16x2 W&B RasPi LCD no letters...

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haincha
 
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16x2 W&B RasPi LCD no letters...

Post by haincha »

Okay, I got the kit and put it all together. Have it soldered to what I believe to be correct. When I run the code, it flashes the LCD and when I touch the buttons it displays them in the terminal window. However, no text is showing up on the screen whatsoever.

Thoughts? I am using a 512MB RasPi.

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adafruit_support_bill
 
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Re: 16x2 W&B RasPi LCD no letters...

Post by adafruit_support_bill »

Post photos of the front & back of the shield & we'll double check the assembly.

haincha
 
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Re: 16x2 W&B RasPi LCD no letters...

Post by haincha »

https://www.dropbox.com/s/3gm83audpu9ti ... .38.52.jpg
https://www.dropbox.com/s/2giksjj631gi3 ... .57.00.jpg
https://www.dropbox.com/s/l4zpsyg3b0hbv ... .57.21.jpg
https://www.dropbox.com/s/yscemigcvchb3 ... .38.08.jpg

The board looks much worse now than it did. I attempted to unsolder the lcd board and solder it back on. Now, I think I have officially killed the board. The buttons still work in the python script test, however, now the screen does not flash at all. Not sure if it is somehow not getting power anymore, the only thing I changed was I used 16 pins instead of 18. I had two dummy pins soldered in before, since it is a blue&white LCD.

I don't have a whole lot of faith in this, and as it was my first soldering experience. I will chalk it up to there is a bit of a learning curve. Any chance it is salvageable? I know there are no Pi issues. I have a 2.8" touch screen that is connected and working as intended.

I will probably have to order a new kit when they become available again, and I am okay with that. Gotta learn somehow, even if it doesn't go as planned the first time.

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adafruit_support_bill
 
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Re: 16x2 W&B RasPi LCD no letters...

Post by adafruit_support_bill »

The board looks much worse now than it did. I attempted to unsolder the lcd board and solder it back on.
All things considered, It doesn't look all that bad. :) Removing a display with all those pins is not an easy task.

The fact that the buttons work indicates that the i2c communication and port expander chip are functioning. With the board powered up, take a jumper wire and ground pin 16. Does the backlight light up?

haincha
 
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Re: 16x2 W&B RasPi LCD no letters...

Post by haincha »

So, I got my second one in the mail, assembled. Got the same problem. Then I messed with the contrast. It started working...

I am wondering if I would have messed with the contrast on the first one before I desoldered and really broke it. It may have worked...

So, needless to say. I had my learning experience and now have a working plate!

Thanks!

maurifree
 
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Re: 16x2 W&B RasPi LCD no letters...

Post by maurifree »

I Have it soldered correctly. When I run the python code, it flashes blue on the LCD and when I touch the buttons it displays them in the terminal window. However, no text is showing up on the LCD screen whatsoever. Only a line of blocks. My LCD that I got with the plate also looks different to the ones in the pictures as this only has connectors on one side. Have I done something wrong? Can someone please assist me? I am using a 512MB RasPi ModB.

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adafruit_support_bill
 
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Re: 16x2 W&B RasPi LCD no letters...

Post by adafruit_support_bill »

@maurifree - Post photos of the front and back of your board and we will check the assembly.

maurifree
 
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Re: 16x2 W&B RasPi LCD no letters...

Post by maurifree »

adafruit_support_bill wrote:@maurifree - Post photos of the front and back of your board and we will check the assembly.
Here they are
https://drive.google.com/folderview?id= ... sp=sharing

Also the buttons work and the lcd backlight comes on. Just get blocks keep showing on the display instead of characters. Any pointers on what to do to fix ths are welcomed.

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adafruit_support_bill
 
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Re: 16x2 W&B RasPi LCD no letters...

Post by adafruit_support_bill »

Most of the soldering looks very good. But the joints on the display header are not complete. The solder should flow all the way around the pin and pad. An intermittent connection on one of those pins could explain the lack of text display.

maurifree
 
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Re: 16x2 W&B RasPi LCD no letters...

Post by maurifree »

adafruit_support_bill wrote:Most of the soldering looks very good. But the joints on the display header are not complete. The solder should flow all the way around the pin and pad. An intermittent connection on one of those pins could explain the lack of text display.
Hi,
This is NOT a soldering problem. I took another LCD display 1602 and just held it against the pins of the faulty LCD. The characters then showed correctly on the LCD that I was pressing against the pins.
So it i certain that you sent me a faulty LCD display and now the plate is also ruined as the bad LCD is soldered in and is now impossible to desolder without doing so much damage.
How do I get this replaced as I am in Australia and sending it back is not economical?
Thanks
maurifree

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hiduino
 
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Re: 16x2 W&B RasPi LCD no letters...

Post by hiduino »

Did you try the contrast adjustment dial?

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adafruit_support_bill
 
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Re: 16x2 W&B RasPi LCD no letters...

Post by adafruit_support_bill »

This is NOT a soldering problem.
That may not have been the immediate cause of the display problem. But those joints are clearly not adequate for a display header. The display is a relatively heavy component and is attached only by one edge. Your solder connections must be both mechanically and electrically sound or they will fail.

If you contact [email protected] we can send you a replacement kit. Please review our soldering guide in the mean-time: http://learn.adafruit.com/adafruit-guid ... -soldering

maurifree
 
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Re: 16x2 W&B RasPi LCD no letters...

Post by maurifree »

adafruit_support_bill wrote:
This is NOT a soldering problem.
That may not have been the immediate cause of the display problem. But those joints are clearly not adequate for a display header. The display is a relatively heavy component and is attached only by one edge. Your solder connections must be both mechanically and electrically sound or they will fail.

If you contact [email protected] we can send you a replacement kit. Please review our soldering guide in the mean-time: http://learn.adafruit.com/adafruit-guid ... -soldering
Thanks. Btw I did try to improve the soldering and resoldered all the contacts again. However this did not fix the problem. I also metered all the connections and they we good. This problem is definitely a faulty LCD display chip.
Thanks for the offer to replace this.

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