Arduino Forum

Using Arduino => Displays => Topic started by: Venoox on Dec 18, 2018, 10:23 pm

Title: 1,8" TFT ST7735 Display
Post by: Venoox on Dec 18, 2018, 10:23 pm
Hello, I managed to get my display working with Adafruit GFX and Adafruit ST7735 library. I did a graphicstest example and it was ok for the most part but it was a little weird and I don't know if that's normal, for better explanation here's a video: https://youtu.be/Q1bgz6n1ZAs (https://youtu.be/Q1bgz6n1ZAs)
GND and LED- are wired to ground. LED+ is wired to 5v. VCC is wired to 3.3v.

(https://i.imgur.com/WfIrUxv.jpg)
Title: Re: 1,8" TFT ST7735 Display
Post by: mabo47 on Dec 19, 2018, 09:12 am
Hi,

Do you have datasheet (or at least a link of where you bought it)?

Also, would be nice to post all the pin setup.

Kind regards,
Title: Re: 1,8" TFT ST7735 Display
Post by: david_prentice on Dec 19, 2018, 10:14 am
The display is designed to plug into the 16x2 HD44780 LCD header of an 8051 dev board.

The 3V TFT controller and 3V SD card are bit-bashed by the 5V 8051.
The 8051 does not have push-pull output drivers.   It can only sink current.
This means that the 3V electronics do not get harmed by 5V logic.

Your Arduino Uno has 5V push-pull output.   Both for GPIO and for SPI.
You should really use 3V level shifters (or series resistors).

There are plenty of explanations and tutorials for driving 3V ST7735 displays.
Your Blue display will be the same.    A0, DC, RS are different names for the same thing.    SCL, SCK, SCLK is SPI clock.   SDA, SDI, MOSI is SPI data.

The board has an AMS1117 LDO regulator.   So you can connect VCC to 5V safely.    You can connect LED+ to 5V via a series resistor.

David.
Title: Re: 1,8" TFT ST7735 Display
Post by: Venoox on Dec 19, 2018, 06:44 pm
I connected LED+ through a resistor to 5v and VCC to 5v but nothing changed