File content as of revision 15:516f15979b53:

#include "mbed.h"
#include "LCD_ST7735.h"

LCD_ST7735::LCD_ST7735(
    PinName backlightPin,
    PinName resetPin,
    PinName dsPin,
    PinName mosiPin,
    PinName misoPin,
    PinName clkPin,
    PinName csPin,
    PanelColorFilter colorFilter
    ) :
        _colorFilter(colorFilter),
        _backlight(backlightPin, 0),
        _reset(resetPin, 1),
        _ds(dsPin, 0),
        _cs(csPin, 1),
        _spi(mosiPin, misoPin, clkPin)        
{        
    _spi.format(8, 3);
    _spi.frequency(15000000);
    
    initDisplay();
    clearScreen();
    setForegroundColor(0xffff);
    setBackgroundColor(0x0000);
}

void LCD_ST7735::setOrientation(Orientation orientation, bool flip)
{
    const static uint8_t my = 0x80; 
    const static uint8_t mx = 0x40;
    const static uint8_t mv = 0x20;
    
    uint8_t madctlData = _colorFilter;
    switch(orientation)
    {
        case Rotate0:
            _width = 128;
            _height = 160;
            madctlData |= flip ? mx : 0;
            break;
            
        case Rotate90:
            _width = 160;
            _height = 128;
            madctlData |= flip ? my | mv | mx : mv | mx;
            break;
            
        case Rotate180:
            _width = 128;
            _height = 160;
            madctlData |= flip ? my : mx | my;
            break;
            
        case Rotate270:
            _width = 160;
            _height = 128;
            madctlData |= flip ? mv : mv | my;
            break;
    }
    write(CMD_MADCTL, (uint8_t[]){madctlData}, 1);
}

int LCD_ST7735::getWidth()
{
    return _width;
}
        
int LCD_ST7735::getHeight()
{
    return _height;
}

void LCD_ST7735::setBacklight(bool state)
{
    _backlight = state ? 1 : 0;
}

void LCD_ST7735::clearScreen(uint16_t color)
{
    clipRect(0, 0, _width - 1, _height - 1);
    beginBatchCommand(CMD_RAMWR);
    uint8_t colorHigh = color >> 8;
    uint8_t colorLow = color;
    for(int i = 0; i < 128 * 160 * 2; ++i)
    {
        writeBatchData(colorHigh, colorLow);
    }
    endBatchCommand();
}

void LCD_ST7735::setPixel(int x, int y, uint16_t color)
{
    write(CMD_CASET, (uint8_t[]){0, x, 0, x}, 4);    
    write(CMD_RASET, (uint8_t[]){0, y, 0, y}, 4);    
    write(CMD_RAMWR, color);
}

void LCD_ST7735::drawLine(int x1, int y1, int x2, int y2, uint16_t color)
{
    int dx = abs(x2 - x1);
    int dy = abs(y2 - y1);
    
    if (dx == 0) 
    {
        drawVertLine(x1, y1, y2, color);
        return;
    }
    else if(dy == 0)
    {
        drawHorizLine(x1, y1, x2, color);
        return;
    }
   
    int sx = (x1 < x2) ? 1 : -1;
    int sy = (y1 < y2) ? 1 : -1;
    int err = dx - dy;
    while(x1 != x2 || y1 != y2)
    {
        setPixel(x1, y1, color);
        int e2 = err << 1;
        if (e2 > -dy)
        {
            err -= dy;
            x1 += sx;            
        }
        if (e2 < dx)
        {
            err += dx;
            y1 += sy;
        }
    }
    setPixel(x2, y2, color);
}

void LCD_ST7735::swap(int &a, int &b)
{
    int t = a;
    a = b;
    b = t;
}

void LCD_ST7735::drawRect(int x1, int y1, int x2, int y2, uint16_t color)
{
    if (x1 > x2) swap(x1, x2);
    if (y1 > y2) swap(y1, y2);
    
    drawHorizLine(x1, y1, x2, color);
    drawHorizLine(x1, y2, x2, color);
    drawVertLine(x1, y1, y2, color);
    drawVertLine(x2, y1, y2, color);
}

void LCD_ST7735::drawCircle(int x, int y, int r, uint16_t color)
{
    int ix = r;
    int iy = 0;
    int err = 1 - r;
    
    while(ix >= iy)
    {
        setPixel(x + ix, y + iy, color);
        setPixel(x + iy, y + ix, color);
        setPixel(x - ix, y + iy, color);
        setPixel(x - iy, y + ix, color);
        setPixel(x - ix, y - iy, color);
        setPixel(x - iy, y - ix, color);
        setPixel(x + ix, y - iy, color);
        setPixel(x + iy, y - ix, color);
        iy++;
        if (err < 0)
        {
            err += 2 * iy + 1;
        }
        else
        {
            ix--;
            err += 2 * (iy - ix + 1);
        }
    }
}

