i have implement an usart routine with PIC16F877 to display a simple menu
message.
it's seems to work well but i'm not able to stabilyse my menu.
each time i power on my circuit menu is displayed and this process continue
all 2 seconde (about).
i want that menu come just one time and wait for another task.
if someone can help me how to do that i will appreciate.
a part of my routine is :

 list      p=16f877            ; list directive to define processor
 #include <p16f877.inc>        ; processor specific variable definitions

 __CONFIG _CP_OFF & _WDT_ON & _BODEN_ON & _PWRTE_ON & _XT_OSC &
_WRT_ENABLE_ON & _LVP_ON & _DEBUG_OFF & _CPD_OFF

temp0  equ 20h
check  equ 21h

CR equ 0x0D
LF equ 0x0A

 ORG 00h ; Reset Vector
main: goto init_uart

ORG 10h ; Begining of Program space

;---------------------------------------------------------------------------
--
; Main Program
;---------------------------------------------------------------------------
--

init_uart:
 bsf STATUS,RP0 ; select bank 1
 bcf STATUS,RP1
 movlw 19h   ;9600 baud @4MHz
 movwf SPBRG
 movlw b'00100100'  ;transmit enable, Async, High baud rate
 movwf TXSTA
; bsf PIE1,TXIE
bsf PIE1,RCIE
 bcf STATUS,RP0 ; selact bank 0
 bcf STATUS,RP1
 movlw b'10010000'  ;Serial port Enable, continous reception
 movwf RCSTA
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Start:

 clrf temp0  ;initialize table index
main_loop:
 movf temp0,w  ; update table index
 call menu  ; get menu table entry
 movwf check
 movf check,w  ;load acc with table char
 bz continue1
 call put_char ;display character
 incf temp0,f  ;inc. index
 goto main_loop ;repeat until done

continue1:

 goto    continue1
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put_char:
; btfss PIR1,TXIF ;check TX Buff flag
 bsf STATUS,RP0 ; select bank 1
 bcf STATUS,RP1
 btfss TXSTA,TRMT
 goto put_char ;If buff full wait
 bcf STATUS,RP0 ; select bank 0
 bcf STATUS,RP1
 movwf TXREG  ;if buff empty output next char
 return
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echo_char:
 bcf STATUS,RP0 ; select bank 0
 bcf STATUS,RP1
 btfss PIR1,RCIF
 goto echo_char ;If buff full wait
 movf RCREG,w
 call put_char ;if buff empty output next char
 return
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menu:
 addwf PCL,f
 dt "MENU:",CR,LF
 dt "READ TEMPERATURE...... [1] ",CR,LF
 dt "SET U/C ATTENUATION....[2] ",CR,LF
 dt "SET D/C ATTENUATION....[3] ",CR,LF,0
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 end