LINtongxun.rar_LIN通讯_lin_lin 通讯

/*define*/ #define MAX_DATA 1 // Max bytes lin frame data #define SCI_BAUDRATE 19200 // SCI baud rate #define SCI_CLOCK 200 0000 // Bus clock in Hz #define EVER (;;) #define FALSE -1 #define TRUE 0 #define DEBOUNCE 1 /* 20.5ms x (1+1) = 41ms */ #define LOW_POWER 195 /* 20.5ms x (195+1) = 4s */ l_bool sleep_mode = 0; static l_u16 previous_start_time = 0; /* Wraps around but usage is safe */ enum lin_state { IDLE, _BREAK, SYNCH, PROTECTED_IDENTIFIER, DATA_0, DATA_1, DATA_2, DATA_3, DATA_4, DATA_5, DATA_6, DATA_7, CHECKSUM }; struct message { unsigned char identifier; unsigned char data_field[MAX_DATA]; }; struct frame { unsigned char protected_id; unsigned char data[MAX_DATA]; unsigned char check; enum lin_state state; unsigned char error; }; struct frame rx; // Functions ///////////////////////////////////////////////////////////////////////////////////////// void LINInit(void); Bool LINGetMsg(Bool get_data, struct message *msg); Bool LINSendMsg(Bool master, Bool send_data, struct message msg); enum lin_state LINCheckState(void); /*LIN初始化*/ void LINInit(void) { int sbr,i; sbr=(SCI_CLOCK/SCI_BAUDRATE/16); //设置波特率 SCI1BDH =(unsigned char)(sbr>>8); SCI1BDL =(unsigned char)sbr; SCI1C2 =0x2C; //SCI中断使能 // Break character is 13 or 14 bit long SCI1S2=0x04; // 设置中断字节长度 （13或14位） // Initializes LIN receive frames rx.protected_id=0; //初始化LIN的接收帧 rx.state=IDLE; rx.error=0; rx.check=0; for (i=0;i<MAX_DATA;I++) msg- FALSE; return PROTECTED_IDENTIFIER) if (get_data) { if(rx.state == CHECKSUM) { for(i = 0; i < MAX_DATA; i++) msg->data_field[i] = rx.data[i]; rx.state = IDLE; } else for(i = 0; i < MAX_DATA; i++) msg->data_field[i] = 0; } return(TRUE); } /*SCI接收中断子程序*/ interrupt void SCI1_RX(void) // SCI 的接收中断子程序 { if(!LINGetChar()) // 如果LIN 未接收到字符 { rx.error = 1; rx.state = IDLE; } } /*LIN发送字符子程序*/ Bool LINSendChar(Bool brk, unsigned char ch) // LIN的发送字符子程序 { // Waits until transmit data registry is empty (TDRE=1) while(!(SCI1S1&0x80)) ; // If break field, transmits one break character (13-14 bits of dominant value) if(brk) { SCI1C2 |= 0x01; SCI1C2 &= ~0x01; } else SCI1D = ch; return(TRUE); /*LIN 发送校验子程序*/ Bool LINCheckSend(enum lin_state status, unsigned char val) //LIN发送校验发送子程序 { // While until sci data has been received while(rx.state < status) if(rx.error) return(FALSE); switch(status) { case _BREAK: case SYNCH: break; case PROTECTED_IDENTIFIER: if(rx.protected_id != val) return(FALSE); break; case DATA_0: case DATA_1: case DATA_2: case DATA_3: case DATA_4: case DATA_5: case DATA_6: case DATA_7: if(rx.data[status-DATA_0] != val) return(FALSE); break; case CHECKSUM: if(rx.check != val) return(FALSE); break; } return(TRUE); } /*LIN发送帧子程序*/ Bool LINSendMsg(Bool master, Bool send_data, struct message msg) // LIN 发送帧子程序 { unsigned char check_sum, parity_id, i; rx.error = 0; if(master) { // Sends break feald if(!LINSendChar(TRUE, 0x00)) return(FALSE); // Check break sending if(!LINCheckSend(_BREAK, 0x00)) return(FALSE); // Sends synch feald if(!LINSendChar(FALSE, 0x55)) return(FALSE); // Checks synch sending if(!LINCheckSend(SYNCH, 0x55)) return(FALSE); parity_id=LINCalcParity(msg.identifier); // Sends protected identifier field if(!LINSendChar(FALSE, parity_id)) return(FALSE); // Checks protected identifier sending if(!LINCheckSend(PROTECTED_IDENTIFIER, parity_id)) return(FALSE); } if(send_data) { for(i=0; i < MAX_DATA; i++) { // Sends data field if(!LINSendChar(FALSE, msg.data_field[i])) return(FALSE); // Checks data sending if(!LINCheckSend(DATA_0+i, msg.data_field[i])) return(FALSE); } check_sum = LINCalcChecksum(msg.data_field); // Sends checksum field if(!LINSendChar(FALSE, check_sum)) return(FALSE); // Checks checksum sending if(!LINCheckSend(CHECKSUM, check_sum)) return(FALSE); rx.state = IDLE; } return(TRUE); } /*LIN 校验状态*/ enum lin_state LINCheckState(void) // LIN 的校验状态(结果) return rx.state; } /*校验是否为睡眠模式*/ void CheckLowPower(void) { l_u16 status; status = l_ifc_read_status_i1(); /* Sleep command received? */ if ((status & 0x0008)== L_SLEEP_REQUEST) /* 判断是否为睡眠模式*/ { LIN_EN_PIN = 0; /* yes, disable MC33399 LIN interface turn off */ /* LT1121 to reache low power consumption */ } if ((status & 0x00FF) == 0x00) /* No activity on LIN? */ { low_power_delay--; /* yes, decrement the counter */ } else { low_power_delay = LOW_POWER; } if (low_power_delay == 0) /* no activity on LIN for 4 seconds? */ { LIN_EN_PIN = 0; /* yes, disable MC33399 LIN interface turn off */ /* LT1121 to reache low power consumption */ } } /*校验返回值*/ void Check (l_bool return_value) { if (return_value) { NodeFailure(); } } /*返回值不正确进入死循环*/ void NodeFailure (void) { for EVER /* To avoid warning message */ { /* forever */ } } /*进入睡眠模式 */void GotoSleep (void) { while (l_sch_tick_i1() != 1) /* one round */ { BusyWaitUntilNextPeriod(); } l_ifc_goto_sleep_i1(); /* send the sleep commnand */ sleep_mode = 1; /* set the sleep mode flag */ } void BusyWaitUntilNextPeriod (void) { l_u16 t_now; /* The time counter value for now */ l_u16 elapsed; /* Time elapsed since previous ideal start time */ do { #ifdef PET_WATCHDOG PET_WATCHDOG(); #endif t_now = l_get_us_counter(); elapsed = (l_u16) (t_now - previous_start_time); } while (elapsed < HW_DELAY); previous_start_time += HW_DELAY; /* This construct avoids time drift, previous_start_time