Make all the connections as in the previous part of the schematic. Download the code and libraries ferom below. To install the library, download the .zip file below, open Arduino IDE and go to Sketch, include library, add .zip library and open the .zip file that you have just downloaded. Now the ST7735 and Adafruit GFX library sould be installed. Open the print bmp code. Compile and check for errors and uplaod it to the Arduino NANO. Make sure you copy some bmp files to the card with the 160 by 128 pixels resolution. You can download it from the tutorial page here. In the code you can change the
#include <Adafruit_GFX.h> // Core graphics library
#include <Adafruit_ST7735.h> // Hardware-specific library for ST7735
#include <SPI.h>
#include <SD.h>
#define TFT_RST 7 // Reset line for TFT (or see below...)
#define TFT_CS 6 // Chip select line for TFT display
#define TFT_DC 5 // Data/command line for TFT
#define SD_CS 2 // Chip select line for SD card
//D11 -> MOSI SD + SDA TFT
//D12 -> MISO SD
//D13 -> SCK SD + SCL TFT
// For 0.96", 1.44" and 1.8" TFT with ST7735 use
Adafruit_ST7735 tft = Adafruit_ST7735(TFT_CS, TFT_DC, TFT_RST);
// For 1.54" TFT with ST7789
//Adafruit_ST7789 tft = Adafruit_ST7789(TFT_CS, TFT_DC, TFT_RST);
void setup(void) {
Serial.begin(9600);
while (!Serial) {
delay(10); // wait for serial console
}
pinMode(TFT_CS, OUTPUT);
digitalWrite(TFT_CS, HIGH);
pinMode(SD_CS, OUTPUT);
digitalWrite(SD_CS, HIGH);
// Use this initializer if you're using a 1.8" TFT
tft.initR(INITR_BLACKTAB);
// Use this initializer (uncomment) if you're using a 1.44" TFT
//tft.initR(INITR_144GREENTAB);
// Use this initializer (uncomment) if you're using a 0.96" 180x60 TFT
//tft.initR(INITR_MINI160x80); // initialize a ST7735S chip, mini display
// Use this initializer (uncomment) if you're using a 1.54" 240x240 TFT
//tft.init(240, 240); // initialize a ST7789 chip, 240x240 pixels
tft.fillScreen(ST77XX_BLACK);
Serial.print("Initializing SD card...");
if (!SD.begin(SD_CS)) {
Serial.println("failed!");
return;
}
Serial.println("OK!");
File root = SD.open("/");
printDirectory(root, 0);
root.close();
// change the name here!
bmpDraw("1.BMP", 0, 0);
// wait 5 seconds
delay(5000);
}
void loop() {
// uncomment these lines to draw bitmaps in different locations/rotations!
/*
tft.fillScreen(ST7735_BLACK); // Clear display
for(uint8_t i=0; i<4; i++) // Draw 4 parrots
bmpDraw("parrot.bmp", tft.width() / 4 * i, tft.height() / 4 * i);
delay(1000);
tft.setRotation(tft.getRotation() + 1); // Inc rotation 90 degrees
*/
}
// This function opens a Windows Bitmap (BMP) file and
// displays it at the given coordinates. It's sped up
// by reading many pixels worth of data at a time
// (rather than pixel by pixel). Increasing the buffer
// size takes more of the Arduino's precious RAM but
// makes loading a little faster. 20 pixels seems a
// good balance.
#define BUFFPIXEL 20
void bmpDraw(char *filename, uint8_t x, uint16_t y) {
File bmpFile;
int bmpWidth, bmpHeight; // W+H in pixels
uint8_t bmpDepth; // Bit depth (currently must be 24)
uint32_t bmpImageoffset; // Start of image data in file
uint32_t rowSize; // Not always = bmpWidth; may have padding
uint8_t sdbuffer[3*BUFFPIXEL]; // pixel buffer (R+G+B per pixel)
uint8_t buffidx = sizeof(sdbuffer); // Current position in sdbuffer
boolean goodBmp = false; // Set to true on valid header parse
boolean flip = true; // BMP is stored bottom-to-top
int w, h, row, col;
uint8_t r, g, b;
uint32_t pos = 0, startTime = millis();
if((x >= tft.width()) || (y >= tft.height())) return;
Serial.println();
Serial.print(F("Loading image '"));
Serial.print(filename);
Serial.println('\'');
// Open requested file on SD card
if ((bmpFile = SD.open(filename)) == NULL) {
Serial.print(F("File not found"));
return;
}
// Parse BMP header
if(read16(bmpFile) == 0x4D42) { // BMP signature
Serial.print(F("File size: ")); Serial.println(read32(bmpFile));
(void)read32(bmpFile); // Read & ignore creator bytes
bmpImageoffset = read32(bmpFile); // Start of image data
Serial.print(F("Image Offset: ")); Serial.println(bmpImageoffset, DEC);
// Read DIB header
Serial.print(F("Header size: ")); Serial.println(read32(bmpFile));
bmpWidth = read32(bmpFile);
bmpHeight = read32(bmpFile);
if(read16(bmpFile) == 1) { // # planes -- must be '1'
bmpDepth = read16(bmpFile); // bits per pixel
Serial.print(F("Bit Depth: ")); Serial.println(bmpDepth);
if((bmpDepth == 24) && (read32(bmpFile) == 0)) { // 0 = uncompressed
goodBmp = true; // Supported BMP format -- proceed!
