Important changes to forums and questions
All forums and questions are now archived. To start a new conversation or read the latest updates go to forums.mbed.com.
11 years ago.
KL25Z SPI format
Is there a problem with the SPI 16 bit format on the KL25Z ? I get flashy red light.
2 Answers
11 years ago.
The SPI controller inside the KL25Z only support 8 bit ! You have to split the transfer into two times 8 bit.
Accepted Answer
poster
11 years ago.
Thank you Peter, I knew it would not be easy.
The library below works fine on the LPC1768 but not on the KL25Z
The important part is the character function:
void ST7735_TFT::character(int x, int y, int c)
Any ideas how to change this to 8 bit mode?
#include "ST7735_TFT.h"
#include "mbed.h"
#define BPP 16 // Bits per pixel
ST7735_TFT::ST7735_TFT(PinName mosi, PinName miso, PinName sclk, PinName cs, PinName rs, PinName reset, const char *name)
: _spi(mosi, miso, sclk), _cs(cs), _rs(rs), _reset(reset),GraphicsDisplay(name)
{
tft_reset();
orientation = 2;
char_x = 0;
}
int ST7735_TFT::width() {
if (orientation == 0 || orientation == 2) return 128;
else return 160;
}
int ST7735_TFT::height() {
if (orientation == 0 || orientation == 2) return 160;
else return 128;
}
void ST7735_TFT::set_orientation(unsigned int o) {
orientation = o;
switch (orientation) {
case 0:
wr_reg(ST7735_MADCTL, 0x0008);
break;
case 1:
wr_reg(ST7735_MADCTL, 0x0068);
break;
case 2:
wr_reg(ST7735_MADCTL, 0x00C8);
break;
case 3:
wr_reg(ST7735_MADCTL, 0x00A8);
break;
}
}
void ST7735_TFT::wr_cmd(int cmd) {
_rs = 0; // rs low, cs low for transmitting command
_cs = 0;
_spi.write(cmd);
_cs = 1;
}
void ST7735_TFT::wr_dat(int dat) {
_rs = 1; // rs high, cs low for transmitting data
_cs = 0;
_spi.write(dat);
_cs = 1;
}
void ST7735_TFT::wr_dat_start(void) {
_rs = 1; // rs high, cs low for transmitting data
_cs = 0;
}
void ST7735_TFT::wr_dat_stop (void) {
_cs = 1;
}
void ST7735_TFT::wr_dat_only (unsigned short dat) {
_spi.write(dat);
}
unsigned short ST7735_TFT::rd_dat (void) {
unsigned short val = 0;
_cs = 0;
_spi.write(0); /* Dummy read 1 */
val = _spi.write(0); /* Read D8..D15 */
val <<= 8;
val |= _spi.write(0); /* Read D0..D7 */
_cs = 1;
return (val);
}
void ST7735_TFT::wr_reg (unsigned char reg, unsigned short val) {
wr_cmd(reg);
wr_dat(val);
}
unsigned short ST7735_TFT::rd_reg (unsigned char reg) {
wr_cmd(reg);
return(rd_dat());
}
void ST7735_TFT::read_area(unsigned int x, unsigned int y, unsigned int w, unsigned int h,unsigned char *buffer) {
// BEWARE !
// DOES NOT WORK CORRECTLY YET !!!
int val;
window(x,y,w,h);
wr_cmd(ST7735_RAMRD); // write to RAM
_cs = 0;
_rs = 1;
_spi.write(0); /* Dummy read 1 */
val = _spi.write(0); /* Read D8..D15 */
val <<= 8;
val |= _spi.write(0); /* Read D0..D7 */
_cs = 1;
}
int ST7735_TFT::getpixel(unsigned int x, unsigned int y) {
// BEWARE !
