Omron NT600M does not start properly

Hi all!
I got an Omron NT600M-DT122 to fix.
I starts up now somehow, but I do not get any text on screen. AFAIK I should get _something_ when the battery has been disconnected, some
kind of optional menu.
The first problem was by some reason a resistor between reset (7705 output) and +5V, then I got some life to the data and address lines. Next, I wanted it stable, and I have to fix the EPROM socket.
When that was done, it starts up "properly", the Run led is on when resseting, the battery flashes for a short while, backlight comes on, then nothing more happens.
Any ideas anyone?
BR Sonnich
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jodleren wrote:

I should add, that there were no signales on data and address lines before this, and that the backlight did not come on. Though, for some odd reason, the backligh came on after some 20 seconds. But the data lines were still dead.
> When that was done, it starts up "properly", the Run led is on when

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I should mention here, that it is a PLC Display panel.
Sonnich
jodleren wrote:

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It may be worth checking the contrast pot underneath the rubber protective flap (front of screen, bottom right IIRC), and adjusting as necessary.
Rob
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Robbie Mayhem wrote:

Yep, found it, but it does not do much difference.
While looking at the EPROM it looks it is looping in something like address $02xx... it is probably waiting for something.... so something else can be broken too, ans it waits forever for that.
I dont have any schematics or any other information, so I'am stocked here.
S
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