Pins of a 3.5 inch TFT screen? - Page 1
Forum section: electronics / beginners

author: Vincenzo
author_rank: Regular Contributor
timestamp: May 29, 2021, 02:33:20 pm
content: I bought this screen recently and it comes with a little plastic stylus because it is a touch screen in addition to having a microSD slot. It was about US $12 from ebay and it worked when I used an arduino with a couple of libraries to test (Fruit GFX, and MCUFriend, I think their names).The two chips shown on the back side are onlu '245 octal buffer/driver chips.The SD pins are obvious because they start with SD.Which pins are the touch functionality pins?Any info about those screens are appreciated because it is rare by simply googling.

author: MasterT
author_rank: Frequent Contributor
timestamp: May 29, 2021, 03:32:40 pm
content: Quotehttps://create.arduino.cc/projecthub/electropeak/arduino-2-4-touch-screen-lcd-shield-tutorial-fe6f05You can use your multimeter to test resistance among those pins. Sometimes its varying.

author: Vincenzo
author_rank: Regular Contributor
timestamp: May 29, 2021, 04:20:08 pm
content: Thanks much. I don't know how I missed this. The only difference is the size. Didn't understand the quote but there is a table that has different shades of blue that gives me exactly what i was looking for. Is there a little module on ebay that connects to those screens and make them I2C or SPI serial?

author: MasterT
author_rank: Frequent Contributor
timestamp: May 29, 2021, 04:36:01 pm
content: Nothing I aware of. There are shields ST7735 ST7789 with spi interface. I2C isn't an option - too slow.You may get arduino uno regular fashion, aliexpress price $-3-4 and use it as spi to parallel interface. Arduino would communicate over D10-D13 - free w/o SD card attached spi pins to master cpu..

author: WattsThat
author_rank: Frequent Contributor
timestamp: May 29, 2021, 07:23:32 pm
content: QuoteNo such board. I2C is okay for character mode LCDs but not graphics.Native SPI screens are commonly available with the ST7735 controller at 1.8/2.2/2.4 inches at a 132x162 maximum resolution. The larger 2.2/2.4/2.8/3.2 inch sizes at 240x320 resolution have the ILI9341 controller.Once above 240x320 resolution, it’s anybody’s guess on the controller which determines how easy it would be to find a usable library with reasonable performance.It is fair to say that once past the physical board specs, there is little to no standardization in the market segment known as cheap Arduino plug-in tft’s.

author: Vincenzo
author_rank: Regular Contributor
timestamp: May 30, 2021, 02:38:02 am
content: I, actually, lost track of "Arduino" and "Uno" and other italian (or italianized english) words used for renaming Atmel (and now other) chips after adding a piece of assembly in them, I use the Atmel chips themselves. It was cute over 15 years ago when the idea was new, and always cute for microcontroller beginners for a few experiments. Another thing, I don't like those professional C++ programmers who engrave "Ardino pin numbers" in stone in their classes/libraries and the daughter boards in the shape of the 2005 original board (to save those programmers from the savagery of using physical tools like a soldering iron or the EE SW tools like PCB design), so I always add to my notebook lookup tables and notes for flexibility after spending quite a bit of time inside their code files looking for the "stones". I believe, like most people I know, that your own personal "Arduino"/project board is a PCB order away.

author: coromonadalix
author_rank: Super Contributor
timestamp: May 31, 2021, 02:48:08 am
content: Theses ones came uphttps://forum.arduino.cc/t/3-5-tft-lcd-from-mcufriend-for-arduino-uno-320x480-ili9327/339132https://forum.arduino.cc/t/help-mcufriend-3-5-tft-lcd-480x320-esp32-solved/559854try this one firsthttps://iotexpert.com/mcu-friend-3-5-tft-identification/

author: Vincenzo
author_rank: Regular Contributor
timestamp: May 31, 2021, 10:21:30 am
content: Quote from: coromonadalix on May 31, 2021, 02:48:08 amThese are GREATThis screen makes a great major part for any project for its price. And to make life easier a small Atmel microcontroller can be used with it simply as a HMI or GUI with the "Arduino as ISP" those "libraries" for a couple of bucks.Thnx much