Does anyone know if it is possible to make a Block or a layer flash on an AutoCad drawing in order to draw attention to it on plan?

Yes it's possible.
 
 
.
.
.
but controlling when & why it flashes may not be so easy to implement.
Would probably be done with programming, so not possible in LT version.

There are also other ways for drawing attention to drawing objects - selection highlighting, changing color temporarily, lineweights, etc.

I am using Cad 2009 full version. I want to be able to have the columns in a building drawing flash on command. Highlighting has not been quite what I am looking for.
 
ANy further help would be appreciated!
 
Thanks

Here's a Q&D lisp routine to flash objects on a layer.The layer(s) to flash could be entered by user, or hard-coded. See what you think. Type "flash" to run it.[code](defun c:flash ()  (setvar "cmdecho" 0)  (setq Ename (car (entsel "\nSelect obj to flash layer: ")))  (setq Lay (cdr (assoc 8 (entget Ename))))  (setq LaySet (ssget "_X" (list (cons 8 lay))))  (while t     (sset_hl laySet 3)
     (redraw)     (command "._delay" "100")     (sset_hl laySet 4)
     (redraw)
     (command "._delay" "100")  )  (setvar "cmdecho" 0)  (princ))(defun sset_hl (sset_1 val)  (setq s_length (sslength sset_1))  (setq count 0)  (repeat s_length     (setq en (ssname sset_1 count))     (redraw en val)     (setq count (1+ count))  ))[/code]CarlB2009-11-06 02:36:53