I've checked the hardware many times, but I checked again and I'm definately 
on pin 17 (it's the 28 pin package).  When I clear the tris bit for the TX 
pin before enabling the UART, the pin is driven low for a few instruction 
cycles before it goes high and stays high.

My polling loop right now is:
forever loop
  delay_100ms( 5 )
  LED = high
  delay_100ms( 1 )
  if (TXIF == low) then
   LED = low
  else
   TXREG = "H"
  end if
  delay_100ms( 5 )
  LED = low
end loop

So I'm using the LED to help me see what TXIF is.  TXIF never goes high, so 
I never even try to transfer a byte, so with this code, it's no surprise 
that I'm getting no signal on TX.

Jason



----- Original Message ----- 
From: "trossin" <ted_rossin@yahoo.com>
To: <piclist@mit.edu>
Sent: Tuesday, October 17, 2006 3:57 PM
Subject: Re: [PIC] USART on 16F876


>
> Enabling interrupts will not be the answer.  I just left this in comments 
> in
> case I want to enable it one day.  I have used this code on many projects
> (previously in assember form) without trouble on many 16F87x parts.  When
> you enable the UART it will override the PORTC TX and RX I/O control so in
> theory it does not matter what you set the TRISC value to.  When TXEN (bit 
> 5
> of TXSTA) is set, PORTC[6] will become an output.
>
> In looking at your code again it seems that you have the correct settings.
> The only thing I can suggest is to create a loop that checks the status 
> like
> my RS232putch and keep sending a character with lots of toggles.  Also,
> double check that you are using the correct pin (pin 25 on the 40-pin
> package, pin 17 on the 28 pin package).  Sometimes it is the simple stuff
> that is going wrong when nothing makes sense.


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