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View Full Version : How you erase a character in a Tv terminal



HED GROUP
03-20-2009, 08:27 AM
{{
Hi I send to the forum this problem so please can somebody explain me
why we can't erase a character on screen, Use the provided tv terminal
object so with an x and y values you can position the cursor.
}}
CON
·_clkmode = xtal1+pll16x
·_xinfreq = 5_000_000

OBJ
· term········· : "tv_terminal"
·
PUB Init
·term.start(12)················ ''Initialize TV
·term.out($00)················· ''Clear screen
·term.str(string("PARALLAX"))·· ''Print PARALLAX to tv terminal
·term.gotoxy(0, 0)············· ''Position cursor to x=0 and y=0
' term.str(string(" "))········· ''Try placing a " " do not erase the P
' term.out($20)················ ''Try placing a hex 20 (space) do not erase the P
' term.out($65)················ ''Try placing a A to remplace the P do not erase the P
'How you erase one character

Mike Green
03-20-2009, 09:03 AM
The object "tv_terminal" is not a text-based display driver. It's a graphics driver that happens to have the ability to draw characters as graphics. The "tv_terminal" object is more of a demonstration program than a useful text driver. It's possible to add special code to test for a space character and call the graphics routines to erase the next character cell on the display, but it may be easier to just use a text display driver like TV_TEXT. There's also a nice windowed text driver in the Object Exchange. In any event, you can't erase one character with "tv_terminal".