2.2" 18-bit color TFT LCD display with microSD card breakout

[alemela]

Hi,

I recently bought the 2.2 display for mounting on raspberri pi.
I followed the tutorial here: https://github.com/notro/fbtft/wiki but screen seems not to respond as expected.
I'm wondering if I wired it wrongly. I wired it twice as per https://github.com/notro/fbtft/wiki/LCD ... dafruit-22 (except for led pin which I put in GPIO23 as per driver layout) .
I can power the backlight off and on correctly from command line but when I try to run graphic tests or show any kind of image lcd behaves funny.
Sometime it powers off, other times it get a little darker, other times it shows colored lines and other times nothing at all.
I'm a bit worried about the lack of coherency in screen response to the same input.
Does somebody know the exact wiring of the LCD for PI?
How can I check if the lcd is defective?

Thanks

[adafruit_support_mike]

Try connecting the LCD to an Arduino and running the 'graphicstest' sketch included with that library: https://github.com/adafruit/Adafruit_ILI9340

That will give us a better idea of whether the TFT works.

[alemela]

Hi Mike,

Thank you for your kind response.
Unfortunately I don't have the opportunity to connect the LCD to an arduino as I don't own one and nobody I know does.
Do you have an alternative method?

Thank you,

alemela.

[adafruit_support_mike]

Post a photo of your hardware and connections, along with a view of the screen when it's misbehaving if you can get one. We'll see if that tells us anything.

[alemela]

Hi,

Here I attach three photos.
First two are the connection to gpio strip coming from the screen, third is the connection to the screen.

[alemela]

Here a photo for reference on how the gpio strip is conected to the r-pi, just in case you are wondering if I plug it in the wrong way.
I also have a little video of the bahavior of the screen but it's bigger than forum attachment max size, you can retrieve it here:
http://ul.to/437cg2x5

I ran several times the test and the screen behaved different 3 of 4 times. None of the times it showed the os desktop.

Thanks,

Alessandro.

[alemela]

@ adafruit_support_bill/adafruit

Guys, I really need to know if the screen is wrong or it's just me. My project is stuck due to this issue.
Could you please tell me something more? Is there a proper support channel I can use for moving this forward?

[M]

I'm having a similar issue, this time on an Arduino. The example program runs but the LCD gets scrambled halfway through.

I narrowed it down to the presence of the SD card. Without an SD card it runs fine - with the card, it fails. Different cards make it fail in different places. The SD CS line is explicitly driven high so theoretically the SD card should not be interfering with the SPI bus. (Setting SD CS low while accessing the display makes the inteference worse.)

Looking at the SD card standard, the un-used data lines should be held low when using SPI mode. This breakout board lets them float. Perhaps the SD card is seeing data that encourages it to output data on the MOSI line?

[adafruit_support_mike]

@M: Please start a new thread for your issue. Trying to debug two hardware problems in the same thread just invites confusion.

@almela: Sorry for the late reply. It's very difficult to trace those connections through three photos and a ribbon cable.

Try plugging the display into a breadboard and running the jumper wires directly to the RasPi's GPIO pins. That will eliminate about three sources of possible confusion.

[alemela]

Hi,

I don't have a breadboard, so I used a protoboard.
Here are the photos.

The behavior of the device is still the same.
I can turn it off and on ok but there's no way to have the output shown in the screen.

[alemela]

Hi,

I've sorted it out... and it was a very basic stuff...
I was loading the driver for the old screen...

I loaded the proper one and the screen worked fine.

Thanks for the support.

[adafruit_support_mike]

Glad to hear you got it working.