TMS32 F28335 CAN采样点设置问题
我在使用F28835 ECAN时想改下采样点，但是按照手册上的方法改，无论怎么改采样点一直为60%左右，测试方法是用CAN stress 注入干扰，哪位大神能帮我指点一下到底是程序问题还是测试方法问题？程序如下，时钟为120M，波特率 500k
oid InitECana(void) // Initialise eCAN-A module
{
/* Create a shadow register structure for the CAN control registers. This is
needed, since only 32-bit access is allowed to these registers. 16-bit access
to these registers could potentially corrupt the register contents or return
false data. This is especially true while writing to/reading from a bit
(or group of bits) among bits 16 - 31 */
struct ECAN_REGS ECanaShadow;
EALLOW; // EALLOW enables access to protected bits
/* Configure eCAN RX and TX pins for CAN operation using eCAN regs*/
ECanaShadow.CANTIOC.all = ECanaRegs.CANTIOC.all;
ECanaShadow.CANTIOC.bit.TXFUNC = 1; // The CANTX pin is used for the CAN transmit functions
ECanaRegs.CANTIOC.all = ECanaShadow.CANTIOC.all;
ECanaShadow.CANRIOC.all = ECanaRegs.CANRIOC.all;
ECanaShadow.CANRIOC.bit.RXFUNC = 1; //The CANRX pin is used for the CAN receive functions
ECanaRegs.CANRIOC.all = ECanaShadow.CANRIOC.all;
/* Configure eCAN for HECC mode - (reqd to access mailboxes 16 thru 31) */
// HECC mode also enables time-stamping feature
ECanaShadow.CANMC.all = ECanaRegs.CANMC.all;
ECanaShadow.CANMC.bit.SCB = 1; //select eCAN mode
ECanaRegs.CANMC.all = ECanaShadow.CANMC.all;
// turn on Auto Bus On to automatically get out of BUS OFF condition when things clear
ECanaShadow.CANMC.all = ECanaRegs.CANMC.all;
ECanaShadow.CANMC.bit.ABO = 0;
ECanaRegs.CANMC.all = ECanaShadow.CANMC.all;
/* Initialize all bits of 'Master Control Field' to zero */
// Some bits of MSGCTRL register come up in an unknown state. For proper operation,
// all bits (including reserved bits) of MSGCTRL must be initialized to zero
ECanaMboxes.MBOX0.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX1.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX2.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX3.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX4.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX5.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX6.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX7.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX8.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX9.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX10.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX11.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX12.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX13.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX14.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX15.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX16.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX17.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX18.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX19.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX20.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX21.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX22.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX23.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX24.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX25.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX26.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX27.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX28.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX29.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX30.MSGCTRL.all = 0x00000000;
ECanaMboxes.MBOX31.MSGCTRL.all = 0x00000000;
// TAn, RMPn, GIFn bits are all zero upon reset and are cleared again
// as a matter of precaution.
ECanaRegs.CANTA.all = 0xFFFFFFFF; /* Clear all TAn bits */
ECanaRegs.CANRMP.all = 0xFFFFFFFF; /* Clear all RMPn bits */
ECanaRegs.CANGIF0.all = 0xFFFFFFFF; /* Clear all interrupt flag bits */
ECanaRegs.CANGIF1.all = 0xFFFFFFFF;
/* Configure bit timing parameters for eCANA*/ //Initialization sequence
ECanaShadow.CANMC.all = ECanaRegs.CANMC.all;
ECanaShadow.CANMC.bit.CCR = 1 ; // Set CCR = 1 (Configuration mode requested)
ECanaRegs.CANMC.all = ECanaShadow.CANMC.all;
ECanaShadow.CANES.all = ECanaRegs.CANES.all;
// Wait for configuration mode
do
{
ECanaShadow.CANES.all = ECanaRegs.CANES.all;
} while(ECanaShadow.CANES.bit.CCE != 1 ); // Wait for CCE bit to be set..
//now configuration mode active (CCR=1, CCE=1)
ECanaShadow.CANBTC.all = 0;
/* The following block for all 150 MHz SYSCLKOUT (75 MHz CAN clock) - default. Bit rate = 1 Mbps
See Note at End of File */
// BT = (TSEG1REG+1) + (TSEG2REG+1) + 1 = Total number of Tq per bit.
// Bit rate = SYSCLKOUT / ((BRPREG+1) * BT)
// ECanaShadow.CANBTC.bit.BRPREG = 19; // 250kpbs 150 MHz SYSCLKOUT
/* if(HCU_COM_BRD == BRD_250kpa)
{
ECanaShadow.CANBTC.bit.BRPREG = 15;
ECanaShadow.CANBTC.bit.TSEG2REG = 2;//3
}
else if(HCU_COM_BRD == BRD_125kpa)
{
ECanaShadow.CANBTC.bit.BRPREG = 23;
ECanaShadow.CANBTC.bit.TSEG2REG = 7;//3
}
else*/
{
ECanaShadow.CANBTC.bit.BRPREG = 7;
ECanaShadow.CANBTC.bit.TSEG2REG = 2;//3
}
ECanaShadow.CANBTC.bit.TSEG1REG = 10;
ECanaShadow.CANBTC.bit.SJWREG = 3; //Sync Jump width = 4 Tq
ECanaShadow.CANBTC.bit.SAM = 1;
ECanaRegs.CANBTC.all = ECanaShadow.CANBTC.all;
//Nomral mode requested
ECanaShadow.CANMC.all = ECanaRegs.CANMC.all;
ECanaShadow.CANMC.bit.CCR = 0 ; // Set CCR = 0
ECanaRegs.CANMC.all = ECanaShadow.CANMC.all;
ECanaShadow.CANES.all = ECanaRegs.CANES.all;
//Wait for normal mode
do
{
ECanaShadow.CANES.all = ECanaRegs.CANES.all;
} while(ECanaShadow.CANES.bit.CCE != 0 ); // Wait for CCE bit to becleared..
//Initialization complete (now Normal mode)
/* Disable all Mailboxes*/
ECanaRegs.CANME.all = 0; // Required before writing the MSGIDs
EDIS;
ECANA_Configure_Interrupts();
}
CAN stress 设置为 用这个公式算下看：（(TSEG1REG+1)+1） /（(TSEG1REG+1) +(TSEG2REG+1) +1）
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