TFT technology might be ancient news for monitors and TVs, but it’s alive and well when it comes to hobbyist electronics and embedded devices. They’ve now become even easier to integrate, thanks to the Universal TFT Display Backpack design by [David Johnson-Davies].
![](https://hackaday.com/wp-content/uploads/2022/06/tftbackpack-small.jpg?w=400)
Such displays are affordable and easy to obtain, and [David] noticed that many seemed to have a lot in common when it came to pinouts and hookup info. The result is his breakout board design, a small and easy-to-assemble PCB breakout board that can accommodate the pinouts of a wide variety of TFT displays available from your favorite retailers or overseas sellers.
The board has a few quality-of-life features such as an optional connection for a backlight, and a staggered pin pattern so that different TFT boards can be pushed in to make a solid connection without soldering. That’s very handy for testing and evaluating different displays.
Interested? Head on over to the GitHub repository for the project, and while you’re at it, check out [David]’s Tiny TFT Graphics Library 2 which is a natural complement to the display backpack. [David] sure knows his stuff when it comes to cleverly optimized display work; we loved his solution for writing to OLED displays without needing a RAM buffer.
I had no idea that interface boards er driver boards er riser cards er piggyback boards er daughter boards were called ‘backpacks’ these days. Nice project.
Think it’s an Adafruit coined term. They used it a while back for their 7 segment displays that had a driver IC on the back so you could just talk to them via I2C instead of multiplexing the digits.
Nope. It predates that. The first one was the LCD backpack, from Scott Edwards Electronics. Ideal for use with the Basic Stamp.
Of course, this being the internet, some wag will come along and tell me I’m wrong. Except I’m not, naturally.
I recall some use of the term for rear expansion connector peripherals on 8 bit microcomputers. Hence why Microsolutions used the term for their parallel port drive interfaces from the early 90s. Backpack CD/HDD/Floppy drives.
Yes, but that has nothing to do with displays. Thanks for playing.
There was a product for the Radio Shack Model 100 that fitted on the back, or replaced the back cover, and provided room for ROMs and other accessories. I think that was called a “backpack”, but it’s been decades
That also has nothing to do with displays.
I dont think it has to be in reference to a display, I thought it was just another term for a kind of near universal daughterboard that performs some function in the same vein as things being called hats. But hats were specifically PI related hardware. I clearly could be wrong, not naturally as stated above. (You must know how that makes you look right?)
When I was a kid I had this satchel with straps that would carry books and various learning utensils. I would strap this “pack” onto my “back” and it made carrying these things much easier.
We were talking in the context of displays.
Unless you carried your Nipkow Disk in your “back pack” I suppose.
i’m dreaming about svg or pdf screen
a long time ago i use a x11 server on solaris with postscript , ideal scale, very fast
I am not sure why move from based SPI to I2C?
The ‘Tiny TFT Graphics Library 2 ‘ page linked to above explains that. If TL;DR – it’s the pinouts.
Because it is easier to add multiple devices. With SPI you need a pin (chip enable) per device. But, with I2C you don’t. SPI is a very simple interface – you can bit bang it or even use shift registers. SPI is potentially a lot faster.
I2C has the advantage of a 4-wire interface no matter how many devices. SPI needs a separate select line for each device on the bus. Disadvantage is that I2C is much slower than SPI.
It’s probably still slower than SPI, but there is some “high-speed-I2C”-mode with push-pull outputs that was introduced some time ago. No idea if there is any IC supporting it and i don’t remember the details, but it should be in the public specifications.