t maskSel )
{
uint32_t sid10_0 = 0;

uint32_t eid15_0 = 0;

uint32_t eid17_16 = 0;
uint16_t *sidRegAddr;
uint16_t *bufPntRegAddr;
uint16_t *maskSelRegAddr;
uint16_t *fltEnRegAddr;

C1CTRL1bits.WIN = 1;

// Obtain the Address of CiRXFnSID, CiBUFPNTn, CiFMSKSELn and CiFEN register for a given filter number "n"
sidRegAddr = ( uint16_t * ) ( &C1RXF0SID + (n << 1) );
bufPntRegAddr = ( uint16_t * ) ( &C1BUFPNT1 + (n >> 2) );
maskSelRegAddr = ( uint16_t * ) ( &C1FMSKSEL1 + (n >> 3) );
fltEnRegAddr = ( uint16_t * ) ( &C1FEN1 );