1：MPALB X IDE用戶指南里面例子的配置位寫法：

2：根據MPALB X IDE用戶指南里面的描述，可以自動生成配置位的代碼

3：根據MPALB X IDE用戶指南，說明配置位的編寫是和編譯器相關的，因此我們看編譯器的說明文檔

4：根據X8編譯器的說明文檔，看編譯器安裝目錄下的文檔說明

5：下面就是編譯器安裝目錄下的文檔說明

16F877A Support Information

#pragma config Usage

#pragma config =

For example:
// Brown-out Reset Enable bit: BOR disabled
// Data EEPROM Memory Code Protection bit: Data EEPROM code protection off
// In-Circuit Debugger Mode bit: In-Circuit Debugger disabled, RB6 and RB7 are general purpose I/O pins
// Flash Program Memory Write Enable bits: Write protection off; all program memory may be written to by EECON control
// Oscillator Selection bits: XT oscillator
// Watchdog Timer Enable bit: WDT disabled
// Flash Program Memory Code Protection bit: Code protection off
// Low-Voltage (Single-Supply) In-Circuit Serial Programming Enable bit: RB3 is digital I/O, HV on MCLR must be used for programming
// Power-up Timer Enable bit: PWRT disabled
#pragma config BOREN = OFF, CPD = OFF, DEBUG = OFF, WRT = OFF, FOSC = XT, WDTE = OFF, CP = OFF, LVP = OFF, PWRTE = OFF

#pragma config =

For example:
// Brown-out Reset Enable bit: BOR disabled
// Data EEPROM Memory Code Protection bit: Data EEPROM code protection off
// In-Circuit Debugger Mode bit: In-Circuit Debugger disabled, RB6 and RB7 are general purpose I/O pins
// Flash Program Memory Write Enable bits: Write protection off; all program memory may be written to by EECON control
// Oscillator Selection bits: XT oscillator
// Watchdog Timer Enable bit: WDT disabled
// Flash Program Memory Code Protection bit: Code protection off
// Low-Voltage (Single-Supply) In-Circuit Serial Programming Enable bit: RB3 is digital I/O, HV on MCLR must be used for programming
// Power-up Timer Enable bit: PWRT disabled
#pragma config BOREN = 0x0, CPD = 0x1, DEBUG = 0x1, WRT = 0x3, FOSC = 0x1, WDTE = 0x0, CP = 0x1, LVP = 0x0, PWRTE = 0x1

#pragma config =

For example:
// Brown-out Reset Enable bit: BOR disabled
// Data EEPROM Memory Code Protection bit: Data EEPROM code protection off
// In-Circuit Debugger Mode bit: In-Circuit Debugger disabled, RB6 and RB7 are general purpose I/O pins
// Flash Program Memory Write Enable bits: Write protection off; all program memory may be written to by EECON control
// Oscillator Selection bits: XT oscillator
// Watchdog Timer Enable bit: WDT disabled
// Flash Program Memory Code Protection bit: Code protection off
// Low-Voltage (Single-Supply) In-Circuit Serial Programming Enable bit: RB3 is digital I/O, HV on MCLR must be used for programming
// Power-up Timer Enable bit: PWRT disabled
#pragma config CONFIG = 0xFF39

For example:
// IDLOC @ 0x2000
#pragma config IDLOC0 = 0x3FFF

#pragma config Settings

Register: CONFIG @ 0x2007

BOREN =	Brown-out Reset Enable bit
OFF	BOR disabled
ON	BOR enabled

CPD =	Data EEPROM Memory Code Protection bit
OFF	Data EEPROM code protection off
ON	Data EEPROM code-protected

DEBUG =	In-Circuit Debugger Mode bit
OFF	In-Circuit Debugger disabled, RB6 and RB7 are general purpose I/O pins
ON	In-Circuit Debugger enabled, RB6 and RB7 are dedicated to the debugger

WRT =	Flash Program Memory Write Enable bits
OFF	Write protection off; all program memory may be written to by EECON control
HALF	0000h to 0FFFh write-protected; 1000h to 1FFFh may be written to by EECON control
1FOURTH	0000h to 07FFh write-protected; 0800h to 1FFFh may be written to by EECON control
256	0000h to 00FFh write-protected; 0100h to 1FFFh may be written to by EECON control

FOSC =	Oscillator Selection bits
XT	XT oscillator
LP	LP oscillator
EXTRC	RC oscillator
HS	HS oscillator

WDTE =	Watchdog Timer Enable bit
OFF	WDT disabled
ON	WDT enabled

CP =	Flash Program Memory Code Protection bit
OFF	Code protection off
ON	All program memory code-protected

LVP =	Low-Voltage (Single-Supply) In-Circuit Serial Programming Enable bit
OFF	RB3 is digital I/O, HV on MCLR must be used for programming
ON	RB3/PGM pin has PGM function; low-voltage programming enabled

PWRTE =	Power-up Timer Enable bit
OFF	PWRT disabled
ON	PWRT enabled

Register: IDLOC0 @ 0x2000

Register: IDLOC1 @ 0x2001

Register: IDLOC2 @ 0x2002

Register: IDLOC3 @ 0x2003

配置位的大概說明：

總結：我們可以根據編譯器的文檔說明來自己編寫配置位，也可以使用IDE來自動生成。推薦使用自動生成的配置位代碼。