Allbrite and controller work with RCA but not VGA

**lookinco** · 10-01-2004, 04:11 AM

Yes I have. I can actaully see the screen VERY faintly. For example when I move the mouse I can see it faintly moving around. When I click on start I can see a part of the screen change color.

**mushin** · 10-01-2004, 04:34 AM

Really? Wierd! I'd say it was the backlight, except the RCA input works. Got me.

**lookinco** · 10-01-2004, 04:44 AM

It's not the backlight. The back light is bright as the sun. Also RCA works, so i doubt if it would be the LCD panel's fault.

**davesaudio2** · 10-02-2004, 08:35 PM

does your eprom match the table in the manual?

**lookinco** · 10-03-2004, 01:42 AM

what's EPROM ?

**mushin** · 10-03-2004, 02:27 AM

EPROM is a type of programmable ROM, usually for firmware and such. I believe oftentimes a controller has to be flased with the right firmware for the panel it's to be controlling. I don't think this is the issue for you though, since your RCA input works, the controller seems to drive the LCD just fine. Then again, I'm not an expert in these matters, so I could be mistaken.

**alti** · 01-04-2005, 03:51 PM

Bringing this tread back hopeing to figgure out this problem.

Update on the history.

Sent the lcd, controller and cable in to be fixed and after about 2 months I received them back and the lcd was smashed apperantly in shipping. I assumed the problem was fixed as the vendor I purchased the equipment from told me it was and I could not tell be looking at the smashed lcd. So I started the search to replace the lcd. And i found another allbrite in new condition. When I received the new panel and hooked it up, to my horror I got the same result!!! it works in RCA but not with VGA. At this point I think I am ready to cry

anyway, hopeing someone might see this who has another idea. There is nothing wrong with the lcd that i can determine as it works fine in RCA, I can use the OSD and everything. My guess is that it must be the cable or the controller itself. I am working on determining the pin outs of the cable and matching it to the setup of another controllers spec sheet to see if the connections are matched up the same, will post what i find.

anyone know what pins RCA uses on the cable? (vsync, hsync, r1,g1,b1, gnd ect??) I trying to narrow the problem down to either the cable or controller and I am thinking that if i can deterime that using the RCA uses all of the pins on the cable that VGA does then it would not be the cable since the RCA output works, thoughts?

Thanks

**alti** · 01-04-2005, 05:36 PM

Ok I have the pin outs here is the overall
Function to Function
Signet controller CN1 NL8060BC26-17
GND -> GND Ground
Clock -> DCLK Dot clock
GND -> GND Ground
Hsync -> Hsync Horizontal sync.
Vsync -> Vsync Vertical sync.
GND -> GND Ground
R2 -> R0 Red data (LSB)
R3 -> R1 Red data
R4 -> R2 Red data
R5 -> R3 Red data
R6 -> R4 Red data
R7 -> R5 Red data (MSB)
GND -> GND Ground
G2 -> G0 Green data (LSB)
G3 -> G1 Green data
G4 -> G2 Green data
G5 -> G3 Green data
G6 -> G4 Green data
G7 -> G5 Green data (MSB)
GND -> GND Ground
B2 -> B0 Blue data (LSB)
B3 -> B1 Blue data
B4 -> B2 Blue data
B5 -> B3 Blue data
B6 -> B4 Blue data
B7 -> B5 Blue data (MSB)
GND -> GND Ground
DTMG -> DE Data enable
GND -> X
VCC -> VCC Power supply
VCC -> VCC Power supply
VCC -> X

There is a much more detailed overview in the spreadsheet attached.

Looks ok on the surface to me is there something i am missing? The following are not connected from the lcd along with a bunch of grounds, do they need to be?
38 DPS Scan directrion select Note 4 DPS: High = normal scan low or open = reverse scan
41 MODE Timing mode select Note 2 2. MODE: H = DE mode

anyone know what the difference is in normal and reverse scan???

**eCar™** · 01-05-2005, 05:45 AM

I don't think the problem is between the controller and LCD. If it works with RCA, then the two are setup and connected properly, I think. The type of input to the controller does not change anything at the controller-->LCD interface. The LCD does not care what kind of signal you are supplying to the controller. It's up to the controller to convert RCA, VGA, S-Video, whatever, to the type of signal that the LCD needs. And then you must have the proper cable to get that signal to the LCD. You appear to have that.

So, I guess that your controller is having trouble with the VGA signal you are sending it. Try a different refresh rate maybe? I've never had to adjust frontporch, backporch, etc. But maybe you do?

FWIW, I counted the number of wires in my controller-->LCD cable, and I have 27. I think I counted 25 in yours. I think one of the extras on mine is the DPS. I haven't bothered to chart all the connections on mine, or look over yours, because mine works fine, and I don't believe there is a problem here for you either.

As far as the reverse scan thing, it just flips the picture 180°. I'm pretty sure that the NEC panel is upside down in the AllBrite housing anyway. If there is an "up" to the housing.

In my case, the AllBrite stickers (and warranty seals) are upside down when he displayed image is rightside up. But I'm pretty sure that the NEC is rightside up also. The Hirose connector is on my left, at the rear of the panel, while I am viewing the monitor. According to the datasheet this is the normal scan direction. So, I assume that #38 on my Hirose connector has VCC to it.

So, I guess that your image is rightside up, along with the stickers. But the Hirose connector is at your right.

There is a difference in the viewing angles from up to down, so it may be better to have it one way or another. In a car setup, I think it would be best to have it reverse scan (DPS open, like yours).

**alti** · 01-05-2005, 12:16 PM

Thanks for the reply I am sorry if my information is jumbled together above.

I have tried different refresh rates including 60 (i use by default), 70, 72,75, 80. Nothing seemed to work there. I also have tried it with 3 different computers my laptop (use as default for testing to use the switch lcd/crt Fn), my carputer setup (which is still on my desk), and my desktop. My laptop has a mobile ATI radeon, my desktop a ATI 9600 and my carputer has a onboard Nvidia nForce2. Have tried booting all 3 cold with the setup and the bios/windows boot screen do not even show.

What is the timing mode select? Is that possibily the culpert? I saw in the NEC lcd's documentation what you were saying about the reversed screen and I mine is upside down as well the hirose connector is on the left and the angled part with the 3 nuts is on the bottom.

I am not sure what frontporch and back porch are but i am going to google it and give it a try

here are 3 videos that i have put up, hopefully this will help show what i am talking about.

I have noticed that the status light on the OSD starts flashing yellow and red as soon as I connect the VGA connecter. The only way that i can get the LED to stay green with the VGA cable connected is to plug it in to my desktop while it is off and do a cold boot. Irronicly it does not seem to matter what the light is doing as the display always reacts the same way.