Friday, January 30, 2015

Hacking the 1.44" TFT LCD for my Smart Watch Project

I have several stocks of these cute lcd's and for months they've been there neglected. And then one day, I came up with an idea of why not make my own smartwatch by using this lcd, it rung a bell on my head and yeah, why not, it is quite an exciting project. There are so many uses of small lcd aside from making them as watches or pendants. This one cool project at the Discovery Wall at Weill Cornell Medical College is just one of them.

(Credits to the owner)

So I begun to dig into it to find more information about this tft lcd. And here is what I have found out:
1. The tiny lcd is being driven by ILI9163 chip and several arduino users have created libraries so that it will be a lot easier for others to use this lcd. I am not very good at creating my own library so this is an advantage of being an arduino fan, things can be so easy. And yep it is really easy, here is my first round of testing:

So now that I was able to make it work, I need to dig deeper to get more information, My project is a smartwatch so I need to keep it as thin as possible and the red pcb where the lcd was attached is quite thick so I will have to remove the lcd from it without harming it. The lcd has very few external components so getting rid of the pcb will not be a big problem. Here's the progress of my work:

And like I said, the circuitry is very simple so all I have to do is copy the schematic diagram in KiCAD so that I can integrate it easily with other modules. Here's the schematic diagram:

As I was checking further, I realized that the Arduino running at 16Mhz can really be very slow so I thought of using the teensy 3.1 which runs at 72Mhz. And another user has published his code that runs the adafruit library on the teensy 3.1. This did not only copy the adafruit library, he optimized it and the result is a super fast graphics library.

Here is the video of the optimized library in action: