存放路径：在PICC软件hi-tech安装目录下，?:\Microchip\cc8.05\include，找到pic1687xa.h，里面即有
以下是头文件内容及详细注释：
/*
* Header file for the Microchip
* PIC 16F873A chip
* PIC 16F874A chip
* PIC 16F876A chip
* PIC 16F877A chip
* Midrange Microcontroller
*/
#if defined(_16F874A) || defined(_16F877A)
#define __PINS_40
#endif
static volatile unsigned char INDF @ 0x00; //间接寻址寄存器
static volatile unsigned char TMR0 @ 0x01; //定时器0
static volatile unsigned char PCL @ 0x02; //低8位程序计数器
static volatile unsigned char STATUS @ 0x03; //程序状态寄存器
static unsigned char FSR @ 0x04; //特殊功能寄存器
static volatile unsigned char PORTA @ 0x05; //端口A寄存器
static volatile unsigned char PORTB @ 0x06; //端口B寄存器
static volatile unsigned char PORTC @ 0x07; //端口C寄存器
#ifdef __PINS_40
static volatile unsigned char PORTD @ 0x08; //端口D寄存器
static volatile unsigned char PORTE @ 0x09; //端口E寄存器
#endif
static unsigned char PCLATH @ 0x0A; //高5位程序计数器
static volatile unsigned char INTCON @ 0x0B; //中断控制寄存器
static volatile unsigned char PIR1 @ 0x0C; //中断标志寄存器PIR1
static volatile unsigned char PIR2 @ 0x0D; //中断标志寄存器PIR2
static volatile unsigned char TMR1L @ 0x0E; //低字节计数寄存器
static volatile unsigned char TMR1H @ 0x0F; //高字节计数寄存器
static volatile unsigned char T1CON @ 0x10; //TMR1控制寄存器
static volatile unsigned char TMR2 @ 0x11; //定时/计数器TMR2
static volatile unsigned char T2CON @ 0x12; //TMR2控制寄存器
static volatile unsigned char SSPBUF @ 0x13; //收/发数据缓冲器
static volatile unsigned char SSPCON @ 0x14; //同步串口控制寄存器，对MSSP模块的功能和指标进行设置和定义
static volatile unsigned char CCPR1L @ 0x15; //捕获/比较/PWM寄存器低字节
static volatile unsigned char CCPR1H @ 0x16; //捕获/比较/PWM寄存器低字节
static volatile unsigned char CCP1CON @ 0x17; //CCP1CON寄存器
static volatile unsigned char RCSTA @ 0x18; //USART接收控制兼状态寄存器
static volatile unsigned char TXREG @ 0x19; //USART发生缓冲器
static volatile unsigned char RCREG @ 0x1A; //USART接收缓冲器
static volatile unsigned char CCPR2L @ 0x1B; //捕获/比较/PWM寄存器低字节
static volatile unsigned char CCPR2H @ 0x1C; //捕获/比较/PWM寄存器低字节
static volatile unsigned char CCP2CON @ 0x1D; //CCP2CON寄存器
static volatile unsigned char ADRESH @ 0x1E; //ADC转换结果寄存器高字节
static volatile unsigned char ADCON0 @ 0x1F; //A/D转换器开关位
/* bank 1 registers */
static unsigned char bank1 OPTION @ 0x81; //选择寄存器，用于配置TMR0/WDT预分频系数、外部INT中断、TMR0和端口B的弱上拉。
static volatile unsigned char bank1 TRISA @ 0x85; //A口方向寄存器
static volatile unsigned char bank1 TRISB @ 0x86; //B口方向寄存器
static volatile unsigned char bank1 TRISC @ 0x87; //C口方向寄存器
#ifdef __PINS_40
static volatile unsigned char bank1 TRISD @ 0x88; //D口方向寄存器
static volatile unsigned char bank1 TRISE @ 0x89; //E口方向寄存器
#endif
static volatile unsigned char bank1 PIE1 @ 0x8C; //中断允许寄存器PIE1
static volatile unsigned char bank1 PIE2 @ 0x8D; //中断允许寄存器PIE2
static volatile unsigned char bank1 PCON @ 0x8E; //电源控制状态寄存器
static volatile unsigned char bank1 SSPCON2 @ 0x91; //MSSP控制寄存器2
static volatile unsigned char bank1 PR2 @ 0x92; //TMR2周期寄存器
static volatile unsigned char bank1 SSPADD @ 0x93; //同步串口地址寄存器
static volatile unsigned char bank1 SSPSTAT @ 0x94; //同步串口状态寄存器
static volatile unsigned char bank1 TXSTA @ 0x98; //USART发生控制兼状态寄存器
static volatile unsigned char bank1 SPBRG @ 0x99; //USART波特率发生器初值寄存器
static volatile unsigned char bank1 CMCON @ 0x9C; //比较控制寄存器
static volatile unsigned char bank1 CVRCON @ 0x9D; //比较电压参考控制寄存器
static volatile unsigned char bank1 ADRESL @ 0x9E; //ADC转换结果寄存器低字节
static volatile unsigned char bank1 ADCON1 @ 0x9F; //ADC控制寄存器ADCON1
/* bank 2 registers */
static volatile unsigned char bank2 EEDATA @ 0x10C; //EEPROM数据寄存器低字节
static volatile unsigned char bank2 EEADR @ 0x10D; //EEPROM地址寄存器低字节
static volatile unsigned char bank2 EEDATH @ 0x10E; //EEPROM数据寄存器高字节
static volatile unsigned char bank2 EEADRH @ 0x10F; //EEPROM地址寄存器高字节
/* bank 3 registers */
static volatile unsigned char bank3 EECON1 @ 0x18C; //EEPROM控制寄存器1
static volatile unsigned char bank3 EECON2 @ 0x18D; //EEPROM控制寄存器2
//* STATUS bits状态寄存器 */
static volatile bit IRP @ (unsigned)&STATUS*8+7; //寄存器bank选择位(用于间接寻址）。0:bank0,1;1:bank2,3
static volatile bit RP1 @ (unsigned)&STATUS*8+6; //寄存器bank选择位(用于直接寻址）
PR1:PR0:00:BANK0;01:BANK1;10:BANK2;11BANK3.
