我參考了範例程式寫出來的主端和從端的程式..但是我在ICE2000裡一步一步慢慢執行時..就卡在I2C_BYTE_WRITE裡發出起始狀態候等待SSPIF為HI的迴圈...我參考了[PIC16F87X快速上手]一書中I2C章節各種模式設定..我看不出哪裡有錯誤
......................................................以下是我改的程式(如果不接受貼程式發問的話也希望建議一下可能是哪裡出錯了,我會去找板主介紹的書在試試)
(主控端)
LIST P=16F873A
#INCLUDE <P16F873A.INC>
I2C_Data equ 0x21
org 0x00
nop
goto Prog_Main
nop
nop
Prog_Main:
BANKSEL TRISB ; Select Bank 1
movlw b'11000000' ; setup PORTB
movwf TRISB
BSF OPTION_REG,NOT_RBPU ; Disable PORTB pull-ups
call InitI2C
Main:
BANKSEL I2C_Data ; Bank Switching, in case its bank is differ than I2C_Addr !!
movlw 0x99
movwf I2C_Data ; 設定欲寫入的資料
call I2C_BYTE_WRITE ; Write to I2C Device when Address & Data are set OK
call I2C_BYTE_READ
nop ; 將中斷點設定於此 , 應該看到 W 暫存器的值
nop ; 等於剛才寫入的資料
goto $
I2C_BYTE_WRITE: ; Write a Byte to I2C_Addr with I2C_Data
call StartI2C ; Set SSPCON2.SEN
call WaitI2C ; Wait PIR1,SSPIF
BANKSEL SSPBUF
movlw B'10001110' ; Write Command................
movwf SSPBUF
call WaitI2C
BANKSEL I2C_Data
movf I2C_Data,W
BANKSEL SSPBUF
movwf SSPBUF
call WaitI2C
call StopI2C ; Initial STOP Condition
call WaitI2C ; Wait Until STOP Condition Terminated
return
I2C_BYTE_READ: ; Read a Byte @ I2C_Addr to Buffer I2C_Data
call StartI2C ; Set SSPCON2.SEN
call WaitI2C ; Wait PIR1,SSPIF
BANKSEL SSPBUF
movlw B'10001111' ; Write Read Command..........
movwf SSPBUF
call WaitI2C
call RecI2C ; Enable I2C Receive
call WaitI2C ; Wait Until Buffer Received
BANKSEL SSPBUF
movf SSPBUF,W ; Save to I2C_Data First !!
BANKSEL I2C_Data
movwf I2C_Data
call NACKI2C ; Initial NACK Response !!
call WaitI2C ; Wait until NACK sent out
call StopI2C ; Initial STOP Condition
call WaitI2C ; Wait Until STOP Condition Terminated
return
InitI2C: ; The subroutine of I2C Initialization
BANKSEL TRISC
movlw B'00011000' ; Initial PortC,bit 3 & 4 as Input
movwf TRISC ; RC3 = SCL , RC4 = SDA
BANKSEL PORTC
movlw 0xff
movwf PORTC
movlw 0x09 ; This gives 100KHz I2C clock @ 4MHz......
banksel SSPADD
movwf SSPADD
movlw b'10000000' ; Disable slew rate control.
banksel SSPSTAT
movwf SSPSTAT
movlw b'00000000' ;
movwf SSPCON2 ; Setup MSSP for continuous reception.
movlw b'00101000' ; Enable MSSP and setup for I2C master
banksel SSPCON ; mode.
movwf SSPCON
return
StartI2C: ; Initiate the I2C START condition.
banksel SSPCON2
bsf SSPCON2,SEN
return

StopI2C: ; Initiate the I2C STOP condition.
banksel SSPCON2
MOVLW B'00000001'
MOVWF SSPCON2
return

RstartI2C: ; Initiate the I2C restart condition.
banksel SSPCON2
bsf SSPCON2,RSEN
return

NACKI2C:
banksel SSPCON2
bsf SSPCON2,ACKDT ; Set the ACK bit
bsf SSPCON2,ACKEN ; Initiate the NACK sequence.
return

ACKI2C:
banksel SSPCON2
bcf SSPCON2,ACKDT ; Clear the ACK bit
bsf SSPCON2,ACKEN ; Initiate the NACK sequence.
return

RecI2C:
banksel SSPCON2 ;
bsf SSPCON2,RCEN ; Set the receive enable bit.
return


WaitI2C: ; Poll for SSPIF
banksel PIR1
FLoop: btfss PIR1,SSPIF
goto FLoop
bcf PIR1,SSPIF
return
end
_________________________________________
(從屬端)
#INCLUDE <P16C62A.INC>
TEMP EQU 20H
ORG 0000H
GOTO START
ORG 0004H
BANKSEL SSPSTAT
BTFSC SSPSTAT,R
GOTO WAS_READ
WAS_WRITE:
BTFSC SSPSTAT,D
GOTO WRITE2
BANKSEL SSPBUF
MOVFW SSPBUF ;CLEAR BF
GOTO CLRIF
WRITE2:
BANKSEL SSPBUF
MOVFW SSPBUF ;CLEAR BF
MOVWF PORTB
MOVWF TEMP
BCF PIR1,SSPIF ;CLEAR SSPIF
GOTO END_INT
WAS_READ:
MOVLW B'10101010'
BANKSEL SSPBUF
MOVWF SSPBUF ;SET BF
BSF SSPCON,CKP ;RELEASE CLOCK LINE
CLRIF:
BCF PIR1,SSPIF ;CLEAR SSPIF
END_INT:
RETFIE
START:
BANKSEL TRISA
MOVLW B'11111111'
MOVWF TRISA
MOVWF TRISB
MOVWF TRISC
BANKSEL SSPCON
MOVLW B'00111110' ;I2C SLAVE, 7-BIT WITH INTERRUPT
MOVWF SSPCON
MOVLW B'00000000'
MOVWF PIR1
BANKSEL SSPADD
MOVLW B'10001110' ;I2C ADDRESS SETTING
MOVWF SSPADD
MOVLW B'11000000'
MOVWF INTCON
MOVLW B'00001000'
MOVWF PIE1
LOOP:
GOTO LOOP
END

前述兩個I2C的Slave程式都是用中斷方式處理，建議你還是要從I2C的規格先讀起，舫間有很多PIC16F877的書有I2C詳細的說明，推薦一本洪正瑞老師的＂詳細解析PIC16F877原理與應用＂第十四章有詳細的說明與範例。台科大圖書公司出版。

請問範例程式裡
[簡單的 Master 端 (Firmware) 及 Slave 端 (Hardware) 相對應的程式範例]
[Hardware SLAVE端程式範例 (AN734)]
[簡單Hardware SLAVE端程式範例]
這三個範例的SLAVE端程式到底有什麼不同
因為程式裡有一些我看不懂的設定..