beaglebone black lcd display brands

And here"s the repo with the dts file along with some notes on how to get it working with that image: https://github.com/JamesHagerman/4D-7in-LCD-Cape-Fixes-for-3.12

This 7" touchscreen cape creates a fully integrated system when combined with your BeagleBone Black. Provides full Angstrom support for easy BeagleBone prototyping and projects. A secondary set of header pins gives built-in stacking cape-ability.

The Cape for 7 inch displays is neat interface to connect the Waveshare 7 inch displays to your Beaglebone Black. We have not tested any other LCD"s, but the interface is designed for 7 inch resistive touchscreen LCD displays

7 Inch Touch LCD Cape for BeagleBone Black is a complete display solution for BeagleBone Black. The package includes 7" Display, BeagleBone compatible cape with display interface, USB to TTL cable with PL2303, 5V 2A Power adapter, USB Type A to mini B cable, 40 pin FFC cable for display and a pack of screws.

Description:The 7.0” resistive touch LCD touch from 4D Systems is a cape specifically designed for the Beaglebone Black, and provides a 7.0” primary display for the BBB for direct user interaction and information display. The Beaglebone Black connects directly to the back of the LCD cape, and provides everything the cape requires such as power and display signals. The Beaglebone Black LCD cape features 7 push buttons below the screen, LEFT, RIGHT, UP, DOWN, ENTER, RESET and POWER, along with 2 LED’s to indicate Power and User Status. Mounting the cape is easy with the 4x 3.5mm mounting holes present on it, enabling standard M3 or #6-32 screws to fasten the the LCD cape as required.

The 4D 7.0” LCD CAPE which features a 7.0” TFT LCD 800x480 resolution display,is a cape specifically designed for the Beagle Bone Black (BBB). It provides a 7.0” primary display for the BBB for direct user interaction and information display, along with the ability for additional CAPES to be attached at the same time.

The BBB connects directly to the back of the 4DCAPE-70T, and allows everything the CAPE requires such as power and display signals. Another CAPE can be added to the secondary connectors on the back of the module if required.

The 4D 7.0” LCD CAPE features 7 push buttons below the screen, LEFT, RIGHT, UP, DOWN, ENTER, RESET and POWER, along with 2 LED’s to indicate Power and User Status (normally heartbeat).

Continuity loss? Used a multimeter to check connections to the FPC. All looks good, nothing strange. Somewhere in between this testing the LED backlight wasn"t lighting up when I connected the LCD. Whoops! I burn 4 LED drivers in the process (but they seem to have open LED "protection"?). Add a 16V Zener across the LED lines to prevent re-occurrence. The LEDs are in a 3-series (and currently unknown parallel lines) configuration and draw 9.5V.

Maybe some signal integrity issues? It"s Scope time.Put cape on the BBB, LCD disconnected. Probe signal pins. The highest frequency signal, PCLK (@30 MHz) appears clean enough. Data lines look good as well.

Look at the LCD panel under strong light. Was able to make out the Beagle on the screen, once again. The screen looks stable (a direct consequence of the fact that the signals look good on the scope).

Okay, now that we know the issue, we should need to just add some bypass caps to fix it? Sprinkle a few 10uF 0805 ceramic caps, one before the LED driver and the other across the LED driver output still the display appears to be as unstable as it was before.

At this point I asked in the HaD channel, and with feedback that maybe the onboard 3.3V of the BBB is not supplying enough current to power everything, try to power the entire cape with a 1117-3.3 fed from the 5V of the BBB. An unstable display, still.

I look at existing cape reference designs (CircuitCo BB-VIEW7 and 4DSystems 70T) and find that they power their LED drivers off the 5V rail, and not the 3V3 VDD rail. Maybe they knew something about ripple from LED drivers affecting the LCD supply?

I also read official Linux devicetree "bindings" as indicated in the code"s comments and I defined my LCD panel device node panel. I also used node port to connect it to the frame buffer device node fb.

After I built the Linux image and used it to boot the device I noticed that frame buffer device /dev/fb0 was created, but display shows nothing! It is white and is flickering a bit.