Psone screen - Inverted colors

[schmellyfart]

A little background info: I've been working on a project for my Uncle these past few months. All it really is, is a battery powered psone screen in a new case. It will be used as a monitor for his camera, so the psone screen is mounted upside down, and the lcd is also flipped around to reverse left and right to accommodate for the lens on his camera.

It was going well until I trimmed off the connectors at the bottom of the board so I have room to mount the screen and redrilled new screw holes to mount the board. That's when the LCD began to invert the colors. I've tested multiple LCDs and mobo's and have confirmed that this mobo is where the problem lies. The screen is also getting plenty of power, as the other mobo I tested works on the same power supply. I would like to fix this mobo, but if it comes down to it I will swap it out.

As you can see in the following pics, I have not trimmed much of the board. I did not cut into any components.
Please excuse the quality, my cell phone camera is all I have access to at the moment.




Here is a clearer pic of where I trimmed the bottom of the screen(the tiny red line ):

[Hifeno]

Dude I had this problem with one of mine as have countless others and no one ever answered any of us how what might be causing it. I never even cut my board it just started doing it even with wall power.

[Snow_Cat]

Is the polarizing film (semi-trasparent layer) flipped or rotated? That would do it.

[schmellyfart]

Dude I had this problem with one of mine as have countless others and no one ever answered any of us how what might be causing it. I never even cut my board it just started doing it even with wall power.

Dang, thats no good.

Is the polarizing film (semi-trasparent layer) flipped or rotated? That would do it.

I believe the polarizing film on the PSOne screens is glued on. See, the thing is that it worked perfectly (regular colors and everything) until I cut off the tiny portion of the board and redrilled some new mouting holes

[Snow_Cat]

Can you show us an image with a pure R,G and B component displayed?

I'm thinking that either the colour isn't being decoded correctly from the console, or somehow the output to the screen has been inverted.

Spoiler:

You are confident that no traces were cut, so lets try to find what SMDs might have come loose.

[schmellyfart]

Do you mean inputting RGB into the screen and seeing if that works? If so, I don't have anything that outputs RGB.

I am not so sure that no traces were cut. I will take better pics of my new mounting holes, but I have a feeling that's where the problem lies..

[Snow_Cat]

No, I meant in a colour test pattern. This way we could see if the different colour channels are being transformed differently.

Spoiler:

[schmellyfart]

How do I do that?

[Snow_Cat]

(headdesk)

"?noitatSyalP"

[schmellyfart]

A little background info: I've been working on a project for my Uncle these past few months. All it really is, is a battery powered psone screen in a new case. It will be used as a monitor for his camera, so the psone screen is mounted upside down, and the lcd is also flipped around to reverse left and right to accommodate for the lens on his camera.

The colors were showing properly before the trimming - with the lcd reversed.

[Snow_Cat]

Sorry;
It was late and I was not thinking clearly. I saw the picture and thought 'There it is!' before the more powerful 'I am hungry' interrupted knocking my train of tought off the rails and I latched on to the inverted text instead of the board connection.

The test pattern can be taken from a PC, or other source with a appropriate output.

The direction I think my thought pattern was going.

Spoiler:

The OpenLowVoltageD;ifferentialSignalingDisplayInterface is unerable to one (or more) lines being shorted to ground.

The pinout of the FFC cables are typically {VCC, nc, {GND, Dn-, Dn+}x4-8, nc, GND}x1, if the cable slips one place then the D+ and D- are swiched and the data is then inverted with the 'other' line shorted to ground. The controller/screen can not leave the default unbalanced mode since this also sisrupts the DisplayDataChannel that would carry the ExtendedDisplayIdentificationData.

Another possiility is that cutting, handling, and a broken solder joint has disconnected the line that sets the DCBAL register. Strange, but not completely outside the realm of possibility.

In the balanced operating modes, in addition to pixel and control information an additional bit is transmitted on every signal line during each cycle.
This bit is the DC Balance bit (DCBAL).
The purpose of the DC Balance bit is to minimize the short- and long-term DC bias on the signal lines.
This is achieved by selectively sending the pixel data either unmodified or inverted.

...

If the running word disparity is negative and the current data disparity is positive, the pixel data shall be sent unmodified.
If the running word disparity is negative and the current data disparity is zero or negative, the pixel data shall be sent inverted.
If the running word disparity is zero, the pixel data shall be sent inverted.

• http://www.tu-chemnitz.de/informatik/RA ... penldi.pdf

see also http://www.national.com/an/AN/AN-971.pdf

Scratch that. I did what I should have in the first place and looked for the datasheet. It uses an analogue RGB, not a LVDS interface. The pinout is immune to the failure described above.

If you power only the backlight is the screen dark?

compart.plActive matrix color TFT LCD module (includes samsung datasheet)
Catologue page

[Archon276]

I dont know why the picture is backwards but as far as the inverted colors go try using a different power supply. mine had inverted colors tool and bacteria told me to try a different one so i used the official sony one and it fixed the problem. hope that helps

[Haunted360]

Well, why do you have all those wires going form Traces / Resistors etc to wherever?

That would be your issue there...

[gamax92]

Yeah if you cut traces wont all the wires be around the outside.
Please explain why all those different wires are there.

Oh for rgb on a monitor dont you just only these wires.

Spoiler:

Pin Name Function
1 RED Red video
2 GREEN Green video
3 BLUE Blue video
5 GND Signal ground

[schmellyfart]

Hey guys sorry for the late reply, been busy with school.

I dont know why the picture is backwards but as far as the inverted colors go try using a different power supply. mine had inverted colors tool and bacteria told me to try a different one so i used the official sony one and it fixed the problem. hope that helps

I don't mean to be rude as you are trying to help, but did you even read the first post? My reasons for the reversed image are in the first paragraph of the first post. My other PSOne screens work flawlessly on the same power supply. Its been a while, but I believe the screen also inverted the colors when running on the sony power supply.

Well, why do you have all those wires going form Traces / Resistors etc to wherever?

That would be your issue there...

The wires on the back of the mobo are power, ground, and video. The wires on the front are from the led mod, they aren't soldered to the board as they appear to be.

Yeah if you cut traces wont all the wires be around the outside.
Please explain why all those different wires are there.

Which wires?