Serial.print(F("Image size: "));
Serial.print(bmpWidth);
Serial.print('x');
Serial.println(bmpHeight);
// BMP rows are padded (if needed) to 4-byte boundary
rowSize = (bmpWidth * 3 + 3) & ~3;
// If bmpHeight is negative, image is in top-down order.
// This is not canon but has been observed in the wild.
if(bmpHeight < 0) {
bmpHeight = -bmpHeight;
flip = false;
}
// Crop area to be loaded
w = bmpWidth;
h = bmpHeight;
if((x+w-1) >= tft.width()) w = tft.width() - x;
if((y+h-1) >= tft.height()) h = tft.height() - y;
// Set TFT address window to clipped image bounds
tft.setAddrWindow(x, y, x+w-1, y+h-1);
for (row=0; row<h; row++) { // For each scanline...
// Seek to start of scan line. It might seem labor-
// intensive to be doing this on every line, but this
// method covers a lot of gritty details like cropping
// and scanline padding. Also, the seek only takes
// place if the file position actually needs to change
// (avoids a lot of cluster math in SD library).
if(flip) // Bitmap is stored bottom-to-top order (normal BMP)
pos = bmpImageoffset + (bmpHeight - 1 - row) * rowSize;
else // Bitmap is stored top-to-bottom
pos = bmpImageoffset + row * rowSize;
if(bmpFile.position() != pos) { // Need seek?
bmpFile.seek(pos);
buffidx = sizeof(sdbuffer); // Force buffer reload
}
for (col=0; col<w; col++) { // For each pixel...
// Time to read more pixel data?
if (buffidx >= sizeof(sdbuffer)) { // Indeed
bmpFile.read(sdbuffer, sizeof(sdbuffer));
buffidx = 0; // Set index to beginning
}
// Convert pixel from BMP to TFT format, push to display
b = sdbuffer[buffidx++];
g = sdbuffer[buffidx++];
r = sdbuffer[buffidx++];
tft.pushColor(tft.color565(r,g,b));
} // end pixel
} // end scanline
Serial.print(F("Loaded in "));
Serial.print(millis() - startTime);
Serial.println(" ms");
} // end goodBmp
}
}
bmpFile.close();
if(!goodBmp) Serial.println(F("BMP format not recognized."));
}
// These read 16- and 32-bit types from the SD card file.
// BMP data is stored little-endian, Arduino is little-endian too.
// May need to reverse subscript order if porting elsewhere.
uint16_t read16(File f) {
uint16_t result;
((uint8_t *)&result)[0] = f.read(); // LSB
((uint8_t *)&result)[1] = f.read(); // MSB
return result;
}
uint32_t read32(File f) {
uint32_t result;
((uint8_t *)&result)[0] = f.read(); // LSB
((uint8_t *)&result)[1] = f.read();
((uint8_t *)&result)[2] = f.read();
((uint8_t *)&result)[3] = f.read(); // MSB
return result;
}
void printDirectory(File dir, int numTabs) {
while (true) {
File entry = dir.openNextFile();
if (! entry) {
// no more files
break;
}
for (uint8_t i = 0; i < numTabs; i++) {
Serial.print('\t');
}
Serial.print(entry.name());
if (entry.isDirectory()) {
Serial.println("/");
printDirectory(entry, numTabs + 1);
} else {
// files have sizes, directories do not
Serial.print("\t\t");
Serial.println(entry.size(), DEC);
}
entry.close();
}
}