我在尝试创建一个在函数内调用“__delay_ms()”的库时遇到一些麻烦。进行了广泛的搜索，但找不到解决方案，也没有找到其他解释。我正在使用 XC8 v2.30 MPLAB 5.45。
我有一个主要函数，其中包含标题“qc3.h”：
#include <xc.h> // include standard header file
// set Config bits
#pragma config FOSC=INTOSC, PLLEN=OFF, WDTE=OFF, MCLRE=ON,
#pragma config CLKOUTEN=OFF, IESO=OFF, FCMEN=OFF,CP=OFF, CPD=OFF,BOREN=OFF
#pragma config WRT=OFF,STVREN=ON,BORV=LO,LVP=OFF
// Definitions
#define _XTAL_FREQ 500000 // this is used by the __delay_ms(xx) and __delay_us(xx) functions
#include "qc3.h"
#define LED PORTAbits.RA2
//**********************************************************************************
//***************** main routine ***********************************************
//**********************************************************************************
void main ( )
{
// set up oscillator control register
OSCCONbits.SPLLEN=0; // PLL is disabled
OSCCONbits.IRCF=0x07; //set OSCCON IRCF bits to select OSC frequency=500Khz
OSCCONbits.SCS=0x02; //set the SCS bits to select internal oscillator block
// OSCON should be 0x7Ah now.
// Set up I/O pins
ANSELAbits.ANSELA=0; // set all analog pins to digital I/O
ADCON0bits.ADON=0; // turn ADC off
DACCON0bits.DACEN=0; // turn DAC off
// PORT A Assignments (0 = OUTPUT, 1 = INPUT)
TRISAbits.TRISA0 = 0; // RA0 = nc
TRISAbits.TRISA1 = 0; // RA1 = nc
TRISAbits.TRISA2 = 0; // RA2 = nc
TRISAbits.TRISA3 = 0; // RA3 = nc (MCLR)
TRISAbits.TRISA4 = 0; // RA4 = nc
TRISAbits.TRISA5 = 0; // RA5 = nc
QC3_Initialize(); // incia protocolo para handshake
while(1)
{
__delay_ms(100);
LED = 1;
__delay_ms(100);
LED = 0;
}
}
qc3.h：
#ifndef QC3_H_ /* Include guard */
#define QC3_H_
/**
Section: Included Files
*/
#include <xc.h>
#include <stdint.h>
#include <stdbool.h>
#ifdef __cplusplus // Provide C++ Compatibility
extern "C" {
#endif
//Quick Charge 3 Pin defines
#define DP_HIGH PORTAbits.RA0
#define DM_HIGH PORTAbits.RA1
#define DP_LOW PORTAbits.RA5
#define DM_LOW PORTAbits.RA4
void QC3_Initialize(void);
//void onewireWriteBit(int b);
//unsigned char onewireReadBit();
//unsigned char onewireInit();
//unsigned char onewireReadByte();
//void onewireWriteByte(char data);
//unsigned char onewireCRC(unsigned char* addr, unsigned char len);
#ifdef __cplusplus // Provide C++ Compatibility
}
#endif
#endif
qc3.c：
#include "qc3.h"
void QC3_Initialize(void) {
__delay_ms(150);
DP_HIGH = 0;
}
错误：
make -f nbproject/Makefile-default.mk SUBPROJECTS= .build-conf
make[1]: Entering directory 'D:/Google Drive/Projetos/Pedais/Fonte para pedais isolada/QUICK CHARGE/PIC'
make -f nbproject/Makefile-default.mk dist/default/production/PIC.production.hex
make[2]: Entering directory 'D:/Google Drive/Projetos/Pedais/Fonte para pedais isolada/QUICK CHARGE/PIC'
"D:\Program Files\Microchip\xc8\v2.30\bin\xc8-cc.exe" -mcpu=12F1840 -c -mdfp="D:/Program Files/Microchip/MPLABX/v5.45/packs/Microchip/PIC12-16F1xxx_DFP/1.2.63/xc8" -fno-short-double -fno-short-float -O0 -fasmfile -maddrqual=ignore -xassembler-with-cpp -I"head_and_lib" -mwarn=-3 -Wa,-a -DXPRJ_default=default -msummary=-psect,-class,+mem,-hex,-file -ginhx032 -Wl,--data-init -mno-keep-startup -mno-osccal -mno-resetbits -mno-save-resetbits -mno-download -mno-stackcall -std=c99 -gdwarf-3 -mstack=compiled:auto:auto -o build/default/production/head_and_lib/qc3.p1 head_and_lib/qc3.c
"D:\Program Files\Microchip\xc8\v2.30\bin\xc8-cc.exe" -mcpu=12F1840 -c -mdfp="D:/Program Files/Microchip/MPLABX/v5.45/packs/Microchip/PIC12-16F1xxx_DFP/1.2.63/xc8" -fno-short-double -fno-short-float -O0 -fasmfile -maddrqual=ignore -xassembler-with-cpp -I"head_and_lib" -mwarn=-3 -Wa,-a -DXPRJ_default=default -msummary=-psect,-class,+mem,-hex,-file -ginhx032 -Wl,--data-init -mno-keep-startup -mno-osccal -mno-resetbits -mno-save-resetbits -mno-download -mno-stackcall -std=c99 -gdwarf-3 -mstack=compiled:auto:auto -o build/default/production/source/ISOPOWER.p1 source/ISOPOWER.c
make[2]: *** [build/default/production/head_and_lib/qc3.p1] Error 1
make[2]: *** Waiting for unfinished jobs....
head_and_lib/qc3.c:6:3: error: use of undeclared identifier '_XTAL_FREQ'
__delay_ms(150);
^
D:/Program Files/Microchip/MPLABX/v5.45/packs/Microchip/PIC12-16F1xxx_DFP/1.2.63/xc8\pic\include\pic.h:101:51: note: expanded from macro '__delay_ms'
#define __delay_ms(x) _delay((unsigned long)((x)*(_XTAL_FREQ/4000.0)))
^
1 error generated.
(908) exit status = 1
nbproject/Makefile-default.mk:123: recipe for target 'build/default/production/head_and_lib/qc3.p1' failed
make[1]: *** [.build-conf] Error 2
make: *** [.build-impl] Error 2
make[2]: Leaving directory 'D:/Google Drive/Projetos/Pedais/Fonte para pedais isolada/QUICK CHARGE/PIC'
nbproject/Makefile-default.mk:91: recipe for target '.build-conf' failed
make[1]: Leaving directory 'D:/Google Drive/Projetos/Pedais/Fonte para pedais isolada/QUICK CHARGE/PIC'
nbproject/Makefile-impl.mk:39: recipe for target '.build-impl' failed
BUILD FAILED (exit value 2, total time: 913ms)
编译器抱怨（使用未声明的标识符“_XTAL_FREQ”），但标头在#define _XTAL_FREQ 500000之后声明。为什么？
如果我删除该功能的延迟：
void QC3_Initialize(void) {
__delay_ms(150);
DP_HIGH = 0;
构建成功
所以。如果从未声明过 QC3.c（即使在“.h”标头中），“何时”“调用”QC3.c？
如果“.c”包含“.h”，为什么我要声明“.h”？难道不应该反过来吗？或者至少是“.h” 包含“.c”？
看似基本的东西，但它让我大吃一惊
谢谢你
您在包含
_XTAL_FREQmain()__delay_ms()单独的翻译单元）中调用
qc3.c，所以 that's 需要存在该定义。
最简单的解决方法可能是在
qc3.h你必须在.c文件中给出_XTAL_FREQ，然后你才能得到。