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HP Forum Archive 14

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HP 49 G Key board problem
Message #1 Posted by Rennel on 24 Feb 2004, 11:19 p.m.

My fourth row (from the bottom) including the keys ALPHA, 7, 8, 9, and multiplication doesn't work. is there any way i can fix it?

      
Are the keys hard to press?
Message #2 Posted by Eddie Shore on 24 Feb 2004, 11:54 p.m.,
in response to message #1 by Rennel

I heard the wiggle fix is good, but never had to try it myself.

            
"Wiggle fix" is for 49g+
Message #3 Posted by Jeff on 25 Feb 2004, 7:14 a.m.,
in response to message #2 by Eddie Shore

The "wiggle fix" is used on the 49g+ keyboard for individual keys that do not work. This sounds like a different kind of problem, either bad connection between keyboard and pcb or broken traces, etc.

                  
Re: "Wiggle fix" is for 49g+
Message #4 Posted by Eddie Shore on 25 Feb 2004, 3:53 p.m.,
in response to message #3 by Jeff

Thanks Jeff.

I'm starting to get tired of the 4 key not working properly on my 49G+, so I'm trying the wiggle fix. Unless HP may be getting a call from me. (not to mention the rubber border started to fall off...)

                        
Re: "Wiggle fix" is for 49g+
Message #5 Posted by Rennel on 25 Feb 2004, 10:23 p.m.,
in response to message #4 by Eddie Shore

Hey what is this wiggle fix? I figured out that if i press my screen the keys in the row that doesn't work seem to work, but only when i press my screen. Any suggestions?

Thanks

                              
Re: "Wiggle fix" is for 49g+
Message #6 Posted by Eddie Shore on 26 Feb 2004, 12:39 a.m.,
in response to message #5 by Rennel

I'm trying it too: I think it is just wiggling the key really fast (with the calc off of course). We'll see how it works.

                              
Re: "Wiggle fix" is for 49g+
Message #7 Posted by Jeff on 26 Feb 2004, 7:49 a.m.,
in response to message #5 by Rennel

The "wiggle fix" is used on the 49g+ to attempt to get intermittent keys on the early production-run units to work. It involves pressing the offending key down firmly, then "wiggling" from side to side 10 or more times. It did not work for me, and even if it did, it sounds like it could possibly produce long term damage. There is no reason users of a new product should have to resort to such a procedure (IMHO).
If you indeed have a 49g as opposed to a 49g+, then the "wiggle fix" does not apply to you. Your problem sounds like a problem discussed in earlier threads, involving the connection between the keyboard and cpu board.

                        
Re: "Wiggle fix" is for 49g+
Message #8 Posted by Jeff on 26 Feb 2004, 7:41 a.m.,
in response to message #4 by Eddie Shore

Eddie,
You should definitely call hp. There is no reason you should have to keep a calculator with a key that does not work. There are various reports that if you call, they will either request your unit back first and then send a new one, or send you a new one and ask for your old one back after, or not bother asking for your old unit back at all. Whichever, you should end up with a new one.

                              
It's going back tomorrow, Jeff.
Message #9 Posted by Eddie Shore on 27 Feb 2004, 1:06 a.m.,
in response to message #8 by Jeff

I called HP and I'm sending it for a replacement (it will only be a week... I'll use my HP backups for now). Thanks, Jeff.

            
Re: Are the keys hard to press?
Message #10 Posted by Rennel on 25 Feb 2004, 3:37 p.m.,
in response to message #2 by Eddie Shore

No the keys are normal. Nothing happens when i press them. By the way what it the wiggle fix?

                  
Keys still don't register in the latest version of HP-49G+
Message #11 Posted by Pocketcom Mania on 25 Feb 2004, 10:32 p.m.,
in response to message #10 by Rennel

My HP-49G+ was manufactured in February 2004 with a serial no. CN402XXXXXXXXXX. After I pressed a digit key 10 times very quickly, not all 10 digits turned up! I did the same test on my HP-48SX and HP-15C but they passed it.

                        
Re: Keys still don't register in the latest version of HP-49G+
Message #12 Posted by Gene on 25 Feb 2004, 10:41 p.m.,
in response to message #11 by Pocketcom Mania

That's not necessarily a sign of a similar problem some people reported earlier.

These things can be affected by "keytime" settings, for example.

Generally, if you have a keyboard problem, you know it without having to resort to much of a test.

If you still think you're having a problem, I would suggest calling HP at 1-800-HPINVENT and discuss it with them again.

                              
Re: Keys still don't register in the latest version of HP-49G+
Message #13 Posted by S. Martin on 26 Feb 2004, 9:33 a.m.,
in response to message #12 by Gene

Correct me if I'm wrong:

In ROM 1.23 a KEYTIME-> returns 0.0, indicating this command really isn't a factor in key registering issues.

                                    
Re: Keys still don't register in the latest version of HP-49G+
Message #14 Posted by Veli-Pekka Nousiainen on 26 Feb 2004, 8:58 p.m.,
in response to message #13 by S. Martin

"Correct me if I'm wrong:

In ROM 1.23 a KEYTIME-> returns 0.0, indicating this command really isn't a factor in key registering issues."

Try 2000 ->KEYTIME and see it yourself!
[VPN]

                                          
Re: Keys still don't register in the latest version of HP-49G+
Message #15 Posted by Pocketcom Mania on 28 Feb 2004, 12:48 p.m.,
in response to message #14 by Veli-Pekka Nousiainen

It seems that after plugging in this value, the same problem still happened again......

                                                
Re: Keys still don't register in the latest version of HP-49G+
Message #16 Posted by James M. Prange on 28 Feb 2004, 6:56 p.m.,
in response to message #15 by Pocketcom Mania

Doing 2000 \->KEYTIME means that if the same key is pressed again in less than 2000 ticks (1 tick = 1/8192 second), it won't register. This is intended as a debouncing method. The 49G's default of 1365 seems a bit high for many users. The 49g+ uses a default of 0, which suggests to me that the developers didn't expect that this method of debouncing was needed. I'd suggest using a non-zero keytime "just in case", but make it small enough that it won't reject intentional consecutive presses of the same key. I use a value of 512 (1/16 second), as I'm sure that I can't intentionally press the same key twice in that interval, but I suppose that the "best value" depends on the user.

Edited: 28 Feb 2004, 8:31 p.m.


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