// DOES NOT WORK CORRECTLY YET !!!
int val;
_spi.format(8,3);
wr_cmd(ST7735_CASET); // column addr set
wr_dat(0x00);
wr_dat(x+2); // XSTART
wr_dat(0x00);
wr_dat(x+2+2); // XEND
wr_cmd(ST7735_RASET); // row addr set
wr_dat(0x00);
wr_dat(y+1); // YSTART
wr_dat(0x00);
wr_dat(y+1+1); // YEND
_rs = 0; // rs low, cs low for transmitting command
_cs = 0;
_spi.write(0x2E);
_rs = 1;
_spi.write(0x00); /* Dummy read 1 */
val = _spi.write(0x00); /* Read D8..D15 */
val <<= 8;
val |= _spi.write(0x00); /* Read D0..D7 */
_cs = 1;
return val;
}
void ST7735_TFT::tft_reset() {
//static unsigned short driverCode;
// init SPI
_spi.format(8,3); // 8 bit spi mode 3
_spi.frequency(16000000); // 16Mhz SPI clock ... 15Mhz is maximum for display, but it seems to work
// reset exactly like in Arduino version
_cs = 0;
_reset = 1; // reset
wait_ms(500);
_reset = 0; // reset
wait_ms(500);
_reset = 1; // reset
wait_ms(500);
/* Start Initial Sequence ----------------------------------------------------*/
wr_cmd(ST7735_SWRESET); /* SW Reset */
wait_ms(150);
wr_cmd(ST7735_SLPOUT); /* Out of sleepmode */
wait_ms(500);
wr_cmd(ST7735_FRMCTR1); /* Frame rate in normal mode */
wr_dat(0x01);
wr_dat(0x2C);
wr_dat(0x2D);
wr_cmd(ST7735_FRMCTR2); /* Frame rate in idle mode */
wr_dat(0x01);
wr_dat(0x2C);
wr_dat(0x2D);
wr_cmd(ST7735_FRMCTR3); /* Frame rate in partial mode */
wr_dat(0x01);
wr_dat(0x2C);
wr_dat(0x2D);
wr_dat(0x01); // inversion mode settings
wr_dat(0x2C);
wr_dat(0x2D);
wr_cmd(ST7735_INVCTR); // Inverted mode off
wr_dat(0x07);
wr_cmd(ST7735_PWCTR1); // POWER CONTROL 1
wr_dat(0xA2);
wr_dat(0x02); // -4.6V
wr_dat(0x84); // AUTO mode
wr_cmd(ST7735_PWCTR2); // POWER CONTROL 2
wr_dat(0xC5); // VGH25 = 2.4C VGSEL =-10 VGH = 3*AVDD
wr_cmd(ST7735_PWCTR3); // POWER CONTROL 3
wr_dat(0x0A); // Opamp current small
wr_dat(0x00); // Boost freq
wr_cmd(ST7735_PWCTR4); // POWER CONTROL 4
wr_dat(0x8A); // BCLK/2, Opamp current small / medium low
wr_dat(0x2A); //
wr_cmd(ST7735_PWCTR5); // POWER CONTROL 5
wr_dat(0x8A); // BCLK/2, Opamp current small / medium low
wr_dat(0xEE); //
wr_cmd(ST7735_VMCTR1); // POWER CONTROL 6
wr_dat(0x0E); //
wr_cmd(ST7735_INVOFF); // INVOFF
wr_cmd(ST7735_MADCTL); // ORIENTATION
wr_dat(0xC8); //
wr_cmd(ST7735_COLMOD); // COLOR MODE
wr_dat(0x05); //
wr_cmd(ST7735_CASET); // COLUMN ADDR SET
wr_dat(0x00); //
wr_dat(0x00); // xstart = 0
wr_dat(0x00); //
wr_dat(0x7F); // xend = 127
wr_cmd(ST7735_RASET); // ROW ADDR SET
wr_dat(0x00); //
wr_dat(0x00); // ystart = 0
wr_dat(0x00); //
wr_dat(0x9F); // yend = 159
/* Gamma settings -----------------------------------------------------------*/
