Ok,thank you for your reply. It is clear for me now. There is a shortcut
from SIM ,My question at this point is should I use Ctrl+F10 or F10 as you
said because  on V 3.99 "Project|Build all" correspond to "Ctrl+F10" and not
F10,in my  MPLAB version "F10 = Make Project"  and  "Ctrl+F10 =Project|build
all". Thank you again for your help.

Ed.

At 08:59 AM 10/23/98 +0200, you wrote:
>You can edit from the SIM (I start editing my new projects in SIM mode).
>
>Just make you changes in the program window (in SIM mode), hit F10 (or
>Project|Build All) and carry on SIMming. No need to go back to editor mode
>first.
>
>Quentin
>
>