S32K系列S32K144学习笔记——CAN驱动配置
本例程基以下如图所示接口操作，MCU为S32K144（车规级MCU），开发平台S32DSworkspace
功能描述：CAN0通信 CAN0_EN–>PB15
如有错误，麻烦帮忙指出，谢谢！
#include "S32K144.h" /* include peripheral declarations S32K144 */
#include "s32_core_cm4.h"
void WDOG_disable (void)
{
WDOG->CNT=0xD928C520; //解锁看门狗
WDOG->TOVAL=0x0000FFFF; //把时间配置为最大
WDOG->CS = 0x00002100; //关闭看门狗
}
void SOSC_init_8MHz(void)
{
SCG->SOSCDIV=0x00000101; //SOSCDIV1 & SOSCDIV2 =1: 分频/1
SCG->SOSCCFG=0x00000024; //Range=2: 选择晶体振荡器的中频范围 (SOSC 1MHz-8MHz)
// HGO=0: 控制晶体振荡器的工作功率模式 --低功率模式
// EREFS=1: 外部参考选择OSC内部晶体振荡器
while(SCG->SOSCCSR & SCG_SOSCCSR_LK_MASK); //等待SOSCCSR解锁 寄存器解锁后才可写入
SCG->SOSCCSR=0x00000001; // LK=0: SOSCCSR可以写
// SOSCCM=0: 系统OSC时钟监视器被禁用
// SOSCEN=1: 启用系统OSC
while(!(SCG->SOSCCSR & SCG_SOSCCSR_SOSCVLD_MASK)); //等待系统OSC成功启用，输出时钟有效
}
void SPLL_init_160MHz(void)
{
while(SCG->SPLLCSR & SCG_SPLLCSR_LK_MASK); //等待SPLLCSR寄存器解锁 寄存器解锁后才可写入
SCG->SPLLCSR = 0x00000000; // LK=0: SPLLCSR可以写入
// SPLLEN=0: SPLL禁用
SCG->SPLLDIV = 0x00000302; // SPLLDIV1 分频/2; SPLLDIV2 分频/4
SCG->SPLLCFG = 0x00180000; // PREDIV=0: 锁相环参考时钟分频因子
// MULT=24: SPLL时钟频率的乘法因子
// SPLL_CLK = 8MHz / 1 * 40 / 2 = 160 MHz SPLL_CLK = (VCO_CLK)/2 VCO_CLK = SPLL_SOURCE/(PREDIV+1)*(MULT+16)
while(SCG->SPLLCSR & SCG_SPLLCSR_LK_MASK); //等待SPLLCSR寄存器解锁 寄存器解锁后才可写入
SCG->SPLLCSR = 0x00000001; // LK=0: SPLLCSR可以写入
// SPLLCM=0: SPLL时钟监视器被禁用
// SPLLEN=1: 开启SPLL
while(!(SCG->SPLLCSR & SCG_SPLLCSR_SPLLVLD_MASK)); //等待SPLL成功启用，输出时钟有效
}
void NormalRUNmode_40MHz (void)
{
SCG->RCCR=SCG_RCCR_SCS(6) // SPLL做为系统时钟源
|SCG_RCCR_DIVCORE(0b11) // DIVCORE=3, 分频/4: Core clock = 160/4 MHz = 40 MHz
|SCG_RCCR_DIVBUS(0b11) // DIVBUS=3, 分频/4: bus clock = 160/4 MHz = 40 MHz
|SCG_RCCR_DIVSLOW(0b111); // DIVSLOW=7, 分频/8: SCG slow, flash clock= 160/8 MHz = 20MHZ
while (((SCG->CSR & SCG_CSR_SCS_MASK) >> SCG_CSR_SCS_SHIFT ) != 6) {}//等待系统时钟源成功选择SPLL
}
/*********************************************************************
* 函数原型：void CAN_GPIO_init (void)
* 功 能：CAN GPIO初始化
* 输入参数：无
* 返回参数：无
*
* 其他说明：
*********************************************************************/
void CAN_PORT_init (void)
{
PCC->PCCn[PCC_PORTE_INDEX] |= PCC_PCCn_CGC_MASK; //使能PTE端口时钟
PORTE->PCR[4] |= PORT_PCR_MUX(5); // Port E4: MUX = ALT5, CAN0_RX 复用
PORTE->PCR[5] |= PORT_PCR_MUX(5); // Port E5: MUX = ALT5, CAN0_TX 复用
PCC->PCCn[PCC_PORTB_INDEX] |= PCC_PCCn_CGC_MASK; //使能PTB端口时钟
PTB->PDDR |= (1<<15); //端口PTB15配置为输出
PORTB->PCR[15] = 0x00000100; //端口PTB15为GPIO
PTB->PTOR &= ~(1<<15); //输出低电平
