memclear
graphics 300,300
timer 1000, [doit]
[top]
x = 0
gcls
text 10,100,"Anolog in",180 + 90
text 100, 250, "Time (1 second)",0
wait

[doit]
aOLD = a
a = io(ai) / 4
xOLD = x
x = x + 10
line xOLD,aOLD,x,a,5
if x > 300 then goto [top]
wait

This is a simple analog input graph.
It checks the analog input pin on the esp8266 every second and displays the result as a graph.

Notice how when the graph reaches the right hand side it clears the graph area and starts again from the left.