The Main Memory Backup battery in my Sharp Wizard OZ-7620 is depleted. I have replaced the 2 replaceable batteries but I don't know how to restore the system.

contact SHARP?
google SHARP wiizard oz-892 support.

Hi,
You need to Contact the manufacturer.Go to authorized service centre of sharp .They will provide you the code to bypass the lock.
Thank you

It calculator tells you Ram Cleared each time you turn it on, the most likely reason is that the backup battery is depleted. Its role is to keep the memory modules electrically refreshed when calculator is turned off. If the backup battery is dead, the memory is erased when you turn calculator OFF. Main batteries no longer supply power and the contents of the memory are cleared.

1. Check that main batteries are good and inserted in calculator.
2. Turn calculator OFF.
   
3. Replace the backup battery.
4. Turn calculator ON.
5. Press the [CLEAR] key to erase the "Ram Cleared" message.
   

Hello,
To answer the question you asked. No the backup battery does not affect the main batteries. It is there to keep the memory electrically refreshed when calculator is turned off. You will know that the backup is depleted or almost depleted if the screen displays RAM CLEARED, everytime you turn the calculator ON.

Now to the calculator not turning ON. IF THERE ARE NO HARWARE PROBLEMs with your calculator (of this I cannot judge for I am no prophet) , it may be that the screen is too light and you cannot see what it displays. If that is the case, you can darken it as follows.
1. Press [2nd] key and release it.
2. Press [ArrowUp] key and release it.
3. Repeat Steps 1 and 2 in sequence, until screen darkins enough. You may have to repeat the sequence several times.

Hope it helps.

Friend, try to replace the battery. If it doesn't work try to press firmly the LCD connection interface underneath the screen because such unit has lossen connection.use T6 screwdriver to open the unit then slowly firmly press the LCD connector on the interface. Such thing will solve the problem. good luck

unscrew 3 little screws at the bottom cover using jewelry phillip driver-remove the cover- you will see further instructions inside the cover. This model requires 5 batteries CR2032 (4 for main memory-1 for backup memory)-Hope it helps.

On the back of the unit, there is a battery selector switch. Move the selector to the 'replace batteries' position. Now you can open the main battery compartment. Adjacent to the main compartment is a smaller hatch secured by a small hex-head screw. Loosen and remove the screw to remove the hatch cover. Then you can remove and replace the old 2032 battery with a new one. Reverse the procedure to secure the hatch, ensure you have fresh batteries in the main battery compartment, replace the main hatch, select 'normal operation' and you should be good to go.

Charles Klaus

103 Club Colony Circle

Blythewood,SC 29016

803-736-4382

www.thewizardshop.net

email: [email protected]

Do an ALL RESET. The only way i know of to do it is to hold the ON and Reset at the same time. Then select yes at the promt. Then wait 2 mins and take out batteries. Reinsert and turn on. it will re-format. This is the only way i know of how to ressurect it, but it deletes ALL you data.
Thanks

-are all pda's this way? All PocketPCs are this way. I don't own a P**m so I can't speak to them. -When the main battery depletes to the point where the unit shuts off how long do you have before data is lost? Until the backup battery dies. -Is the backup battery just used when changing main batteries or does it take over when the main battery goes dead? If so how long do you have before it is dead? I've never had it happen, so I cannot say how long, but if you continue to try to use the PDA on the backup battery it won't be long (minutes) if it even lets you do that. The backup is there to bridge over battery changes and to act as a safety net if you run the main batteries totally flat. -does the backup battery recharge or does it have to be replaced? Replace. -with a fully charged unit how long can it be left off before data is lost? Depends on the machine. Most of us leave the thing in the charger overnight every night, so this issue doesn't come up. You could try an experiment for 1, 2, 3 days, looking each day at the battery remaining and work up an estimate. I would expect maybe a week or more. Remember, even "off" the machine is still drawing power to maintain the RAM memory.