wr_cmd(0xE0); // GMCTRP1
wr_dat(0x02);
wr_dat(0x1c);
wr_dat(0x07);
wr_dat(0x12);
wr_dat(0x37);
wr_dat(0x32);
wr_dat(0x29);
wr_dat(0x2d);
wr_dat(0x29);
wr_dat(0x25);
wr_dat(0x2B);
wr_dat(0x39);
wr_dat(0x00);
wr_dat(0x01);
wr_dat(0x03);
wr_dat(0x10);
wr_cmd(0xE1); // GMCTRN1
wr_dat(0x03);
wr_dat(0x1d);
wr_dat(0x07);
wr_dat(0x06);
wr_dat(0x2E);
wr_dat(0x2C);
wr_dat(0x29);
wr_dat(0x2D);
wr_dat(0x2E);
wr_dat(0x2E);
wr_dat(0x37);
wr_dat(0x3F);
wr_dat(0x00);
wr_dat(0x00);
wr_dat(0x02);
wr_dat(0x10);
wr_cmd(ST7735_DISPON); // display ON
wait_ms(100);
wr_cmd(ST7735_NORON); // normal display on
wait_ms(10);
switch (orientation) {
case 0:
wr_reg(0xC8, 0x0008);
break;
case 1:
wr_reg(0xC8, 0x0068);
break;
case 2:
wr_reg(0xC8, 0x00C8);
break;
case 3:
wr_reg(0xC8, 0x00A8);
break;
}
WindowMax ();
}
void ST7735_TFT::pixel(int x, int y, int color) {
if ((x >= width()) || (y >= height())) return;
window(x,y,x+1,y+1);
// setup for data
_rs = 1;
_cs = 0;
_spi.format(16,3);
_spi.write(color);
_cs = 1;
_spi.format(8,3);
}
void ST7735_TFT::window (unsigned int x, unsigned int y, unsigned int w, unsigned int h) {
wr_cmd(ST7735_CASET); // column addr set
wr_dat(0x00);
wr_dat(x+2); // XSTART
wr_dat(0x00);
wr_dat(x+w+1); // XEND
wr_cmd(ST7735_RASET); // row addr set
wr_dat(0x00);
wr_dat(y+1); // YSTART
wr_dat(0x00);
wr_dat(y+h+1); // YEND
wr_cmd(ST7735_RAMWR); // write to RAM
}
void ST7735_TFT::WindowMax (void) {
window (0, 0, width(), height());
}
void ST7735_TFT::cls (void) {
fillrect(-2,-2,128,160,(0x0000)); // This clears the complete screen to BLACK
}
/*
void ST7735_TFT::cls (void) { // This does not completely clear the screen edges
unsigned int i;
WindowMax();
wr_dat_start();
_spi.format(8,3);
for (i = 0; i < ( (width()+1) * (height()+3)); i++) {
_spi.write(_background);
}
_spi.format(8,3);
wr_dat_stop();
}
*/
void ST7735_TFT::circle(int x0, int y0, int r, int color) {
int draw_x0, draw_y0;
int draw_x1, draw_y1;
int draw_x2, draw_y2;
int draw_x3, draw_y3;
int draw_x4, draw_y4;
int draw_x5, draw_y5;
int draw_x6, draw_y6;
int draw_x7, draw_y7;
int xx, yy;
int di;
WindowMax();
if (r == 0) { /* no radius */
return;
}
draw_x0 = draw_x1 = x0;
draw_y0 = draw_y1 = y0 + r;
if (draw_y0 < height()) {
pixel(draw_x0, draw_y0, color); /* 90 degree */
}
draw_x2 = draw_x3 = x0;
draw_y2 = draw_y3 = y0 - r;
if (draw_y2 >= 0) {
pixel(draw_x2, draw_y2, color); /* 270 degree */
}
draw_x4 = draw_x6 = x0 + r;
draw_y4 = draw_y6 = y0;
if (draw_x4 < width()) {
pixel(draw_x4, draw_y4, color); /* 0 degree */
}
draw_x5 = draw_x7 = x0 - r;
draw_y5 = draw_y7 = y0;
if (draw_x5>=0) {
