LCD Backlight Only

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pha
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Joined: Thu May 16, 2019 5:11 pm

LCD Backlight Only

Postby pha » Thu May 16, 2019 5:16 pm

Thank you for a great product, but the LCD seems to be faulty, it only displays backlight when I run the default LCD example included in the IDE. I ordered two and both are like this? Please advise. (Yes, the LCD is connected on the back with long pins.)
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kwagyeman
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Re: LCD Backlight Only

Postby kwagyeman » Thu May 16, 2019 6:35 pm

Can you provide more information on the issue? Your first statement implies that the backlight is fine. Note that the backlight can be turned off using PA5 (P6). If you are using that pin in your code it will turn off.
Nyamekye,
pha
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Joined: Thu May 16, 2019 5:11 pm

Re: LCD Backlight Only

Postby pha » Fri May 17, 2019 9:09 am

I am new to this maybe I am not using the correct expressions. When I connect the LCD to the back of the M7 board, and run the LCD code included in the IDE, the LCD turns white and nothing else. The camera view is shown in the IDE and not on the LCD. You refer to the P6, the LCD example included in the IDE 2.2.0 does not have that. I am sure you know the code better than any of us, but I include it here for your reference. Thank you for a great service.

Code: Select all

# LCD Example
#
# Note: To run this example you will need a LCD Shield for your OpenMV Cam.
#
# The LCD Shield allows you to view your OpenMV Cam's frame buffer on the go.

import sensor, image, lcd

sensor.reset() # Initialize the camera sensor.
sensor.set_pixformat(sensor.RGB565) # or sensor.GRAYSCALE
sensor.set_framesize(sensor.QQVGA2) # Special 128x160 framesize for LCD Shield.
lcd.init() # Initialize the lcd screen.

while(True):
    lcd.display(sensor.snapshot()) # Take a picture and display the image.
    
 
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iabdalkader
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Joined: Sun May 24, 2015 3:53 pm

Re: LCD Backlight Only

Postby iabdalkader » Fri May 17, 2019 9:30 am

Hi, can you double check the pins and make sure they are all connected ? Please don't use any other shield when testing (some shields use the same pins used by the LCD shield). Also can you tell me which firmware version are using ? And please include a picture of how you connect the LCD shields (just to be sure, I've seen more than a few issues with connecting the shield).

I don't think there's an issue with the LCD shields you have, it could be a short in the camera's pin header. If you have a multimeter you should test the SPI pins for shorts.
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kwagyeman
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Re: LCD Backlight Only

Postby kwagyeman » Fri May 17, 2019 11:38 am

Turning white means the display is powered but nothing getting data. Pictures will help us debug.
Nyamekye,
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jcarlos
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Location: Spain

Re: LCD Backlight Only

Postby jcarlos » Sun May 19, 2019 4:08 pm

pha wrote:When I connect the LCD to the back of the M7 board, and run the LCD code included in the IDE, the LCD turns white and nothing else. The camera view is shown in the IDE and not on the LCD.
I have the same problem with my LCD Shield and OpenMV H7. Mi first test was yesterday (2019/05/18)

I have Windows 10 x64 + OpenMV IDE 2.2.0 + firmware 3.4.1

I am new to this too.

My "assembly". Perhaps it is incorrect? (VIDEO)
https://vimeo.com/337156493


My test with the LCD Example (VIDEO)

https://vimeo.com/337156676


Any pictures:

Image

Image

Image

If you need more, just ask me!

Thank you in advance!!

JC
JC
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iabdalkader
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Re: LCD Backlight Only

Postby iabdalkader » Sun May 19, 2019 4:35 pm

@jcarlos These pins need to be soldered to the board to make electrical connections, it's not enough to just put them there. Do you know how to solder ? If not you should ask someone for help. Note be careful which type of pins you choose, they're very hard to desolder. Soldering those short pins on the back won't allow you to use other shields on the front, if you don't need other shields that's fine, otherwise you should use the longer pins so the camera with soldered pins looks like this:

https://cdn.shopify.com/s/files/1/0803/ ... grande.jpg

EDIT: Oh and shields should Not be hot-swapped (connected to the camera while it's powered on). You should disconnect the camera from USB first before connecting shields.
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jcarlos
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Location: Spain

Re: LCD Backlight Only

Postby jcarlos » Sun May 19, 2019 4:56 pm

Upps!! Well. Sorry for my ignorance! I am an absolute newbie with Open Hardware and so... :oops:


As I reread your answer more carefully, I understand that I ONLY need to solder the long pins. And then, alternatively, I can connect / disconnect the shields without any additional welding, right?




-----------------------------------

I had the naïve hope that the welding was not essential and so easily change the shield.

I must admit that I feel disappointed. I expected a more plug / unplug and play architecture.
But the fault is only mine and I will get over it.

No. I do not know how to weld but I can find help. I know people with enough experience. However, such a drastic solution frustrates me. Is there an alternative to welding, even with the use of cables?
iabdalkader wrote:you should use the longer pins so the camera with soldered pins looks like this
If the longer pins are soldered (like in your picture), can i connect/disconnect without soldering the shields (Wifi Shield/LCD Shield)?

Thanks in advance!
JC
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iabdalkader
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Re: LCD Backlight Only

Postby iabdalkader » Sun May 19, 2019 5:32 pm

We don't solder headers anymore because customers prefer different types of headers (or no headers at all :roll: ) and yes if you solder the headers you can connect and disconnect shields.
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jcarlos
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Location: Spain

Re: LCD Backlight Only

Postby jcarlos » Sun May 19, 2019 5:50 pm

Thank you very much for your VERY FAST support! It is amazing!!

I will look for help to solder the pins for testing the material as soon as possible. Once again I feel my ignorance about these fundamental technical aspects. Sorry! :oops: :oops: :oops: :cry:

JC
JC
pha
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Joined: Thu May 16, 2019 5:11 pm

Re: LCD Backlight Only

Postby pha » Mon May 20, 2019 4:31 am

Had the exact same issue and setup as jcarlos, thanks for solving the issue :-)

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