Tool/software: Code Composer Studio
Please help. I found the error for the code: and could not understand the error:
/*
* CAN bus LED controller master firmware
* Written for TI Tiva TM4C1294NCPDT
*/
#include <stdbool.h>
#include <stdint.h>
#include <math.h>
#include "inc/hw_memmap.h"
#include "inc/hw_types.h"
#include "inc/hw_can.h"
#include "inc/hw_ints.h"
#include "driverlib/can.h"
#include "driverlib/interrupt.h"
#include "driverlib/sysctl.h"
#include "driverlib/gpio.h"
#include "driverlib/uart.h"
#include "driverlib/pin_map.h"
#include "utils/uartstdio.h"
#define PI 3.14159265359f
volatile bool errFlag = 0; // transmission error flag
unsigned int sysClock; // clockspeed in hz
volatile bool rxFlag = 0; // msg recieved flag
void delay(unsigned int milliseconds) {
SysCtlDelay((sysClock / 3) * (milliseconds / 1000.0f));
}
// CAN interrupt handler
void CANIntHandler(void) {
unsigned long status = CANIntStatus(CAN1_BASE, CAN_INT_STS_CAUSE); // read interrupt status
if(status == CAN_INT_INTID_STATUS) { // controller status interrupt
status = CANStatusGet(CAN1_BASE, CAN_STS_CONTROL); // read back error bits, do something with them?
errFlag = 1;
} else if(status == 1)
{ // message object 1
CANIntClear(CAN1_BASE, 1); // clear interrupt
errFlag = 0; // clear any error flags
rxFlag = 1; // set rx flag
} else { // should never happen
UARTprintf("Unexpected CAN bus interrupt\n");
}
}
int main(void) {
tCANMsgObject msg; // the CAN message object
unsigned char msgData[8]; // 8 byte buffer for rx message data
unsigned char *msgDataPtr = (unsigned char *)&msgData; // make a pointer to msgData so we can access individual bytes
// Run from the PLL at 120 MHz.
sysClock = SysCtlClockFreqSet((SYSCTL_XTAL_25MHZ | SYSCTL_OSC_MAIN | SYSCTL_USE_PLL | SYSCTL_CFG_VCO_480), 120000000);
// Set up debugging UART
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOA); // enable UART0 GPIO peripheral
SysCtlPeripheralEnable(SYSCTL_PERIPH_UART0);
GPIOPinConfigure(GPIO_PA0_U0RX);
GPIOPinConfigure(GPIO_PA1_U0TX);
GPIOPinTypeUART(GPIO_PORTA_BASE, GPIO_PIN_0 | GPIO_PIN_1);
UARTStdioConfig(0, 115200, sysClock); // 115200 baud
// Set up CAN1
SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOB); // enable CAN1 GPIO peripheral
GPIOPinConfigure(GPIO_PB0_CAN1RX);
GPIOPinConfigure(GPIO_PB1_CAN1TX);
GPIOPinTypeCAN(GPIO_PORTB_BASE, GPIO_PIN_0 | GPIO_PIN_1);
SysCtlPeripheralEnable(SYSCTL_PERIPH_CAN1);
CANInit(CAN1_BASE);
CANBitRateSet(CAN1_BASE, sysClock, 500000);
CANIntRegister(CAN1_BASE, CANIntHandler); // use dynamic vector table allocation
CANIntEnable(CAN1_BASE, CAN_INT_MASTER | CAN_INT_ERROR | CAN_INT_STATUS);
IntEnable(INT_CAN1);
CANEnable(CAN1_BASE);
// Set up msg object
msg.ui32MsgID = 1;
msg.ui32MsgIDMask = 0;
msg.ui32Flags = MSG_OBJ_RX_INT_ENABLE | MSG_OBJ_USE_ID_FILTER;
msg.ui32MsgLen = sizeof(msgDataPtr);
msg.pui8MsgData = msgDataPtr;
CANMessageSet(CAN1_BASE, 1, &msg, MSG_OBJ_TYPE_RX);
unsigned int t = 0; // loop counter
float freq = 0.3; // frequency scaler
unsigned int colour[3];
float intensity;
while(1) {
if(rxFlag) { // rx interrupt has occured
msg.pui8MsgData = msgData; // set pointer to rx buffer
CANMessageGet(CAN1_BASE, 1, &msg, 0); // read CAN message object 1 from CAN peripheral
rxFlag = 0; // clear rx flag
if(msg.ui32Flags & MSG_OBJ_DATA_LOST) { // check msg flags for any lost messages
UARTprintf("CAN message loss detected\n");
}
// read in colour data from rx buffer (scale from 0-255 to 0-0xFFFF for LED driver)
colour[0] = msgData[0] * 0xFF;
colour[1] = msgData[1] * 0xFF;
colour[2] = msgData[2] * 0xFF;
intensity = msgData[3] / 255.0f; // scale from 0-255 to float 0-1
// write to UART for debugging
UARTprintf("Received colour\tr: %d\tg: %d\tb: %d\ti: %d\n", msgData[0], msgData[1], msgData[2], msgData[3]);
}
return 0;
}
The error is :
