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+--- Thread: Unstable 49G (/thread-5891.html)
Unstable 49G - Csaba Tizedes - 03-18-2016 10:19 PM
I've got a 49G and it seems to me, everything is OK. But if I press 6-8 keys (for example I start to key the digits od Pi) on the screen strange characters appears and the calculator is resets.
How can I connect it to PC without keypresses? It is possible to update the ROM to the latest stable version? Also without keypresses - because it will be reset again.
Thank you!
Csaba
RE: Unstable 49G - Tugdual - 03-19-2016 06:39 AM
I had something very similar on my old 48g. While I don't think the two machines share a lot in common, may be it can help you to know that the issue was a defective electrical contact on batteries. I used sand paper on metal plates that were corroded and the 48g is kicking again. I guess the 49g is using springs like the 50g but you might still want to investigate in that sense?
RE: Unstable 49G - Csaba Tizedes - 03-19-2016 10:27 AM
(03-19-2016 06:39 AM)Tugdual Wrote: I had something very similar on my old 48g. While I don't think the two machines share a lot in common, may be it can help you to know that the issue was a defective electrical contact on batteries. I used sand paper on metal plates that were corroded and the 48g is kicking again. I guess the 49g is using springs like the 50g but you might still want to investigate in that sense?
I cleaned all the contacts but nothing is happen.
Check my video about this problem: https://youtu.be/4CuhS8xxwLk
Csaba
RE: Unstable 49G - Csaba Tizedes - 03-19-2016 11:28 AM
(03-19-2016 10:27 AM)Csaba Tizedes Wrote: Check my video
"Warning: Invalid Card Data" at 01:53
Really strange patterns at 02:07~02:26
Any idea how can I fix it?!
Csaba
RE: Unstable 49G - Tugdual - 03-19-2016 12:53 PM
Definitely not the same issue I had. Looks like the RAM is fried.
Did you try to reset memory?
Could be a broken welding also. In that case you might want to randomly iron all the places where you see welding.
RE: Unstable 49G - Csaba Tizedes - 03-19-2016 01:06 PM
(03-19-2016 12:53 PM)Tugdual Wrote: Looks like the RAM is fried.
Did you try to reset memory?
Could be a broken welding also. In that case you might want to randomly iron all the places where you see welding.
First I want to update/downgrade(?) the ROM to the highest stable version, maybe that is will be help, but my problem is that, the calculator is continously fails, going to reset or simply not responses to keystrokes, therefore I cannot go to the Diagnostic mode and after that to the Terminal mode.
I want to try this: P0ERASE 1.0, but it is looks like impossible currently. I cannot to check the ROM version also...
Csaba
RE: Unstable 49G - Tugdual - 03-19-2016 02:50 PM
In my humble opinion, the ROM has nothing to see with the problem... More like hardware problem.
RE: Unstable 49G - Gerald H - 03-19-2016 02:54 PM
(03-19-2016 11:28 AM)Csaba Tizedes Wrote:(03-19-2016 10:27 AM)Csaba Tizedes Wrote: Check my video
"Warning: Invalid Card Data" at 01:53
Really strange patterns at 02:07~02:26
Any idea how can I fix it?!
Csaba
Try command PINIT.
RE: Unstable 49G - DavidM - 03-19-2016 04:35 PM
(03-19-2016 01:06 PM)Csaba Tizedes Wrote:(03-19-2016 12:53 PM)Tugdual Wrote: Looks like the RAM is fried.
Did you try to reset memory?
First I want to update/downgrade(?) the ROM to the highest stable version, maybe that is will be help, but my problem is that, the calculator is continously fails, going to reset or simply not responses to keystrokes, therefore I cannot go to the Diagnostic mode and after that to the Terminal mode.
On the very slim chance that the vestiges of a library in port memory is causing problems, you can also try a warm-start (ON-C) followed immediately by holding down the backspace key, which should disable the automatic library attachment process.
I agree with the others who are suggesting this looks more like a hardware issue, though.
I believe the 49g has a self-test in ROM, and you may want to attempt to run the various options to see what happens. The self-test is normally activated by pressing ON-D after the system is powered-up, presuming it's stable enough to do that. Your description of "I cannot go to the Diagnostic mode" makes me think this won't work, though.
RE: Unstable 49G - Tugdual - 03-19-2016 04:51 PM
Did anything special happen? Like a fall, stayed for long in sun, lightning strike, visited a nuclear plant, cooked in micro wave?
RE: Unstable 49G - Csaba Tizedes - 04-04-2016 09:01 AM
Finally I gave up the trying, I met my friend this weekend from University and he gave me his unused 49G. So, I have a fully workable 49G with 1.05 system. Is this safe to upgrade to 1.18 or not?!
Csaba
RE: Unstable 49G - Tugdual - 04-04-2016 09:22 AM
(04-04-2016 09:01 AM)Csaba Tizedes Wrote: Finally I gave up the trying, I met my friend this weekend from University and he gave me his unused 49G. So, I have a fully workable 49G with 1.05 system. Is this safe to upgrade to 1.18 or not?!Golden rule: if it is operating well... don't touch it
Csaba
