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Question

我不知道我發現了以下錯誤：

proc1.o: In function `procEx1': 
/cygdrive/c/armprojects/projekt/motor/proc1.c:45: undefined reference to `motorTest_test' 
collect2: ld returned 1 exit status 
make: *** [main.hex] Error 1 

我檢查以下線程對這個問題：

• Undefined reference gcc
• Why am I getting a gcc "undefined reference" error trying to create shared objects?

這是我的輸出：

13:46:46 **** Build of configuration Default for project motor **** 
make all 
make[1]: Entering directory `/cygdrive/c/armprojects/projekt/motor/startup' 
rm -f .depend 
arm-elf-gcc -c -mcpu=arm7tdmi -I . -DEL -DGCC -mthumb-interwork -DLPC2148 -Os - gdwarf-2 -Wall -Wcast-align -Wcast-qual -Wimplicit -Wnested-externs -Wpointer-arith -Wswitch  -Wreturn-type -Wa,-ahlms=consol.lst -o consol.o consol.c 
arm-elf-gcc -c -mcpu=arm7tdmi -I . -DEL -DGCC -mthumb-interwork -DLPC2148 -Os - gdwarf-2 -Wall -Wcast-align -Wcast-qual -Wimplicit -Wnested-externs -Wpointer-arith -Wswitch -Wreturn-type -Wa,-ahlms=framework.lst -o framework.o framework.c 
framework.c: In function 'exceptionHandlerInit': 
framework.c:201: warning: pointer targets in assignment differ in signedness 
arm-elf-gcc -c -mcpu=arm7tdmi -I . -DEL -DGCC -mthumb-interwork -DLPC2148 -x   assembler-with-cpp -gstabs -Wa,-alhms=startup.lst -o startup.o startup.S 
arm-elf-ar cr libea_startup_thumb.a consol.o framework.o startup.o 
arm-elf-ranlib libea_startup_thumb.a 
make[1]: Leaving directory `/cygdrive/c/armprojects/projekt/motor/startup' 
make[1]: Entering directory `/cygdrive/c/armprojects/projekt/motor/LCD' 
rm -f .depend 
arm-elf-gcc -c -mcpu=arm7tdmi -I . -DEL -DGCC -mthumb-interwork -DLPC2148 -O0 - gdwarf-2 -Wall -Wcast-align -Wcast-qual -Wimplicit -Wnested-externs -Wpointer-arith -Wswitch  -Wreturn-type -Wa,-ahlms=LCD.lst -o LCD.o LCD.c 
arm-elf-ar cr lib_LCD.a LCD.o 
arm-elf-ranlib lib_LCD.a 
make[1]: Leaving directory `/cygdrive/c/armprojects/projekt/motor/LCD' 
make[1]: Entering directory `/cygdrive/c/armprojects/projekt/motor/interrupt' 
rm -f .depend 
arm-elf-gcc -c -mcpu=arm7tdmi -I . -DEL -DGCC -mthumb-interwork -DLPC2148 -Os - gdwarf-2 -Wall -Wcast-align -Wcast-qual -Wimplicit -Wnested-externs -Wpointer-arith -Wswitch  -Wreturn-type -Wa,-ahlms=interrupt_timer.lst -o interrupt_timer.o interrupt_timer.c 
arm-elf-gcc -c -mcpu=arm7tdmi -I . -DEL -DGCC -mthumb-interwork -DLPC2148 -Os - gdwarf-2 -Wall -Wcast-align -Wcast-qual -Wimplicit -Wnested-externs -Wpointer-arith -Wswitch  -Wreturn-type -Wa,-ahlms=interrupt_tacho.lst -o interrupt_tacho.o interrupt_tacho.c 
arm-elf-ar cr lib_interrupt.a interrupt_timer.o interrupt_tacho.o 
arm-elf-ranlib lib_interrupt.a 
make[1]: Leaving directory `/cygdrive/c/armprojects/projekt/motor/interrupt' 
rm -f .depend 
arm-elf-gcc -c -mcpu=arm7tdmi -mthumb-interwork -I./startup -DEL -DGCC -mthumb-interwork  -mthumb -DTHUMB_CSTART -DTHUMB_INTERWORK -mthumb-interwork -DLPC2148 -O0 -gdwarf-2 -Wall - Wcast-align -Wcast-qual -Wimplicit -Wnested-externs -Wpointer-arith -Wswitch -Wreturn-type  -Wa,-ahlms=main.lst -o main.o main.c 
arm-elf-gcc -c -mcpu=arm7tdmi -mthumb-interwork -I./startup -DEL -DGCC -mthumb-interwork  -mthumb -DTHUMB_CSTART -DTHUMB_INTERWORK -mthumb-interwork -DLPC2148 -O0 -gdwarf-2 -Wall - Wcast-align -Wcast-qual -Wimplicit -Wnested-externs -Wpointer-arith -Wswitch -Wreturn-type  -Wa,-ahlms=proc1.lst -o proc1.o proc1.c 
motor/motor_test.h:18: warning: 'duty1' defined but not used 
motor/motor_test.h:19: warning: 'duty2' defined but not used 
arm-elf-gcc -c -mcpu=arm7tdmi -mthumb-interwork -I./startup -DEL -DGCC -mthumb-interwork  -mthumb -DTHUMB_CSTART -DTHUMB_INTERWORK -mthumb-interwork -DLPC2148 -O0 -gdwarf-2 -Wall - Wcast-align -Wcast-qual -Wimplicit -Wnested-externs -Wpointer-arith -Wswitch -Wreturn-type  -Wa,-ahlms=proc2.lst -o proc2.o proc2.c 
arm-elf-gcc -c -mcpu=arm7tdmi -mthumb-interwork -I./startup -DEL -DGCC -mthumb-interwork  -mthumb -DTHUMB_CSTART -DTHUMB_INTERWORK -mthumb-interwork -DLPC2148 -O0 -gdwarf-2 -Wall - Wcast-align -Wcast-qual -Wimplicit -Wnested-externs -Wpointer-arith -Wswitch -Wreturn-type  -Wa,-ahlms=proc3.lst -o proc3.o proc3.c 
arm-elf-gcc main.o proc1.o proc2.o proc3.o startup/libea_startup_thumb.a  pre_emptive_os/pre_emptive_os.a LCD/lib_LCD.a interrupt/lib_interrupt.a -I./startup - mcpu=arm7tdmi -mthumb-interwork -mthumb-interwork -nostartfiles -T  build_files/link_32k_512k_rom.ld -o main.elf -Wl,-Map=main.map,--cref 
proc1.o: In function `procEx1': 
/cygdrive/c/armprojects/projekt/motor/proc1.c:45: undefined reference to  `motorTest_test' 
collect2: ld returned 1 exit status 
make: *** [main.hex] Error 1 

