Casio fx-991EX vs Hp 50g speed difference

[ijabbott]

(07-14-2018 10:27 AM)pier4r Wrote:  another result that may be interesting.

http://www.hpmuseum.org/forum/thread-9750.html (sum, trig, power/root , exp/log)

I appear to have one of the "fast" batch. The diagnostics show "CY-235 VerB".

To enter diagnostics mode, while holding "SHIFT" and "7" together, press "ON", then release all buttons. You should see:

Quote:DIAGNOSTIC

Press AC

(If it doesn't work, press and release "ON" first, then try again.)

Pressing "9" in diagnostic mode shows:

Quote:8888888888888888

8.888888889x10^15

Then pressing "SHIFT" repeatedly goes through some display tests, ending with:

Quote:CY-235 VerB

Press AC

(The version may be different on the "slow" batch.)

Pressing "AC" shows "00" in the top corner of the display. If you press the keys in the correct order, it increments to "01", "02" etc.

On the initial diagnostic screen, pressing "8" goes into a more brief keyboard test where various labels get highlighted when you press the corresponding key (although the \(x\) key is labelled as "[logab]" for some reason!). After pressing all the keys, the display changes to:

Quote:Solar MODEL OK!