LCD wiring

[ericgbz]

Hi,

I'm completely new to electronics and would need some help in getting my LCD to work. Unluckily, like majestic, tomsupergreen and some others I ended up with a PCB too big to fit inside a GB shell out of the box.
Anyway went ahead with these steps:

1 - unsolder display controller's XL1509-5.0e1 then solder red cable from pin 2 --> pi0's pp1
2 - solder black wire --> pi0's pp6
3 - solder yellow wire --> pi0's TV pin
4 - power up pi0

Here I was able to see raspbian's boot logs followed by a login prompt on the LCD, so I unplugged the LCD's ribbon cable from its socket and got rid of the lcd plastic shell + screen protector.

But after connecting back the ribbon cable to the socket I'm left with white pixels all over the LCD. It's a bit tricky because the ribbon cable's socket is wider and has more pins than the ribbon itself.
I tried to carefully fit the ribbon like it was initially, but no matter what I do from now I'm not able to see raspbian's login screen.

Is there something more I can attempt or should I buy another screen? Any help appreciated.

[n.marek]

I have the same screen. With the same stupid wider connector than the ribbon cable. The ribbon goes all the way to the right, the LCD won't show anything but white light if you're trying to get the ribbon in while it's on. Once you get the white light all over the LCD, restart the Pi and it should work.

Also you can cut the button side of the board (after you finished setting up the display with the buttons - you will lose that).

[ericgbz]

n.marek, the result is the same after rebooting the Pi. Here is a picture of my setup:



Could it be a software issue where a driver needs to be configured in raspbian? I have ssh access to the Pi over USB

[n.marek]

I am not sure

1. I have a jumper wires (red and black on my picture) connected to the pins where the desoldered chip was. I don't know if that could help, but you don't have the black there (ground).

2. Play a bit more with the ribbon. (Gently)

3. You could try to put the chip back on and test it again with 12V.

Sorry, not sure what it could be

[JujuPi]

I am not sure

1. I have a jumper wires (red and black on my picture) connected to the pins where the desoldered chip was. I don't know if that could help, but you don't have the black there (ground).

2. Play a bit more with the ribbon. (Gently)

3. You could try to put the chip back on and test it again with 12V.

Sorry, not sure what it could be

You need to secure the ribbon as much as you can to the left side on that photo. DO NOT DO IT WHILE IT IS ON. I burned my board by doing so. The input smoked...

Also make sure you press that securing tab in forward otherwise you will not have a solid connection. This happened to me. Take it out, give it a blow, then put it back in as said. AS MUCH AS YOU CAN TO THE LEFT AND GENTLY

[n.marek]

I am not sure

1. I have a jumper wires (red and black on my picture) connected to the pins where the desoldered chip was. I don't know if that could help, but you don't have the black there (ground).

2. Play a bit more with the ribbon. (Gently)

3. You could try to put the chip back on and test it again with 12V.

Sorry, not sure what it could be

You need to secure the ribbon as much as you can to the left side on that photo. DO NOT DO IT WHILE IT IS ON. I burned my board by doing so. The input smoked...

Also make sure you press that securing tab in forward otherwise you will not have a solid connection. This happened to me. Take it out, give it a blow, then put it back in as said. AS MUCH AS YOU CAN TO THE LEFT AND GENTLY

You might be right, the black ribbon lock doesn't look pushed in. I played with my ribbon while it was on, I guess I was lucky it didn't burn