13:46:52 Build Finished (took 6s.46ms) 

如果你願意，你可以在結帳我的倉庫： http://dt3-robotlego-2012ht-white.googlecode.com/svn/branches/motor/Project12/

下面是一些我的代碼（相關部分）：
proc1.c

/* 
* proc1.c 
* 
* Created on: 31 okt 2011 
*  Author: Tommy 
*/ 

/***************************************************************************** 
* Process 1 
****************************************************************************/ 
#include "pre_emptive_os/api/osapi.h" 
#include "general.h" 
#include "startup/lpc2xxx.h" 
#include "startup/printf_P.h" 
#include "startup/ea_init.h" 
#include "startup/consol.h" 
#include "startup/config.h" 
#include "startup/framework.h" 
#include "utils/utils.h" 
#include "LCD/LCD.h" 
#include "motor/motor_test.h" 

extern long const delayshort; 
extern long const delaylong; 

extern tCntSem mutexLCD; 

/***************************************************************************** 
* Function prototypes 
****************************************************************************/ 
void LCD_clearDisplay(void); 

/****************************************************************************/ 

void 
procEx1(void* arg) 
{ 
    tU8 error; 

    for (;;) { // QUESTION: why use for-loop? 

     osSemTake(&mutexLCD, 0, &error); 

     // REMARK: doesn't work at the moment... issues including runPwm() 
     motorTest_test(); 

     osSemGive(&mutexLCD, &error); 

     osSleep(100); 
    } 

} 

void LCD_clearDisplay(void) { 
    delay(delayshort); 
    send_instruction(1); //clears the display 
    delay(delaylong); 
    send_instruction(2); //the cursor is moved to the first position 
} 

motor_test.h

/****************************************************************************** 
* Includes 
*****************************************************************************/ 
#include "motor.h" 

/****************************************************************************** 
* Defines 
*****************************************************************************/ 
#define TASK    9  // task 1 - use circulary loop 
            // task 2 - use constant PWM signal 
            // ... 
#define RUN_SETPWM_IN_LOOP 1  // dictates whether setPwmDutyPercentx(tU32) should be run outside the "TASK conditional statement" 

/***************************************************************************** 
* Global variables 
****************************************************************************/ 
static tU32 duty1; 
static tU32 duty2; 


/****************************************************************************** 
* Prototypes 
*****************************************************************************/ 
void motorTest_test(); 
void dev_run(tU32 duty1, tU32 duty2); 
void pwm_motor_init(); 
void pwm_motor_run(tU32 duty1, tU32 duty2); 
void change_mode(short mode); 

motor_test.c

#include "motor_test.h" 

