HP 39gs_40gs_Mastering The Graphing Calculator_English_E_F2224-90010

Hard reboot (with loss of memory)
To completely reset the calculator’s memory back to factory settings press
ON+SK1+SK6. (SK1=”screen key
1”) When doing this, don’t press them all at once; hold down the
ON key and, while still holding it down,
press the first and then the last screen keys. Release them in the opposite order. Don't release
SK1 and SK6
together - release
SK6, then SK1, then ON. This is deliberately made complex so that it won’t happen by
accident!
This type of reset will always cause complete loss of data. If you find that the screen fills with garbage, or if
the calculator’s in-built diagnostic routine starts to run, then it is just that you have not released them in the
right order. Simply try again.
Calculator Tip
1.
2.
from the web.
lator afterwards.
3. ON+SK4
test the calculator’s components.
.
If your calculator is really thoroughly locked up or won’t turn on
then try the procedures listed below this tip.
My past experience with these calculators is that they do tend to
lock up occasionally, particularly if you load aplets and programs
I usually suggest to my students that they regularly
save their work to a PC and perform a hard reboot about once a
month, reloading the saved work onto the calcu
Pressing by mistake will
result in the screen shown right.
This is a special diagnostic mode
that can be used by engineers to
There is nothing wrong with
experimenting with it but it is of no use to the average user. To exit,
simply reboot normally by pressing
ON+SK3
Locked Calculator? Won't turn on? Turns on briefly and then immediately off?
Try the following:
• Try a soft reboot using ON+SK3.
• Try a paperclip in the hole in the back (gently).
•
Try
Is it possible that the screen is blank because the contrast is turned to extremely light?
ON and to make the screen darker. (Hold down ON and press repeatedly.)
Use
ON and to lighten the screen.
• Change the batteries for new ones. Try this more than once because sometimes batteries are dead
right off the shelf if they've been in the shop too long. Try replacing the backup battery too. Make
SURE you’ve put the batteries in right way around. Putting them in reversed may seriously damage
the calculator.
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