static volatile bit RP0 @ (unsigned)&STATUS*8+5; //
static volatile bit TO @ (unsigned)&STATUS*8+4; //超时位。0：WDT超时发生；1：上电后，执行了CLRWDT或者SLEEP指令
static volatile bit PD @ (unsigned)&STATUS*8+3; //掉电标志位。0：执行完SLEEP指令；1：上电后或者执行CLRWDT指令
static volatile bit ZERO @ (unsigned)&STATUS*8+2; //零标志位。0：算术或逻辑操作结果不为0；1：反之。
static volatile bit DC @ (unsigned)&STATUS*8+1; //数字进位/退位标志位。0：结果的低4位没有发生进位；1：反之。
static volatile bit CARRY @ (unsigned)&STATUS*8+0; //进位/退位标志位。0：结果的高4位没有发生进位；1：反之。
/* PORTA bits */
static volatile bit RA5 @ (unsigned)&PORTA*8+5; //RA5
static volatile bit RA4 @ (unsigned)&PORTA*8+4; //RA4
static volatile bit RA3 @ (unsigned)&PORTA*8+3; //RA3
static volatile bit RA2 @ (unsigned)&PORTA*8+2; //RA2
static volatile bit RA1 @ (unsigned)&PORTA*8+1; //RA1
static volatile bit RA0 @ (unsigned)&PORTA*8+0; //RA0
/* PORTB bits */
static volatile bit RB7 @ (unsigned)&PORTB*8+7; //RB7
static volatile bit RB6 @ (unsigned)&PORTB*8+6; //RB6
static volatile bit RB5 @ (unsigned)&PORTB*8+5; //RB5
static volatile bit RB4 @ (unsigned)&PORTB*8+4; //RB4
static volatile bit RB3 @ (unsigned)&PORTB*8+3; //RB3
static volatile bit RB2 @ (unsigned)&PORTB*8+2; //RB2
static volatile bit RB1 @ (unsigned)&PORTB*8+1; //RB1
static volatile bit RB0 @ (unsigned)&PORTB*8+0; //RB0
/* PORTC bits */
static volatile bit RC7 @ (unsigned)&PORTC*8+7; //RC7
static volatile bit RC6 @ (unsigned)&PORTC*8+6; //RC6
static volatile bit RC5 @ (unsigned)&PORTC*8+5; //RC5
static volatile bit RC4 @ (unsigned)&PORTC*8+4; //RC4
static volatile bit RC3 @ (unsigned)&PORTC*8+3; //RC3
static volatile bit RC2 @ (unsigned)&PORTC*8+2; //RC2
static volatile bit RC1 @ (unsigned)&PORTC*8+1; //RC1
static volatile bit RC0 @ (unsigned)&PORTC*8+0; //RC0
/* PORTD bits */
#ifdef __PINS_40
static volatile bit RD7 @ (unsigned)&PORTD*8+7; //RD7
static volatile bit RD6 @ (unsigned)&PORTD*8+6; //RD6
static volatile bit RD5 @ (unsigned)&PORTD*8+5; //RD5
static volatile bit RD4 @ (unsigned)&PORTD*8+4; //RD4
static volatile bit RD3 @ (unsigned)&PORTD*8+3; //RD3
static volatile bit RD2 @ (unsigned)&PORTD*8+2; //RD2
static volatile bit RD1 @ (unsigned)&PORTD*8+1; //RD1
static volatile bit RD0 @ (unsigned)&PORTD*8+0; //RD0
/* PORTE bits */
static volatile bit RE2 @ (unsigned)&PORTE*8+2; //RE2
static volatile bit RE1 @ (unsigned)&PORTE*8+1; //RE1
static volatile bit RE0 @ (unsigned)&PORTE*8+0; //RE0
#endif
//* INTCON bits 中断控制寄存器 */
static volatile bit GIE @ (unsigned)&INTCON*8+7; //总中断使能位。0：屏蔽所有的中断请求；1：允许非屏蔽的中断。
static volatile bit PEIE @ (unsigned)&INTCON*8+6; //外部中断使能位。0：禁止；1：使能
