Chybí ti nastavení oscilátoru. Pro krystal nad 4Mhz _HS_OSC, pod 4Mhz _XT_OSC, viz strana 121 datasheetu.
list p=16F877A, R=DEC
include “p16f877a.inc”
__config _BODEN_OFF & _CP_OFF & _PWRTE_ON & _WDT_OFF & _HS_OSC & _DEBUG_OFF & _CPD_OFF & _LVP_OFF
org 0x00
Start
BSF STATUS,RP0
BCF TRISD,0
BCF STATUS,RP0
BSF PORTD,0
GOTO $ ;wait here
end