> UART_SendChar
>         bsf     STATUS,RP0              ; switch to bank 1

This only switches to either bank 1 or 3.  If you were previosly in banks 2
or 3 then this won't work.

>         btfss   TXSTA,1                 ; check TXMT flag and loop if

Use the mnemonics in the include file instead of hard coded bit numbers.  It
makes your code more readable, reduces that chance of getting the bit number
wrong, and saves everyone else time looking it up to make sure you did get
the bit number right.

>          goto   UART_SendChar           ; still not done sending the last
character

Why do you want to wait until the last character is sent to send the next
one?  Do you really need to make sure the previous character has gone out or
are you just trying to make sure the UART is ready to receive the next
character?  If so, you should be checking the TXIF bit in PIR1.

>         bcf     STATUS,RP0              ; switch back to bank 0

Or bank 2, depending on RP1.

>         movfw   UART_Tx                 ; put transmit value
>         movwf   TXREG                   ; in transfer register
>         return                          ; return from UART_SendChar

Overall, I really don't like calling this routine from the interrupt
handler.  First, it effectively reduces the available call stack size, at
least for any code that runs with interrupts enabled.  Second, this is such
simple logic that it would only take a few instructions to do in line.  I
would make a macro out of it if I wanted to use this code once in the
subroutine and once in the interrupt routine.  Third and most importantly,
doing a busy wait in an interrupt routine is usually a very bad thing.


********************************************************************
Olin Lathrop, embedded systems consultant in Littleton Massachusetts
(978) 742-9014, olin@embedinc.com, http://www.embedinc.com

--
http://www.piclist.com hint: To leave the PICList
mailto:piclist-unsubscribe-request@mitvma.mit.edu