Some time ago I bought a couple of the cheap Chinese DSO138 oscilloscope kits. I bought these as I was just getting into electronics and thought they would be useful/good to practice on.
A few year on and I don't use the oscilloscopes but would like to re-use the detachable 2.4" TFT LCD screens which they came with. The displays each have 2 sets of identical 40 pins, one set at the side and the other at the top. I hope these can be seen on the photos.
The question is, can these be used with an Arduino Uno and, if so, how do I connect it? Also, what library/libraries would I need and are there any example codes I could try?
From the research I've done the pinout of the displays is as follows.
It seems that the LCD's are based on the ILI9341, as many of the Adafruit ones are, however, they seem to use SPI or I2C to connect rather than 40 pins.
I appreciate that the UNO's 3.3v current capacity is limited and there will have to be some level shifting done, but it seems a waste not to use these salvaged LCD's. I am, however, happy to be told that it would be too much trouble and I'd be better off buying a new display.
Certainly they can be used with an Arduino Uno. You'll likely need I/O expanders, shift registers or latches to handle the 16 bit data bus, but it's doable. As to exactly how you connect it... that's up to you. I suggest a long sit down with the DSO138 schematic as a start. And breadboards. Lots of breadboards. And the controller's datasheet.
I honestly don't understand why people have this persistent idea that there's a preexisting library for every random bit of kit out there. Sometimes you just have to start from scratch. In this case you're fortunate in that I'm fairly sure that I've seen code at some point (whether it was 3rd party or official, I don't remember) that will run the DSO138, so if you can find that you've got a starting point. But if you're expecting to find a library that you can just plug in, load up an example and have the display work... toss 'em and buy something that someone's already done all the hard work for you. This display definitely falls in the "an interesting challenge that you'll spend a lot of time puzzling over before you get it working" category.