pixel(draw_x5, draw_y5, color); /* 180 degree */
}
if (r == 1) {
return;
}
di = 3 - 2*r;
xx = 0;
yy = r;
while (xx < yy) {
if (di < 0) {
di += 4*xx + 6;
} else {
di += 4*(xx - yy) + 10;
yy--;
draw_y0--;
draw_y1--;
draw_y2++;
draw_y3++;
draw_x4--;
draw_x5++;
draw_x6--;
draw_x7++;
}
xx++;
draw_x0++;
draw_x1--;
draw_x2++;
draw_x3--;
draw_y4++;
draw_y5++;
draw_y6--;
draw_y7--;
if ( (draw_x0 <= width()) && (draw_y0>=0) ) {
pixel(draw_x0, draw_y0, color);
}
if ( (draw_x1 >= 0) && (draw_y1 >= 0) ) {
pixel(draw_x1, draw_y1, color);
}
if ( (draw_x2 <= width()) && (draw_y2 <= height()) ) {
pixel(draw_x2, draw_y2, color);
}
if ( (draw_x3 >=0 ) && (draw_y3 <= height()) ) {
pixel(draw_x3, draw_y3, color);
}
if ( (draw_x4 <= width()) && (draw_y4 >= 0) ) {
pixel(draw_x4, draw_y4, color);
}
if ( (draw_x5 >= 0) && (draw_y5 >= 0) ) {
pixel(draw_x5, draw_y5, color);
}
if ( (draw_x6 <=width()) && (draw_y6 <= height()) ) {
pixel(draw_x6, draw_y6, color);
}
if ( (draw_x7 >= 0) && (draw_y7 <= height()) ) {
pixel(draw_x7, draw_y7, color);
}
}
return;
}
void ST7735_TFT::fillcircle(int x, int y, int r, int color) {
int i;
for (i = 0; i <= r; i++)
circle(x,y,i,color);
}
void ST7735_TFT::hline(int x0, int x1, int y, int color) {
int w;
w = x1 - x0 + 1;
window(x0,y,w,1);
wr_cmd(0x2C);
wr_dat_start();
for (int x=0; x<w; x++) {
_spi.write(color);
_spi.write(color >> 8);
}
wr_dat_stop();
return;
}
void ST7735_TFT::vline(int x, int y0, int y1, int color) {
int h;
h = y1 - y0 + 1;
window(x,y0,1,h);
wr_cmd(0x2C);
wr_dat_start();
for (int y=0; y<h; y++) {
_spi.write(color);
_spi.write(color >> 8);
}
wr_dat_stop();
return;
}
void ST7735_TFT::line(int x0, int y0, int x1, int y1, int color) {
WindowMax();
int dx = 0, dy = 0;
int dx_sym = 0, dy_sym = 0;
int dx_x2 = 0, dy_x2 = 0;
int di = 0;
dx = x1-x0;
dy = y1-y0;
if (dx == 0) { /* vertical line */
if (y1 > y0) vline(x0,y0,y1,color);
else vline(x0,y1,y0,color);
return;
}
if (dx > 0) {
dx_sym = 1;
} else {
dx_sym = -1;
}
if (dy == 0) { /* horizontal line */
if (x1 > x0) hline(x0,x1,y0,color);
else hline(x1,x0,y0,color);
return;
}
if (dy > 0) {
dy_sym = 1;
} else {
dy_sym = -1;
}
dx = dx_sym*dx;
dy = dy_sym*dy;
dx_x2 = dx*2;
dy_x2 = dy*2;
if (dx >= dy) {
di = dy_x2 - dx;
while (x0 != x1) {
pixel(x0, y0, color);
x0 += dx_sym;
if (di<0) {
di += dy_x2;
} else {
di += dy_x2 - dx_x2;
y0 += dy_sym;
}
}
pixel(x0, y0, color);
} else {
di = dx_x2 - dy;
while (y0 != y1) {
pixel(x0, y0, color);
y0 += dy_sym;
if (di < 0) {
di += dx_x2;
} else {
di += dx_x2 - dy_x2;
x0 += dx_sym;
}
}
pixel(x0, y0, color);
}
return;
}
void ST7735_TFT::rect(int x0, int y0, int x1, int y1, int color) {