void LCD_ST7735::drawEllipse(int x, int y, int rx, int ry, uint16_t color)
{
    int a2 = rx * rx;
    int b2 = ry * ry;
    int fa2 = 4 * a2;
    int fb2 = 4 * b2;
    
    int ix, iy, sigma;    
    for (ix = 0, iy = ry, sigma = 2 * b2 + a2 * (1 - 2 * ry); b2 * ix <= a2 * iy; ix++)
    {
        setPixel(x + ix, y + iy, color);
        setPixel(x - ix, y + iy, color);
        setPixel(x + ix, y - iy, color);
        setPixel(x - ix, y - iy, color);
        if (sigma >= 0)
        {
            sigma+= fa2 * (1 - iy);
            iy--;
        }
        sigma += b2 * ((4 * ix) + 6);
    }
    
    for (ix = rx, iy = 0, sigma = 2 * a2 + b2 * (1 - 2 * rx); a2 * iy <= b2 * ix; iy++)
    {
        setPixel(x + ix, y + iy, color);
        setPixel(x - ix, y + iy, color);
        setPixel(x + ix, y - iy, color);
        setPixel(x - ix, y - iy, color);
        if (sigma >= 0)
        {
            sigma+= fb2 * (1 - ix);
            ix--;
        }
        sigma += a2 * ((4 * iy) + 6);
    }
}
void LCD_ST7735::fillRect(int x1, int y1, int x2, int y2, uint16_t fillColor)
{
    if (x1 > x2) swap(x1, x2);
    if (y1 > y2) swap(y1, y2);
    
    clipRect(x1, y1, x2, y2);
    int c = (((x2 - x1) + 1) * ((y2 - y1) + 1));
    uint8_t colorHigh = fillColor >> 8;
    uint8_t colorLow = fillColor;
    beginBatchCommand(CMD_RAMWR);
    while(c--)
    {
        writeBatchData(colorHigh, colorLow);
    }
    endBatchCommand();
}

void LCD_ST7735::fillRect(int x1, int y1, int x2, int y2, uint16_t borderColor, uint16_t fillColor)
{
    if (x1 > x2) swap(x1, x2);
    if (y1 > y2) swap(y1, y2);
    
    drawRect(x1, y1, x2, y2, borderColor);
    ++x1; ++y1; --x2; --y2;
    if (x2 >= x1 && y2 >= y1)
    {           
        int c = (((x2 - x1) + 1) * ((y2 - y1) + 1));
            
        clipRect(x1, y1, x2, y2);        
        uint8_t colorHigh = fillColor >> 8;
        uint8_t colorLow = fillColor;
        beginBatchCommand(CMD_RAMWR);
        while(c--)
        {
            writeBatchData(colorHigh, colorLow);
        }
        endBatchCommand();
    }
}

void LCD_ST7735::fillCircle(int x, int y, int r, uint16_t borderColor, uint16_t fillColor)
{
    int ix = r;
    int iy = 0;
    int err = 1 - r;
    
    while(ix >= iy)
    {
        setPixel(x - ix, y + iy, borderColor);
        setPixel(x + ix, y + iy, borderColor);        
        drawHorizLine(x - ix + 1, y + iy, x + ix - 1, fillColor);
        
        setPixel(x - iy, y + ix, borderColor);
        setPixel(x + iy, y + ix, borderColor);                
        drawHorizLine(x - iy + 1, y + ix, x + iy - 1, fillColor);
                
        setPixel(x - ix, y - iy, borderColor);
        setPixel(x + ix, y - iy, borderColor);
        drawHorizLine(x - ix + 1, y - iy, x + ix - 1, fillColor);
        
        setPixel(x - iy, y - ix, borderColor);        
        setPixel(x + iy, y - ix, borderColor);
        drawHorizLine(x - iy + 1, y - ix, x + iy - 1, fillColor);
        iy++;
        if (err < 0)
        {
            err += 2 * iy + 1;
        }
        else
        {
            ix--;
            err += 2 * (iy - ix + 1);
        }
    }
}

void LCD_ST7735::fillEllipse(int x, int y, int rx, int ry, uint16_t borderColor, uint16_t fillColor)
{
    int a2 = rx * rx;
    int b2 = ry * ry;
    int fa2 = 4 * a2;
    int fb2 = 4 * b2;
    
    int ix, iy, sigma;    
    for (ix = 0, iy = ry, sigma = 2 * b2 + a2 * (1 - 2 * ry); b2 * ix <= a2 * iy; ix++)
    {
        setPixel(x + ix, y + iy, borderColor);
        setPixel(x - ix, y + iy, borderColor);
        drawHorizLine(x - ix + 1, y + iy, x + ix - 1, fillColor);
        
        setPixel(x + ix, y - iy, borderColor);
        setPixel(x - ix, y - iy, borderColor);
        drawHorizLine(x - ix + 1, y - iy, x + ix - 1, fillColor);
        
        if (sigma >= 0)
        {
            sigma+= fa2 * (1 - iy);
            iy--;
        }
        sigma += b2 * ((4 * ix) + 6);
    }
    
    for (ix = rx, iy = 0, sigma = 2 * a2 + b2 * (1 - 2 * rx); a2 * iy <= b2 * ix; iy++)
    {
        setPixel(x + ix, y + iy, borderColor);
        setPixel(x - ix, y + iy, borderColor);
        drawHorizLine(x - ix + 1, y + iy, x + ix - 1, fillColor);
        
        setPixel(x + ix, y - iy, borderColor);
        setPixel(x - ix, y - iy, borderColor);
        drawHorizLine(x - ix + 1, y - iy, x + ix - 1, fillColor);
        if (sigma >= 0)
        {
            sigma+= fb2 * (1 - ix);
            ix--;
        }
        sigma += a2 * ((4 * iy) + 6);
    }
}

void LCD_ST7735::drawBitmap(int x, int y, const uint16_t *pbmp)
{
    int w = *pbmp++;
    int h = *pbmp++;
    
    clip(x, y, w, h);
    int c = w * h;
    beginBatchCommand(CMD_RAMWR);
    while(c--)
    {
        writeBatchData(*pbmp++);
    }
    endBatchCommand();
}

void LCD_ST7735::drawBitmap(int x, int y, const uint16_t *pbmp, int srcX, int srcY, int srcWidth, int srcHeight)
{
    int w = *pbmp++;
    int h = *pbmp++;
    
    clip(x, y, srcWidth, srcHeight);
    beginBatchCommand(CMD_RAMWR);    
    const uint16_t *p = pbmp + srcX + (srcY * w);
    for(int iy = 0; iy < srcHeight; ++iy)
    {
        for(int ix = 0; ix < srcWidth; ++ix)
        {
            writeBatchData(*(p + ix));
        }
        p += w;
    } 
    endBatchCommand();
}

void LCD_ST7735::setForegroundColor(uint16_t color)
{
    _foregroundColorHigh = color >> 8;
    _foregroundColorLow = color;
}

void LCD_ST7735::setBackgroundColor(uint16_t color)
{
    _backgroundColorHigh = color >> 8;
    _backgroundColorLow = color;
}
        
void LCD_ST7735::drawString(const uint8_t *pFont, int x, int y, const char *pString)
{
    uint8_t w = *pFont;
    uint8_t h = *(pFont + 1);
    uint8_t offset = *(pFont + 2);
    uint8_t leftPad = *(pFont + 3);
    uint8_t rightPad = *(pFont + 4);
    uint8_t topPad = *(pFont + 5);
    uint8_t bottomPad = *(pFont + 6);
    
    if (y + topPad + h + bottomPad < 0) return;
    if (y >= _height) return;
    if (x + leftPad + w + rightPad < 0) return;    
    
    char *p = (char*)pString;
    while(*p != 0)
    {        
        if (x >= _width) return;
        drawChar(pFont, x, y, *p++, w, h, offset, leftPad, rightPad, topPad, bottomPad);
        x += (w + leftPad + rightPad);
    }
}

void LCD_ST7735::measureString(const uint8_t *pFont, const char *pString, uint8_t &width, uint8_t &height)
{
    uint8_t w = *pFont;
    uint8_t h = *(pFont + 1);
    uint8_t leftPad = *(pFont + 3);
    uint8_t rightPad = *(pFont + 4);
    uint8_t topPad = *(pFont + 5);
    uint8_t bottomPad = *(pFont + 6);
    
    width = (w + leftPad + rightPad) * strlen(pString);
    height = (h + topPad + bottomPad);
}

void LCD_ST7735::selectDevice()
{
    _spi.prepareFastSPI();
}

void LCD_ST7735::drawVertLine(int x1, int y1, int y2, uint16_t color)
{
    clipRect(x1, y1, x1, y2);
    beginBatchCommand(CMD_RAMWR);
    int c = (y2 - y1) << 1;
    uint8_t colorHigh = color >> 8;
    uint8_t colorLow = color;
    for (int i = 0; i < c; ++i)
    {
        writeBatchData(colorHigh, colorLow);        
    }
    endBatchCommand();
}

