blue pill - st7735s tft display for sale
Got three of them all working(1 with Arduino Leonardo and 2 with NodeMCU ESP8266).arduino will need a solution to the 5v out 3.3v in(10s solder job) NodeMCU is directly compatible.i used adafruits code.Very happy. getting more. also hiletgo products have all been functional so far. becoming a fan.Update: switched to TFT_eSPI.h library. Wow. Orders of magnitude faster display now. A bit trickier to setup but well worth it.
C: \Users\guido\AppData\Local\Temp\arduino_modified_sketch_390395\graphicstest.ino: 123: 397: warning: deprecated conversion from string constant to "char*" [-Wwrite - strings]
C: \Users\guido\OneDrive\Arduino Save Location\libraries\Adafruit_BusIO\Adafruit_I2CDevice.cpp: 88: 47: error: invalid conversion from "const uint8_t* {aka const unsigned char*}" to "uint8* {aka unsigned char*}" [-fpermissive]
C: \Users\guido\AppData\Local\Arduino15\packages\stm32duino\hardware\STM32F1\2021.3.18\libraries\Wire / utility / WireBase.h: 123: 12: error: initializing argument 1 of "size_t WireBase::write(uint8*, int)" [-fpermissive]
C: \Users\guido\OneDrive\Arduino Save Location\libraries\Adafruit_BusIO\Adafruit_I2CDevice.cpp: 97: 31: error: invalid conversion from "const uint8_t* {aka const unsigned char*}" to "uint8* {aka unsigned char*}" [-fpermissive]
C: \Users\guido\AppData\Local\Arduino15\packages\stm32duino\hardware\STM32F1\2021.3.18\libraries\Wire / utility / WireBase.h: 123: 12: error: initializing argument 1 of "size_t WireBase::write(uint8*, int)" [-fpermissive]
The display is driven by a ST7735R controller ( ST7735R-specifications.pdf (2.1 MB) ), can be used in a “slow” and a “fast” write mode, and is 3.3V/5V compatible.
Adafruit_ST7735 is the library we need to pair with the graphics library for hardware specific functions of the ST7735 TFT Display/SD-Card controller.
Basically, besides the obvious backlight, we tell the controller first what we are talking to with the CS pins. CS(TFT) selects data to be for the Display, and CS(SD) to set data for the SD-Card. Data is written to the selected device through SDA (display) or MOSI (SD-Card). Data is read from the SD-Card through MISO.
So when using both display and SD-Card, and utilizing the Adafruit libraries with a SainSmart display, you will need to connect SDA to MOSI, and SCL to SCLK.
As mentioned before, the display has a SLOW and a FAST mode, each serving it’s own purpose. Do some experiments with both speeds to determine which one works for your application. Of course, the need of particular Arduino pins plays a role in this decision as well …
Note: Adafruit displays can have different colored tabs on the transparent label on your display. You might need to adapt your code if your display shows a little odd shift. I noticed that my SainSmart display (gree tab) behaves best with the code for the black tab – try them out to see which one works best for yours.
Low Speed display is about 1/5 of the speed of High Speed display, which makes it only suitable for particular purposes, but at least the SPI pins of the Arduino are available.
After connecting the display in Low Speed configuration, you can load the first example from the Arduino Software (“File” “Example” “Adafruit_ST7735” – recommend starting with the “graphictest“).
Below the code parts for a LOW SPEED display (pay attention to the highlighted lines) – keep in mind that the names of the pins in the code are based on the Adafruit display:
The SD-Card needs to be FAT-16 or FAT-32 formatted, single partition, and the BMP file needs to be placed in the root (ie. not in a directory or anything like that).
You can name your BMP file “parrot.bmp” or modify the Sketch to have the proper filename (in “spitftbitmap” line 70, and in “soft_spitftbitmap” line 74).
#define SD_CS 4 // Chip select line for SD card#define TFT_CS 10 // Chip select line for TFT display#define TFT_DC 9 // Data/command line for TFT#define TFT_RST 8 // Reset line for TFT (or connect to +5V)
#define SD_CS 4 // Chip select line for SD card#define TFT_CS 10 // Chip select line for TFT display#define TFT_DC 9 // Data/command line for TFT#define TFT_RST 8 // Reset line for TFT (or connect to +5V)
To use this in your Arduino Sketch: The first 2 characters represent RED, the second set of two characters is for GREEN and the last 2 characters represent BLUE. Add ‘0x’ in front of each of these hex values when using them (‘0x’ designates a hexadecimal value).
This function is used to indicate what corner of your display is considered (0,0), which in essence rotates the coordinate system 0, 90, 180 or 270 degrees.
However, if your application needs your screen sideways, then you’d want to rotate the screen 90 degrees, effectively changing the display from a 128×160 pixel (WxH) screen to a 160×128 pixel display. Valid values are: 0 (0 degrees), 1 (90 degrees), 2 (180 degrees) and 3 (270 degrees).
tft.print("Lorem ipsum dolor sit amet, consectetur adipiscing elit. Curabitur adipiscing ante sed nibh tincidunt feugiat. Maecenas enim massa, fringilla sed malesuada et, malesuada sit amet turpis. Sed porttitor neque ut ante pretium vitae malesuada nunc bibendum. Nullam aliquet ultrices massa eu hendrerit. Ut sed nisi lorem. In vestibulum purus a tortor imperdiet posuere. ");