}
/*********************************************************************
* 函数原型：void CAN0_init(void)
* 功 能：CAN0初始化
* 输入参数：无
* 返回参数：无
*
* 其他说明：
*********************************************************************/
void CAN0_init(void)
{
#define MSG_BUF_SIZE 4 /* Msg Buffer Size. (CAN 2.0AB: 2 hdr + 2 data= 4 words) */
unsigned int i=0;
PCC->PCCn[PCC_FlexCAN0_INDEX] |= PCC_PCCn_CGC_MASK; /* CGC=1: enable clock to FlexCAN0 */
CAN0->MCR |= CAN_MCR_MDIS_MASK; /* MDIS=1: Disable module before selecting clock */
CAN0->CTRL1 &= ~CAN_CTRL1_CLKSRC_MASK; /* CLKSRC=0: Clock Source = oscillator (8 MHz) */
CAN0->MCR &= ~CAN_MCR_MDIS_MASK; /* MDIS=0; Enable module config. (Sets FRZ, HALT) */
while (!((CAN0->MCR & CAN_MCR_FRZACK_MASK) >> CAN_MCR_FRZACK_SHIFT)) {} /* Good practice: wait for FRZACK=1 on freeze mode entry/exit */
CAN0->CTRL1 = 0x00DB0006; /* Configure for 500 KHz bit time */
/* Time quanta freq = 16 time quanta x 500 KHz bit time= 8MHz */
/* PRESDIV+1 = Fclksrc/Ftq = 8 MHz/8 MHz = 1 */
/* so PRESDIV = 0 */
/* PSEG2 = Phase_Seg2 - 1 = 4 - 1 = 3 */
/* PSEG1 = PSEG2 = 3 */
/* PROPSEG= Prop_Seg - 1 = 7 - 1 = 6 */
/* RJW: since Phase_Seg2 >=4, RJW+1=4 so RJW=3. */
/* SMP = 1: use 3 bits per CAN sample */
/* CLKSRC=0 (unchanged): Fcanclk= Fosc= 8 MHz */
for(i=0; i<128; i++ )
{ /* CAN0: clear 32 msg bufs x 4 words/msg buf = 128 words*/
CAN0->RAMn[i] = 0; /* Clear msg buf word */
}
for(i=0; i<16; i++ )
{ /* In FRZ mode, init CAN0 16 msg buf filters */
CAN0->RXIMR[i] = 0xFFFFFFFF; /* Check all ID bits for incoming messages */
}
CAN0->RXMGMASK = 0x1FFFFFFF; /* Global acceptance mask: check all ID bits */ //增加了周工语句后屏蔽的语句
CAN0->RAMn[ 4*MSG_BUF_SIZE + 0] = 0x04000000; /* Msg Buf 4, word 0: Enable for reception */
/* EDL,BRS,ESI=0: CANFD not used */
/* CODE=4: MB set to RX inactive */
/* IDE=0: Standard ID or Extended */
/* SRR, RTR, TIME STAMP = 0: not applicable */
#ifdef NODE_A /* Node A receives msg with std ID 0x511 */
CAN0->RAMn[ 4*MSG_BUF_SIZE + 1] = 0x14440000; /* Msg Buf 4, word 1: Standard ID = 0x111 */
#else /* Node B to receive msg with std ID 0x555 */
CAN0->RAMn[ 4*MSG_BUF_SIZE + 1] = 0x15540000; /* Msg Buf 4, word 1: Standard ID = 0x555*/
#endif
/* PRIO = 0: CANFD not used */
CAN0->MCR = 0x0000001F;//CAN_MCR_IRMQ_MASK | CAN_MCR_SRXDIS_MASK; /* Negate FlexCAN 0 halt state for 32 MBs */
CAN0->IMASK1 |= (1<<4); /* Open FIFO receives interrupt */
while ((CAN0->MCR && CAN_MCR_FRZACK_MASK) >> CAN_MCR_FRZACK_SHIFT) {}
