Ricoh Touch Screen Calibration lost

[Guest]

Since replacing the main CPU board the Ricoh MPW2400 copier works fine, but loses its touch screen calibration.
It calibrates fine once set, but days later on restart one is back to its incorrect setting.
I see mention elsewhere that this is a function of a bad touch panel, but that makes no sense.
I have written code myself for this functionality....
The cpu calibration routine must save the couple x,y locations, then it does some math to sort out the correct geometry to match what is required.
The data must be saved to NVRAM or somewhere when the power is off to be retained.
Seems to me it isn't doing this as it should.
Either that, or the touch panel despite calibrating, offers x,y positions that are outside the original programmer's self enforced limits, and is discarding them, not saved, despite allowing the touch panel to work exactly correctly.
I swapped the NVRAM battery on CPU board swapping, it should be fine but I haven't gone back and checked it.
Any thoughts on this from those having experienced this?
Thanks much.

[Max]

Re: Ricoh Touch Screen Calibration lost

Replace the screen and you will probably find it will fix it. Pretty sure its not a software issue with x and y, just a faulty screen.

[Tonerbomb]

Re: Ricoh Touch Screen Calibration lost

A few years back, Ricoh had a rash of bad touch panels which for a while were warranty replacements. you probably have one of those original panels. The warranty program ended a couple years ago, so you will need to buy a new one.................

[cornwallav8r]

Re: Ricoh Touch Screen Calibration lost

Thanks for the info. I am guessing we are both correct.
The bad panel calibrates correctly, but the corrected values are thrown out as too far out of spec by the coded firmware and are rejected.
Will replace the panel.

[sandmanmac]

Re: Ricoh Touch Screen Calibration lost

Thanks for the info. I am guessing we are both correct.
The bad panel calibrates correctly, but the corrected values are thrown out as too far out of spec by the coded firmware and are rejected.
Will replace the panel.

Really?
My guess is that the material that connects the ribbon cable to the panel is defective - because that's what it always is with these panels

[cornwallav8r]

Re: Ricoh Touch Screen Calibration lost

Really?
My guess is that the material that connects the ribbon cable to the panel is defective - because that's what it always is with these panels

Yes really....the touch screen works perfectly for days on end after calibration until it is shut off.
It isn't intermittent at all.....so far as my experience shows here. Though I am sure you other techs have more experience.
I ordered a new one off Ebay after spending 30 minutes with Ricoh on the phone, getting passed around to 6 different people, and finally told "you are time and material, we won't sell you parts, but will be happy to send out a tech and charge you".....


I never said it was a software issue, only that the firmware was throwing out the bad calibration data, not storing it...because it calibrates fine temporarily, until the unit is shut down.