Steren CAL-150 Instructivo De Uso página 165

There also exist errors during the use of programs, the LC
screen might display "Ne ERROR" or "Go ERROR"
Text and Graph Display
This calculator has a graph screen for the elaboration of
graphs, as well as the display of text for the elaboration of
formulas and commands. These two types of displays are
independent from each other.
In order to change between graph view and text view, press
the button.
Example: