Hello!
I want to use a 5 inch 800x480 TFT display (touch not needed) with an Arduino Uno (or mega if it is a must). I'm thinking of buying this display: link. How can I connect this ?
Do anyone have any advice for displays to order and/or shields for Arduino ? (Preferably a solution that I can reproduce by my self later for mass-production.)
Thanks in advance!
How can I connect this?
You can't. It's just the raw LCD, less the graphics processor. You need one of the pricier boards, one like this:
Trying to drive an 800x480 display with an Uno/Mega is not practical, you really need a Due or better to achieve reasonable screen update rates.
Edit: The link you provided has a trailing period at the end that should be removed, it results in a 404 error. Also changed my link to a recommended display, it was not an 800x480 display.
avr_fred:
You can't. It's just the raw LCD, less the graphics processor. You need one of the pricier boards, one like this:http://www.buydisplay.com/default/tft-5-inch-lcd-display-module-controller-board-serial-i2c-ra8875
Trying to drive an 800x480 display with an Uno/Mega is not practical, you really need a Due or better to achieve reasonable screen update rates.
Edit: The link you provided has a trailing period at the end that should be removed, it results in a 404 error. Also changed my link to a recommended display, it was not an 800x480 display.
Okay thanks for the advice about using a due. Then how can I connect the Controller Board Serial I2C to the Due? Do I need a shield or can it be achievable in some other way ?
Thank you!
I2C is okay for a character based LCD but it is waaayyy too slow to drive a TFT, it's by far the worst choice, even with the 400khz high speed version. SPI is a reasonable choice if I/O pins are in short supply, SPI with DMA is even better.
A display shield is the fastest and easiest way to get a TFT LCD up and running on an Arduino. There is an undefined "standard" for this, ultilizing a 20x2 header pin connection to the LCD, a typical example:
The graphics drivers are on the LCD board, common types are the SSD1963 and RA8875. Buydisplay sells both driver types with the standard 20x2 connector and shields as well. It's probably worth a mention that there are far more driver choices in smaller displays but when you get to the higher pixel counts, the field narrows rapidly.
Parallel I/O, 16 bits wide, is usually the fastest way to drive a screen but the Due presents a conundrum in that regard as the designers mapped the physical ports to the digital pins rather poorly, the result being you have to bit twiddle and write to multiple hardware ports to achieve parallel I/O, thereby decreasing the overall efficiency. This is really not a concern if you're using an exsisting library, only if you're writing your own code but I mention this as you said you would be making your own board - and so you could address this deficiency.
Ok thanks for the explanation. I will buy the display kit with the controller board and RA8875 shield from buydisplay.com with a Due. But I came across the similar RA8875 driver from Adafruit, which provides the PCB Eagle files that I can use later. Can I use that one as well as the RA8875 shield from buydisplay.com or is something different?
Or can I even use the raw display with the Adafruit RA8875 driver ?
Thanks again
Or can I even use the raw display with the Adafruit RA8875 driver ?
You should be able to do that. That said, you can also buy the 800x480 LCD directly from Adafruit and you'd have their support to get things running. While it's certainly more money, it's light years faster delivery and you'd have a real warranty versus a warranty that would require you to return the LCD to China for replacement. Just my 0.02 cents.
The only difference I see see is that the Adafruit implementation supports the SPI interface only. The Buydisplay version of the RA8875 supports both parallel and SPI versions. That's a decision you need to make at some point - but you'd need to test both in order to know which one is faster. Ultimately, I don't know if speed versus I/O count matters to you.