if (x1 > x0) hline(x0,x1,y0,color);
else hline(x1,x0,y0,color);
if (y1 > y0) vline(x0,y0,y1,color);
else vline(x0,y1,y0,color);
if (x1 > x0) hline(x0,x1,y1,color);
else hline(x1,x0,y1,color);
if (y1 > y0) vline(x1,y0,y1,color);
else vline(x1,y1,y0,color);
return;
}
void ST7735_TFT::fillrect(int x0, int y0, int x1, int y1, int color) {
int h = y1 - y0 + 1;
int w = x1 - x0 + 1;
int pixel = h * w;
window(x0,y0,w,h);
wr_cmd(0x2C);
wr_dat_start();
for (int p=0; p<pixel; p++) {
_spi.write(color);
_spi.write(color >> 8);
}
wr_dat_stop();
return;
}
void ST7735_TFT::locate(int x, int y) {
char_x = x;
char_y = y;
}
int ST7735_TFT::columns() {
return width() / font[1];
}
int ST7735_TFT::rows() {
return height() / font[2];
}
int ST7735_TFT::_putc(int value) {
if (value == '\n') { // new line
char_x = 0;
char_y = char_y + font[2];
if (char_y >= height() - font[2]) {
char_y = 0;
}
} else {
character(char_x, char_y, value);
}
return value;
}
void ST7735_TFT::character(int x, int y, int c) {
unsigned int hor,vert,offset,bpl,j,i,b;
unsigned char* sign;
unsigned char z,w;
if ((c < 31) || (c > 127)) return; // test char range
// read font parameter from start of array
offset = font[0]; // bytes / char
hor = font[1]; // get hor size of font
vert = font[2]; // get vert size of font
bpl = font[3]; // bytes per line
if (char_x + hor > width()) {
char_x = 0;
char_y = char_y + vert;
if (char_y >= height() - font[2]) {
char_y = 0;
}
}
window(char_x, char_y,hor,vert); // char box
wr_cmd(0x2C);
wr_dat_start();
sign = &font[((c -32) * offset) + 4]; // start of char bitmap
w = sign[0]; // width of actual char
_spi.format(16,3); // pixel are 16 bit
for (j=0; j<vert; j++) { // vert line
for (i=0; i<hor; i++) { // horz line
z = sign[bpl * i + ((j & 0xF8) >> 3)+1];
b = 1 << (j & 0x07);
if (( z & b ) == 0x00) {
_spi.write(_background);
} else {
_spi.write(_foreground);
}
}
}
_spi.format(8,3); // 8 bit
wr_dat_stop();
if ((w + 2) < hor) { // x offset to next char
char_x += w + 2;
} else char_x += hor;
}
void ST7735_TFT::set_font(unsigned char* f) {
font = f;
}
void ST7735_TFT::Bitmap(unsigned int x, unsigned int y, unsigned int w, unsigned int h,unsigned char *bitmap) {
unsigned int i,j; //value;
unsigned short *bitmap_ptr = (unsigned short *)bitmap;
window(x, y, w, h);
wr_cmd(0x2C);
wr_dat_start();
for (j = 0; j < h; j++) { //Lines
for (i = 0; i < w; i++) { // copy pixel data to TFT
_spi.write(*bitmap_ptr); // one line
_spi.write(*bitmap_ptr >> 8);
bitmap_ptr++;
}
}
wr_dat_stop();
}
int ST7735_TFT::BMP_16(unsigned int x, unsigned int y, const char *Name_BMP) {
// BEWARE !
