STM32F746G-DISCO display panel choice and alternatives

[ray23]

Posted on January 16, 2017 at 18:53

I bought a STM32F746G-DISCO board and have decided that a board like it will fit the needs of my project. Are there any companies that make development boards with this MCU that can use a larger LCD display? The disco board has a 40 pin RGB interface with the touch pins combined within the 40 pins and I can't seem to find a larger LCD panel that has this connector. Do any companies make other boards for this MCU?

#stm32f7 Note: this post was migrated and contained many threaded conversations, some content may be missing.

[Tesla DeLorean]

Posted on January 16, 2017 at 19:56

http://www.waveshare.com/open746i-c-standard.htm

 

The Arduino OTTO STAR might also provide a standardized connector method for the LCD moving forward using a Mictor header. Seems to have been a bit dead in the water for a year, but ST still thinks it is alive, and would likely take an F7 with a BOM change.

http://www.arduino.org/products/boards/arduino-star-otto

 

The panel makers do a whole lot of build to order, you should check who built the panel for the DISCO and ask them what else they have.

[ray23]

Posted on January 16, 2017 at 21:01

I tried to email their sales link they provided and it was returned.  The probably only take email from company accounts.  I am a consultant and am trying to build a prototype so I only need one.  

[Tesla DeLorean]

Posted on January 16, 2017 at 22:02

The EVAL series boards tend to have more options, although you might need to proof-of-concept on a slightly different F7 model.

http://www.st.com/en/evaluation-tools/stm32756g-eval.html

 

[Tesla DeLorean]

Posted on January 16, 2017 at 21:59

The WaveShare stuff is available via eBay

http://www.ebay.com/itm/Open746I-B-STM32F746IGT6-MCU-ARM-Cortex-M7-Board-7-inch-Touch-LCD-15-Modules-/272145217406?hash=item3f5d1e777e:g:~GsAAOSwuAVWzosl

 

They are likely to be responsive there, and should have 7 and 10' screen options.

[T J]

Posted on January 17, 2017 at 00:47

what size are you after ?

I have made a board with SPI input, or 8 bit parallel 60MHz interface.

I have made another board with a 16 bit parallel interface.

both boards will run upto a 18.5' panel.

however, the drivers are immature since I am a beginner in C.

I have initialised, set a 1366x768 24bit fading background, I drew a line and some text and stopped.

The project is on hold until I get used to writing streams.

but I am open to suggestion.

The SPI board has the panel power switch included. and the CCFL 6pin dimmer connector.

the board is setup for 8M/16M/32MBytes SDRAM

[ray23]

Posted on January 17, 2017 at 18:14

I actually have 2 disco boards, one is for a sound room controller and I want a 5 or 7 inch lcd panel with something on the order of 1024x768.  If I couldn't find this board I was going to default to a 800x480 board which I think I can find.  I am a software guy so the hardware is more difficult for me.

The other board was for my electric brewery and have almost given up on finding something to use.  a 1366x768 resolution on a 12 inch panel would be fine. 

I would be willing to do some of the stream programming it that would help.  Do you have circuit boards for the projects? 

[T J]

Posted on January 17, 2017 at 22:03

Hi, Yes, I have made one board and it works,

then I found I needed extra connectors and the power switch,

The new board is here but not populated.

it is based on the RA8877 Graphics processor, off loading all the video refreshing from your processor.

[ray23]

Posted on January 18, 2017 at 04:00

Are you willing to share somehow?

You can build a board and sell it to me,  if you have a pcb, you can sell that to me, if you have the files to build a board, you can sell that to me?  Or I can contribute to the software for a trade.  I have been in the software business for 30+ years, although I am still learning this stm32f746 board.

[Matej Zub?i?]

Posted on January 19, 2017 at 15:22

Hi,

there are a few approaches that you can take.1. Find a display panel that has matching pins to the ones found on the back side of the Discovery board.Since I'm also interested in finding such panels, I gave a look. The best thing that we could do here is a 5' panel (800x480), but with a mismatch of capacitive touch controller pins. To make that to work, one would have to build an adapter PCB. If such PCB is to be made, then other display panels could also be adopted, e.g. 7' or 10.1' of 1024x600 max. res. Take a look at the following Web page to see more details.

http://developer.toradex.com/knowledge-base/generic-rgb-display-adapter-board

The biggest problem here is that majority of higher resolution panels use either LVDS or MIPI interface. You can search at panelook.com to see what is available. STM32F7X9 does support MIPI-DSI, but only two data lanes.2. Adopt a different discovery board that supports MIPI-DSI and use a DSI to HDMI bridge.You could buy

http://www.st.com/en/evaluation-tools/32f769idiscovery.html

separately without LCD and buy the

http://www.st.com/en/development-tools/b-lcdad-hdmi1.html

adapter. This would allow you to have far more possibilities, i.e. any monitor with the HDMI In port. If you already have some sexy panels laying around. You can order adapter boards from China to drive different panels (LVDS, MIPI or RGB). These adapters provide video-in capability through HDMI, DVI and VGA. Here are some examples of what you might end up with. Search for these numbers at Aliexpress.com:32314647847 - 7' 1024x600 (50pin LVDS) ~30$32763016493 - 7' 1024x600 (40pin LVDS) ~35$32787013313 - 8' 1024x768 ~40$32344321657 - 10.1' 1280x800 ~40$32708439010 - 15.6' 1920x1080 ~50$

If touch screen is needed, then perhaps display panels for Raspberry Pi could be used, albeit, they are rather expensive.

From

http://www.waveshare.com/product/modules/oleds-lcds/raspberry-pi-lcd.htm?dir=asc&order=price

:

7' 1024x600 with capacitive TS ~60$

http://www.waveshare.com/product/modules/oleds-lcds/raspberry-pi-lcd/7inch-hdmi-lcd-c.htm?___SID=U

10.1' 1024x600 with capacitive TS ~100$

http://www.waveshare.com/product/modules/oleds-lcds/raspberry-pi-lcd/10.1inch-hdmi-lcd-with-case.htm?___SID=U

3. Change from STM32F746 to STM32F769 on your discovery board.I might take this approach, since DSI signals are available on the existing display pins if I change the main uC. There would be a need to build an adapter board. But, I would be able to have both DSI (display) and DCMI (camera) interfaces. I hope that with the STM32H7 series they make a discovery board with both DSI and DCMI.

4. Adapter for Raspberry Pi LCD

Use adapter

http://www.st.com/content/st_com/en/products/development-tools/hardware-development-tools/development-tool-hardware-for-mcus/accessories-for-mcu-development-tools/accessories-for-stm32-development-tools/b-lcdad-rpi1.html

 to allow for connection with the official Raspberry Pi LCD. It is a 7' 800x480 display with capacitive touch screen. Price is around 60$.I hope this helps a bit EDIT: Added information about HDMI display panels with touch screen support (in 2. option).Added option 4.