/* Good practice: wait for FRZACK to clear (not in freeze mode) */
while ((CAN0->MCR && CAN_MCR_NOTRDY_MASK) >> CAN_MCR_NOTRDY_SHIFT) {}
/* Good practice: wait for NOTRDY to clear (module ready) */
}
/*********************************************************************
* 函数原型：void CAN0_transmit_msg(void)
* 功 能：CAN0发送数据
* 输入参数：无
* 返回参数：无
*
* 其他说明：
*********************************************************************/
void CAN0_transmit_msg(void)
{
/* Assumption: Message buffer CODE is INACTIVE */
CAN0->IFLAG1 = 0x00000001; /* Clear CAN 0 MB 0 flag without clearing others */
CAN0->RAMn[ 0*MSG_BUF_SIZE + 2] = 0xA5112233; /* MB0 word 2: data word 0 */
CAN0->RAMn[ 0*MSG_BUF_SIZE + 3] = 0x44556677; /* MB0 word 3: data word 1 */
#ifdef NODE_A
CAN0->RAMn[ 0*MSG_BUF_SIZE + 1] = 0x15540000; /* MB0 word 1: Tx msg with STD ID 0x555 */
#else
CAN0->RAMn[ 0*MSG_BUF_SIZE + 1] = 0x14440000; /* MB0 word 1: Tx msg with STD ID 0x511 */
#endif
CAN0->RAMn[ 0*MSG_BUF_SIZE + 0] = 0x0C400000 | 8 <ICPR[1] = 1 << (81 % 32); /* IRQ81-CHA0 0-15: clr any pending IRQ*/
S32_NVIC->ISER[(uint32_t)(CAN0_ORed_0_15_MB_IRQn) >> 5U] = (uint32_t)(1UL << ((uint32_t)(CAN0_ORed_0_15_MB_IRQn) & (uint32_t)0x1FU));
S32_NVIC->IP[81] = 0xb; /* IRQ81-CAN0 0-15: priority 10 of 0-15*/
}
int main(void)
{
unsigned int ADC_Value;
WDOG_disable(); //关闭看门狗
SOSC_init_8MHz(); //配置系统振荡器为外部8MHZ
SPLL_init_160MHz(); //使用SOSC 8MHZ配置SPLL 为160 MHz
NormalRUNmode_40MHz(); //配置系列时钟40MHz, 40MHz总线时钟
CAN0_init();
CAN0_NVIC_init_IRQs();
CAN_PORT_init();
for(;;)
{
}
return 0;
}
/*********************************************************************
* 函数原型：void CAN0_ORed_0_15_MB_IRQHandler(void)
* 功 能：CAN0中断服务器
* 输入参数：无
* 返回参数：无
*
* 其他说明：
*********************************************************************/
void CAN0_ORed_0_15_MB_IRQHandler(void)
{
unsigned char j;
if ((CAN0->IFLAG1 >> 4) & 1)
{
RxCODE = (CAN0->RAMn[ 4*MSG_BUF_SIZE + 0] & 0x07000000) >> 24; /* Read CODE field */
RxID = (CAN0->RAMn[ 4*MSG_BUF_SIZE + 1] & CAN_WMBn_ID_ID_MASK) >> CAN_WMBn_ID_ID_SHIFT ;
RxLENGTH = (CAN0->RAMn[ 4*MSG_BUF_SIZE + 0] & CAN_WMBn_CS_DLC_MASK) >> CAN_WMBn_CS_DLC_SHIFT;
for (j=0; j<2; j++) { /* Read two words of data (8 bytes) */
RxDATA[j] = CAN0->RAMn[ 4*MSG_BUF_SIZE + 2 + j];
}
RxTIMESTAMP = (CAN0->RAMn[ 0*MSG_BUF_SIZE + 0] & 0x000FFFF);
if((RxID==0x15540000)||(RxID==0x14880000))
{
CAN0_transmit_msg();
}
CAN0->IFLAG1 = 0x00000010; /* Clear CAN 0 MB 4 flag without clearing others*/
}
}