The problem that I am having is trying to run a demo code for displaying .bmp image 24bit on tftTouch shield from sdshield
when i run the demo code all i get is a scattered bit of mess of pixels on the screen.
code is as follows :
// This sketch is adapted to Seeed's TFT library from
// https://github.com/adafruit/TFTLCD-Library/blob/master/examples/tftbmp/tftbmp.pde
// by ladyada/adafruit under MIT license
#include <SD.h>
#include <TFT.h>
#include <SPI.h>
// In the SD card, place 24 bit color BMP files (be sure they are 24-bit!)
// the file itself
File bmpFile;
// information we extract about the bitmap file
int bmpWidth, bmpHeight;
uint8_t bmpDepth, bmpImageoffset;
void setup()
{
Serial.begin(9600);
Tft.init();
Serial.print("Initializing SD card...");
pinMode(10, OUTPUT); //53 is used as chip select pin
if (!SD.begin(10)) { //53 is used as chip select pin
Serial.println("failed!");
return;
}
Serial.println("SD OK!");
}
void loop()
{
Tft.setOrientation(0);
//Image 1
bmpFile = SD.open("test.bmp");
if (! bmpFile) {
Serial.println("didnt find image");
while (1);
}
if (! bmpReadHeader(bmpFile)) {
Serial.println("bad bmp");
return;
}
Serial.print("image size ");
Serial.print(bmpWidth, DEC);
Serial.print(", ");
Serial.println(bmpHeight, DEC);
bmpdraw(bmpFile, 0, 0);
delay(3000);
bmpFile.close();
//Image 2
bmpFile = SD.open("test1.bmp");
if (! bmpFile) {
Serial.println("didnt find image");
while (1);
}
if (! bmpReadHeader(bmpFile)) {
Serial.println("bad bmp");
return;
}
Serial.print("image size ");
Serial.print(bmpWidth, DEC);
Serial.print(", ");
Serial.println(bmpHeight, DEC);
bmpdraw(bmpFile, 0, 0);
delay(3000);
}
/*********************************************/
// This procedure reads a bitmap and draws it to the screen
// its sped up by reading many pixels worth of data at a time
// instead of just one pixel at a time. increading the buffer takes
// more RAM but makes the drawing a little faster. 20 pixels' worth
// is probably a good place
#define BUFFPIXEL 20
void bmpdraw(File f, int x, int y) {
bmpFile.seek(bmpImageoffset);
uint32_t time = millis();
uint16_t p;
uint8_t g, b;
int i, j;
uint8_t sdbuffer[3 * BUFFPIXEL]; // 3 * pixels to buffer
uint8_t buffidx = 3*BUFFPIXEL;
for (i=0; i< bmpHeight; i++) {
Tft.setXY(x, y+bmpHeight-i);
for (j=0; j<bmpWidth; j++) {
// read more pixels
if (buffidx >= 3*BUFFPIXEL) {
bmpFile.read(sdbuffer, 3*BUFFPIXEL);
buffidx = 0;
}
// convert pixel from 888 to 565
b = sdbuffer[buffidx++]; // blue
g = sdbuffer[buffidx++]; // green
p = sdbuffer[buffidx++]; // red
p >>= 3;
p <<= 6;
g >>= 2;
p |= g;
p <<= 5;
b >>= 3;
p |= b;
// write out the 16 bits of color
Tft.sendData(p);
}
}
Serial.print(millis() - time, DEC);
Serial.println(" ms");
}
boolean bmpReadHeader(File f) {
// read header
uint32_t tmp;
if (read16(f) != 0x4D42) {
// magic bytes missing
return false;
}
// read file size
tmp = read32(f);
Serial.print("size 0x"); Serial.println(tmp, HEX);
// read and ignore creator bytes
read32(f);
bmpImageoffset = read32(f);
Serial.print("offset "); Serial.println(bmpImageoffset, DEC);
Serial.print(f);
// read DIB header
tmp = read32(f);
Serial.print("header size "); Serial.println(tmp, DEC);
bmpWidth = read32(f);
bmpHeight = read32(f);
if (read16(f) != 1)
return false;
bmpDepth = read16(f);
Serial.print("bitdepth "); Serial.println(bmpDepth, DEC);
if (read32(f) != 0) {
// compression not supported!
return false;
}
Serial.print("compression "); Serial.println(tmp, DEC);
return true;
}
/*********************************************/
// These read data from the SD card file and convert them to big endian
// (the data is stored in little endian format!)
// LITTLE ENDIAN!
uint16_t read16(File f) {
uint16_t d;
uint8_t b;
b = f.read();
d = f.read();
d <<= 8;
d |= b;
return d;
}
// LITTLE ENDIAN!
uint32_t read32(File f) {
uint32_t d;
uint16_t b;
b = read16(f);
d = read16(f);
d <<= 16;
d |= b;
return d;
}
Then the serial output that i get while running this sketch is:
Initializing SD card...SD OK!
size 0x38438
offset 54
1header size 40
bitdepth 24
compression 40
image size 240, 320
if anyone can help me sort this out it would be greatly appreciated.