Get rid of the old debugon command and upgrade to the link on the tool bar at the top. Don't click run. Click debug. The debug screen will appear and it will not run until you click the "run" button. When you launch from the debug link it will allow for the user to stop the loop and every thing else. Be careful. With the speed at which esp basic is running now the debugger might cause an epileptic seizure.
t = 0
[poo]
if t = 0 then
t = 1
else
t = 0
end if
goto [poo]
http://esp8266basic.com
A BASIC interpreter for your ESP
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