/****************************************************************************** 
* Functions 
*****************************************************************************/ 
void motorTest_test() { 
    init(); 
    dev_run(duty1, duty2); 
} 



// dev function - not used in release 
// COMMENT: PWM signal is continuously generated when the setPwmDutyPercent(tU32) function is called, no need to endlessly iterate the calls 
// EDIT: seems like you need to iterate over the setPwmDutyPercent(tU32) functions afterall... 
// COMMENT: the duty sets the speed of the motor driver 
//   the value that can be set is 0-10000 
//   a higher value means a lower speed, conversely a low value means a higher speed 
void dev_run(tU32 duty1, tU32 duty2) { 
    //wait 10 ms 
    //delayMs(10); 

    //wait 100 ms 
    //delayMs(100); 

    // COMMENT: try running without delays 
    //   seems to work fine.. 

    while (1) { 

     //set frequency value 
     if (RUN_SETPWM_IN_LOOP == 1) { 
      setPwmDutyPercent1(duty1); 
      setPwmDutyPercent2(duty2); 
     } 

     // delayMs(10); 

     switch (TASK) { 
     case 1: { 
      //update duty cycle (0.00 - 100.00%, in steps of 0.10%) 
      duty1 += 10; 
      if (duty1 > 10000) 
       duty1 = 0; 
      break; 
     } 
     case 2: { 
      duty1 = 0; 
      duty2 = 8500; 
      // COMMENT: slowest speed = 8500 duty 
      //   fastest speed = 0 duty 
      break; 
     } 
     case 3: { // left 
      duty1 = 6000; 
      duty2 = 8000; 
      break; 
     } 
     case 4: { // right 
      duty1 = 8000; 
      duty2 = 6000; 
      break; 
     } 
     case 5: { 
      duty1 = 6000; 
      duty2 = 6000; 
      break; 
     } 

     case 6: { 
      short delay = 1; 
      short duty_vals = 6000; 
      short section[3] = { 1, 0, 0 }; 

      if (section[0] == 1) { 
       setMode1(MODE_FORWARD); 
       setMode2(MODE_FORWARD); 
       duty1 = duty_vals; 
       duty2 = duty_vals; 
       setPwmDutyPercent1(duty1); 
       setPwmDutyPercent2(duty2); 
       //delayMs(0); 
       delay_millis(delay); 
      } 

      if (section[1] == 1) { 
       setMode1(MODE_BRAKE); 
       setMode2(MODE_BRAKE); 
       setPwmDutyPercent1(duty1); 
       setPwmDutyPercent2(duty2); 
       delay_millis(delay); 
      } 

      if (section[2] == 1) { 
       setMode1(MODE_REVERSE); 
       setMode2(MODE_REVERSE); 
       duty1 = duty_vals; 
       duty2 = duty_vals; 
       setPwmDutyPercent1(duty1); 
       setPwmDutyPercent2(duty2); 
       delay_millis(delay); 
      } 
      break; 
     } 
     case 7: { 
      pwm_motor_init(); 
      duty1 = 6000; 
      duty2 = 6000; 

      //delayMs(10); 
      delay_millis(10); 

      pwm_motor_run(duty1, duty2); 
      break; 
     } 
     case 8: { 


      setMode1(MODE_FORWARD); 
      setMode2(MODE_FORWARD); 

      delay_millis(700); 

      duty1 = 7000; 
      duty2 = 7000; 


      setMode1(MODE_REVERSE); 
      setMode2(MODE_REVERSE); 

      delay_millis(700); 

      duty1 = 1000; 
      duty2 = 1000; 

      break; 
     } 

     case 9: { 
      duty1 = 0; 
      duty2 = 0; 
      break; 
     } 

     } 
    } 
} 

/***************************************************************************** 
* Temporary developer functions 
****************************************************************************/ 
void pwm_motor_init() { 
    setMode1(MODE_FORWARD); 
    setMode2(MODE_FORWARD); 

    delay_millis(10); 
} 

void pwm_motor_run(tU32 duty1, tU32 duty2) { 
    setPwmDutyPercent1(duty1); 
    setPwmDutyPercent2(duty2); 

    while(1) { 
     change_mode(MODE_FORWARD); 
     change_mode(MODE_BRAKE); 
     change_mode(MODE_REVERSE); 
     change_mode(MODE_BRAKE); 
    } 
} 

void change_mode(short mode) { 
    setMode1(mode); 
    setMode2(mode); 
    delay_millis(10); 
} 

Answer 1

確保將所有C源包括到CSRCS變量your makefile中。然後構建系統會知道它也必須編譯該文件，並將生成的對象包含到鏈接中。