RTC (PCF8583) with 16f877 PIC Problem

[kvrajasekar]

RTC problem...

Hi all,

I am using RTC (PCF8583) with 16f877.I am not familiar with I2C interfacing.I used the following codes,while readiing data sheets and refering some sites.But i controller gets hanging problem when i used the coding.

Please help me to solve the problem....

Initialised RC3(SCL) and RC4(SDA) as input.

Configure the MSSP as an I2C master controller
movlw b'00101000' ; Select I2C master mode

movwf SSPCON
movlw I2CRATE ; Set the bus speed

movwf SSPADD
movlw b'00000000' ; And clear any status flags

movwf SSPSTAT
call I2CStop ; Ensure the bus is free

; Generates an I2C start condition.
I2CStart:

bsf SSPCON2,SEN ; Generate START condition
btfsc SSPCON2,SEN ; And wait for it to complete
goto $-1
return
; Generates an I2C restart condition.
I2CRestart:

bsf SSPCON2,RSEN ; Generate RESTART condition
btfsc SSPCON2,RSEN ; And wait for it to complete
goto $-1
return
; Generates an I2C stop condition.

I2CStop:

bsf SSPCON2,PEN ; Generate STOP condition
btfsc SSPCON2,PEN ; And wait for it to complete
goto $-1
return
; Transmits the byte in W to the I2C bus.

I2CWrite:
movwf SSPBUF ; Initiate I2C write

btfsc SSPSTAT,R_W ; And wait for completion
goto $-1
return
; Recieves a byte from the I2C and returns its value.
I2CRead:

bsf SSPCON2,RCEN ; Initiate I2C read
btfsc SSPCON2,RCEN ; And wait for completion
goto $-1

movf SSPBUF,W ; Then read the data value
return
; Sends an I2C ACK signal to the slave device.
I2CAck:

bcf SSPCON2,ACKDT ; Send acknowledgement
bsf SSPCON2,ACKEN
goto I2CWait
; Sends an I2C NAK signal to the slave device.
I2CNak:

bsf SSPCON2,ACKDT ; Send negative acknowledgement
bsf SSPCON2,ACKEN
; Waits for the current I2C action to complete.