// NOT TESTED
#define OffsetPixelWidth 18
#define OffsetPixelHeigh 22
#define OffsetFileSize 34
#define OffsetPixData 10
#define OffsetBPP 28
char filename[50];
unsigned char BMP_Header[54];
unsigned short BPP_t;
unsigned int PixelWidth,PixelHeigh,start_data;
unsigned int i,off;
int padd,j;
unsigned short *line;
// get the filename
//LocalFileSystem local("local");
sprintf(&filename[0],"/local/");
i=7;
while (*Name_BMP!='\0') {
filename[i++]=*Name_BMP++;
}
FILE *Image = fopen((const char *)&filename[0], "r"); // open the bmp file
if (!Image) {
return(0); // error file not found !
}
fread(&BMP_Header[0],1,54,Image); // get the BMP Header
if (BMP_Header[0] != 0x42 || BMP_Header[1] != 0x4D) { // check magic byte
fclose(Image);
return(-1); // error no BMP file
}
BPP_t = BMP_Header[OffsetBPP] + (BMP_Header[OffsetBPP + 1] << 8);
if (BPP_t != 0x0010) {
fclose(Image);
return(-2); // error no 16 bit BMP
}
PixelHeigh = BMP_Header[OffsetPixelHeigh] + (BMP_Header[OffsetPixelHeigh + 1] << 8) + (BMP_Header[OffsetPixelHeigh + 2] << 16) + (BMP_Header[OffsetPixelHeigh + 3] << 24);
PixelWidth = BMP_Header[OffsetPixelWidth] + (BMP_Header[OffsetPixelWidth + 1] << 8) + (BMP_Header[OffsetPixelWidth + 2] << 16) + (BMP_Header[OffsetPixelWidth + 3] << 24);
if (PixelHeigh > height() + y || PixelWidth > width() + x) {
fclose(Image);
return(-3); // to big
}
start_data = BMP_Header[OffsetPixData] + (BMP_Header[OffsetPixData + 1] << 8) + (BMP_Header[OffsetPixData + 2] << 16) + (BMP_Header[OffsetPixData + 3] << 24);
line = (unsigned short *) malloc (PixelWidth); // we need a buffer for a line
if (line == NULL) {
return(-4); // error no memory
}
// the lines are padded to multiple of 4 bytes
padd = -1;
do {
padd ++;
} while ((PixelWidth * 2 + padd)%4 != 0);
window(x, y,PixelWidth,PixelHeigh);
wr_cmd(0x2C);
wr_dat_start();
_spi.format(16,3);
for (j = PixelHeigh - 1; j >= 0; j--) { //Lines bottom up
off = j * (PixelWidth * 2 + padd) + start_data; // start of line
fseek(Image, off ,SEEK_SET);
fread(line,1,PixelWidth * 2,Image); // read a line - slow !
for (i = 0; i < PixelWidth; i++) { // copy pixel data to TFT
_spi.write(line[i]); // one 16 bit pixel
}
}
_spi.format(8,3);
wr_dat_stop();
free (line);
fclose(Image);
return(1);
}
See your fillrect function for example, you can easily split it in two seperate 8-bit writes:
_spi.write(color); _spi.write(color >> 8);
Thank you Eric, works fine see code change below. (Must be great if you know what your doing!!)
for (j=0; j<vert; j++) { vert line for (i=0; i<hor; i++) { horz line z = sign[bpl * i + ((j & 0xF8) >> 3)+1]; b = 1 << (j & 0x07); if (( z & b ) == 0x00) { _spi.write(_background); code changed for 8 bit operation _spi.write(_background>>8); code changed for 8 bit operation } else { _spi.write(_foreground); code changed for 8 bit operation _spi.write(_foreground>>8); code changed for 8 bit operation } } }
posted by 21 Mar 2013If you want to build a lib which is running on all plattforms you can use :
#if defined TARGET_KL25Z .... 8 bit #else ... 16bit #endif
to build different on versions. Have a look on my original tft lib : http://mbed.org/users/dreschpe/code/SPI_TFT/ This is patched to run on the KL25Z.
posted by 22 Mar 2013