Help with showing characters on my LCD screen!

[aiux]

Hello!
I bought a LCD screen https://www.adafruit.com/products/398, and after soldering, got to test out the script you guys provided at
https://github.com/adafruit/Adafruit-US ... r-Backpack.

I am using the USB connection to my Raspberry Pi, and discovered that the device file set is at /dev/ttyACM0 or /dev/ttyACM1.

However, when I run

python matrixtest.py /dev/ttyACM0,

the screen did not show any characters up, but only changes the color on the screen. What am I doing wrong?

[adafruit_support_rick]

Do you mean that you bought this LCD?
https://www.adafruit.com/products/784
The one you linked to does not include the Serial/USB Backpack.

Please post clear, detailed pictures of both sides of the display, showing your soldering.

[aiux]

Yeah I bought that..oops.

Here are some photos:

2014-05-25 07.13.14.jpg (864.59 KiB) Viewed 626 times

2014-05-25 07.14.22.jpg (973.67 KiB) Viewed 626 times

2014-05-25 07.14.59.jpg (856.83 KiB) Viewed 626 times

[adafruit_support_rick]

You've bridged the solder between pins 2, 3, 4, and 5. It can't work if those pins are all connected together like that. You'll have to remove that extra solder. I suggest using a solder sucker:
https://www.adafruit.com/search?q=solder%20sucker

We have a nice tutorial on soldering here:
https://learn.adafruit.com/adafruit-gui ... ring/tools

[aiux]

Hi!

Thanks to your advice I was able to display characters now.
However, I discovered that the screen fades away most of the time and the characters are barely visible. What could be the issue here?
Also, I am using mpdlcd with lcdproc to display my music information, but lcdproc keeps interrupting the song name display with it's own messages. How do I remove it?

Thanks again!

[adafruit_support_rick]

I'm not familiar with lcdproc - maybe someone else here has some ideas.

However, I discovered that the screen fades away most of the time and the characters are barely visible. What could be the issue here?

Is the backlight fading out, or is the screen contrast going away? If you look at a different angle at the screen, can you see the characters?
This could still be a soldering issue. Post some new pictures.

[aiux]

Hi, the characters would fade away and back again. The backlight brightness was also rather inconsistent.
Here is a photo of the fixed soldering:

2014-05-28 18.19.19.jpg (892.45 KiB) Viewed 601 times

[adafruit_support_rick]

The soldering looks good. But what's this thing? Looks like it doesn't belong there...

[aiux]

It's just dust!

Anyway, could the power supply be responsible for the fading?

[adafruit_support_rick]

You're just using USB power, right?
You could try plugging it into a computer to see if the problem goes away. It will just look like another serial port:
https://learn.adafruit.com/usb-plus-ser ... g-with-usb

[aiux]

Hi, thanks, will try that out!

[aiux]

Hello! After some tinkering, I discovered that it was actually a faulty USB cable, which I got it replaced.
It is working nicely now!

Some tips for people:
If you are encountering errors when installing the driver on Windows 8, hold shift and click on Restart in the Charms menu. Afterwards, go to Troubleshooting, Advanced Settings, and Restart. Afterwards, select option 7 to disable driver signature enforcement.

To test a basic message, ignore the fancy terminal stuff! Once you installed your driver, just take note of the COM port name, and then do this:

Code: Select all

echo hello world! > COMNAME

and the message should appear :)

I have one last question! Does the LCD screen provide UTF8 support?

[adafruit_support_rick]

I have one last question! Does the LCD screen provide UTF8 support?

I think it's just ASCII.