stm32的超声波数据采集显示问题

homelybos · 发表于 2013-3-13 10:25:20

主程序代码

#include "LCD1602.h"

#include "ultrasonic.h"

#include"delay.h"

int main()

{

float temp;

char DisNum[16];

SystemInit();

delay_init(72);

LCD1602_Init();

Ultran_Init();

while(1)

{

Ultra_Ranging(&temp);

LCD1602Clear();

sprintf(DisNum,"%1.4f",temp);

LCD1602WriteEnStr(0,0,(u8 *)DisNum);

// delay_ms(500);

}

}
调试时出现警告，错误问题。需要怎么解决？
错误显示
main.c(11): warning:  #223-D: function "LCD1602_Init" declared implicitly
main.c: LCD1602_Init();
main.c: ^
main.c(18): warning:  #223-D: function "LCD1602Clear" declared implicitly
main.c: LCD1602Clear();
main.c: ^
main.c(19): warning:  #223-D: function "sprintf" declared implicitly
main.c: sprintf(DisNum,"%1.4f",temp);
main.c: ^
main.c(20): warning:  #223-D: function "LCD1602WriteEnStr" declared implicitly
main.c: LCD1602WriteEnStr(0,0,(u8 *)DisNum);

ULTRASONIC.axf: Error: L6218E: Undefined symbol LCD1602Clear (referred from main.o).
ULTRASONIC.axf: Error: L6218E: Undefined symbol LCD1602WriteEnStr (referred from main.o).
ULTRASONIC.axf: Error: L6218E: Undefined symbol LCD1602_Init (referred from main.o).
ULTRASONIC.axf: Not enough information to list image symbols.
ULTRASONIC.axf: Finished: 1 information, 0 warning and 3 error messages.
Target not created