CASIO fx-991ES - strange behavior from the past

[Csaba Tizedes]

Turn on your CASIO fx-991ES, press MODE then few times the right button and you can see how the contrast is increasing, then press left button and the contrast is became low. This is the same like on older graphical CASIOs, but maybe they forget to remove it from the firmware (because the contrast setting is another menu function (SHIFT+SETUP\DOWN\6))?

Csaba

[Dave Britten]

The fx-9860G (Slim and II models as well) can be adjusted with Shift+Left/Right, or from within the System menu. Likewise, the fx-5800P can be adjusted with Left and Right while the Mode menu is open, or from the dedicated contrast adjustment mode.

Presumably they give you two options because one is quicker and more convenient, and the other is more discoverable. If the contrast is adjusted to one of the extremes, you may not be able to read the screen to navigate to the dedicated contrast adjustment mode. And if it's not very discoverable, you'll end up with a lot of kids that have a dim screen due to low batteries - or dark screen due to fresh batteries - not realizing they just have to press Shift-Up/Down to adjust their TIs. (Definitely speaking from experience here.)