static volatile bit T0IE @ (unsigned)&INTCON*8+5; //TMR0溢出中断使能位。0：禁止；1：使能
static volatile bit INTE @ (unsigned)&INTCON*8+4; //RB0/INT外部中断使能位。0：不使能；1：使能。
static volatile bit RBIE @ (unsigned)&INTCON*8+3; //RB端口变化中断时能位。0：不使能；1：使能。
static volatile bit T0IF @ (unsigned)&INTCON*8+2; //TMR0溢出中断标志位。0：无溢出；1：溢出。
static volatile bit INTF @ (unsigned)&INTCON*8+1; //RB0/INT外部中断标志位。0：RB0外部中断未发生；1：RB0外部中断发生。
static volatile bit RBIF @ (unsigned)&INTCON*8+0; //RB端口变化中断标志位。0：RB口无变化；1：RB口至少有一个引脚变化。
// alternate definitions
static volatile bit TMR0IE @ (unsigned)&INTCON*8+5; //
static volatile bit TMR0IF @ (unsigned)&INTCON*8+2; //
//* PIR1 bits中断标志寄存器PIR1 */
#ifdef __PINS_40
static volatile bit PSPIF @ (unsigned)&PIR1*8+7; //并行从端口读写中断标志位。0：没有读写操作发生；1：反之
#endif
static volatile bit ADIF @ (unsigned)&PIR1*8+6; //A/D转换器中断标志位。0：A/D转换没有完成；1：A/D转换完成。
static volatile bit RCIF @ (unsigned)&PIR1*8+5; //USART接收中断标志位。0：接收缓冲器空；1：反之。
static volatile bit TXIF @ (unsigned)&PIR1*8+4; //USART发送中断标志位。0：发生缓冲器满；1：反之。
static volatile bit SSPIF @ (unsigned)&PIR1*8+3; //同步串行端口（ssp）中断标志位。0：没有ssp中断条件发生；
static volatile bit CCP1IF @ (unsigned)&PIR1*8+2; //CCP1中断标志位。
static volatile bit TMR2IF @ (unsigned)&PIR1*8+1; //TMR2 TO PR2匹配中断标志位。0：没有匹配发生
static volatile bit TMR1IF @ (unsigned)&PIR1*8+0; //TMR1溢出中断标志位，0：无溢出
/* PIR2 bits */
static volatile bit CMIF @ (unsigned)&PIR2*8+6; //比较器中断标志位；0：比较器输入没有改变
static volatile bit EEIF @ (unsigned)&PIR2*8+4; //EEPROM写操作中断标志位。0：写操作没有完成或没有开始
static volatile bit BCLIF @ (unsigned)&PIR2*8+3; //总线冲突中断标志位。0：没有总线冲突发生
static volatile bit CCP2IF @ (unsigned)&PIR2*8+0; //CCP2中断标志位
//* T1CON bits TMR1控制寄存器 */
static volatile bit T1CKPS1 @ (unsigned)&T1CON*8+5; //TMR1输入时钟预分频选择位
static volatile bit T1CKPS0 @ (unsigned)&T1CON*8+4; //TMR1输入时钟预分频选择位
static volatile bit T1OSCEN @ (unsigned)&T1CON*8+3; //TMR1震荡器使能控制位。0：振荡器关闭
static volatile bit T1SYNC @ (unsigned)&T1CON*8+2; //TMR1外部时钟输入同步控制位。
static volatile bit TMR1CS @ (unsigned)&T1CON*8+1; //TMR1时钟源选择位。0：内部时钟的/4
static volatile bit TMR1ON @ (unsigned)&T1CON*8+0; //TMR1使能位。0：禁止
//* T2CON bits TMR2控制寄存器 */
static volatile bit TOUTPS3 @ (unsigned)&T2CON*8+6; //TMR2后分频选择位。
static volatile bit TOUTPS2 @ (unsigned)&T2CON*8+5; //TMR2后分频选择位
static volatile bit TOUTPS1 @ (unsigned)&T2CON*8+4; //TMR2后分频选择位
static volatile bit TOUTPS0 @ (unsigned)&T2CON*8+3; //TMR2后分频选择位。
static volatile bit TMR2ON @ (unsigned)&T2CON*8+2; //TMR2使能位。
static volatile bit T2CKPS1 @ (unsigned)&T2CON*8+1; //TMR2预分频选择位。
static volatile bit T2CKPS0 @ (unsigned)&T2CON*8+0; //TMR2预分频选择位