Hello world not working (16F74)

[eng1]

What about checking the TRMT bit?

TXRDY:
    bsf STATUS,RP0          ; bank 1
Wait:
    btfss TXSTA, TRMT       ; transmission complete?
    goto Wait 
    bcf STATUS,RP0          ; bank 0
Send:
    movwf TXREG             ; send data 

    return

I would also provide a short delay after initialization of the USART module...

 

[ericgibbs]

Why two goto's?.

Change the BTFSC to BTFSS and delete the GOTO XMIT1

Here are the routines from my RS232 tutorial.

XMIT_RS232  	btfss   PIR1,	TXIF 	      ;xmit buffer empty?
     		GOTO	XMIT_RS232            ;no, wait
     		MOVWF   TXREG		      ;now send
                RETURN

Rcv_RS232   	BTFSS   PIR1,	RCIF 	      ; check for received data
     		GOTO    Rcv_RS232
                MOVF    RCREG,	W
                RETURN

hi,
Quite right, clumsy coding
Eric

 

[Gayan Soyza]

What about checking the TRMT bit?

TXRDY:
    bsf STATUS,RP0          ; bank 1
Wait:
    btfss TXSTA, TRMT       ; transmission complete?
    goto Wait 
    bcf STATUS,RP0          ; bank 0
Send:
    movwf TXREG             ; send data 

    return

I would also provide a short delay after initialization of the USART module...

Bente Petersen using the same technic

 

[imhereithink]

Finally got it working , i used the xmit subroutine from Nigel and it works perfectly. Thanks guys for all the help

 

[flemmard]

hi,
I use this subr on all my PIC prgms with no problems

;---- SERIAL UART ----
; Hardware Serial Communication Routines
TXRDY:
BTFSC PIR1,TXIF
GOTO XMIT1
GOTO TXRDY;busy,so loop
XMIT1:
MOVWF TXREG;send
RETURN

Are you sure that the receiving PC is OK?

Eric

Hi,
You hav any routine for PIC C to do serial communication?
Thanks

 

[Nigel Goodwin]

Hi,
You hav any routine for PIC C to do serial communication?
Thanks

I would expect any C compiler to have built-in routines for serial operations?.