void LCD_ST7735::drawHorizLine(int x1, int y1, int x2, uint16_t color)
{
    clipRect(x1, y1, x2, y1);
    beginBatchCommand(CMD_RAMWR);
    int c = (x2 - x1) << 1;
    uint8_t colorHigh = color >> 8;
    uint8_t colorLow = color;
    for (int i = 0; i < c; ++i)
    {
        writeBatchData(colorHigh, colorLow);
    }
    endBatchCommand();
}

void LCD_ST7735::drawChar(const uint8_t *pFont, int x, int y, char c, uint8_t w, uint8_t h, uint8_t offset, uint8_t leftPad, uint8_t rightPad, uint8_t topPad, uint8_t bottomPad)
{
    const uint8_t *pChar = (pFont + 7) + ((c - offset) * h);
    
    clip(x, y, w + leftPad + rightPad, h + topPad + bottomPad);
    
    beginBatchCommand(CMD_RAMWR);
    
    // Render top spacing
    for (int r = 0; r < topPad; ++r)
    {
        for (int c = 0; c < w + leftPad + rightPad; ++c)
        {
            writeBatchData(_backgroundColorHigh);
            writeBatchData(_backgroundColorLow);
        }
    }
    
    // Render character
    for(int r = 0; r < h; ++r)
    {
        uint8_t b = pChar[r];
        
        // Render left spacing
        for (int c = 0; c < leftPad; ++c)
        {
            writeBatchData(_backgroundColorHigh);
            writeBatchData(_backgroundColorLow);
        }        
        for(int c = 0; c < w; ++c)
        {
            if (b & 0x80)
            {
                writeBatchData(_foregroundColorHigh);
                writeBatchData(_foregroundColorLow);
            }
            else
            {
                writeBatchData(_backgroundColorHigh);
                writeBatchData(_backgroundColorLow);
            }
                
            b <<= 1;
        }
        
        for (int c = 0; c < rightPad; ++c)
        {
            writeBatchData(_backgroundColorHigh);
            writeBatchData(_backgroundColorLow);
        }        
    }
    
    // Render bottom spacing
    for (int r = 0; r < bottomPad; ++r)
    {
        for (int c = 0; c < w + leftPad + rightPad; ++c)
        {
            writeBatchData(_backgroundColorHigh);
            writeBatchData(_backgroundColorLow);
        }
    }
    endBatchCommand();
}

void LCD_ST7735::initDisplay()
{
    selectDevice();
    reset();
    
    writeCommand(CMD_SLPOUT);
    
    write(CMD_FRMCTR1, (uint8_t[]){0x01, 0x2c, 0x2d}, 3);
    write(CMD_FRMCTR2, (uint8_t[]){0x01, 0x2c, 0x2d}, 3);
    write(CMD_FRMCTR3, (uint8_t[]){0x01, 0x2c, 0x2d, 0x01, 0x2c, 0x2d}, 6);
    
    write(CMD_INVCTR, (uint8_t[]){0x07}, 1);
    
    write(CMD_PWCTR1, (uint8_t[]){0xa2, 0x02, 0x84}, 3);
    write(CMD_PWCTR2, (uint8_t[]){0xc5}, 1);
    write(CMD_PWCTR3, (uint8_t[]){0x0a, 0x00}, 2);
    write(CMD_PWCTR4, (uint8_t[]){0x8a, 0x2a}, 2);
    write(CMD_PWCTR5, (uint8_t[]){0x8a, 0xee}, 2);
    
    write(CMD_VMCTR1, (uint8_t[]){0x0e}, 1);
    
    write(CMD_MADCTL, (uint8_t[]){0xc0 | _colorFilter}, 1);
    
    // Gama sequence
    write(CMD_GAMCTRP1, (uint8_t[])
        {
            0x0f, 0x1a,
            0x0f, 0x18,
            0x2f, 0x28,
            0x20, 0x22,
            0x1f, 0x1b,
            0x23, 0x37,
            0x00, 0x07,
            0x02, 0x10
        }, 16);
        
    write(CMD_GAMCTRN1, (uint8_t[])
        {
            0x0f, 0x1b,
            0x0f, 0x17,
            0x33, 0x2c,
            0x29, 0x2e,
            0x30, 0x30,
            0x39, 0x3f,
            0x00, 0x07,
            0x03, 0x10
        }, 16);
        
    write(CMD_CASET, (uint8_t[]){0x00, 0x00, 0x00, 0x7f}, 4);
    write(CMD_RASET, (uint8_t[]){0x00, 0x00, 0x00, 0x9f}, 4);
    
    write(CMD_EXTCTRL, (uint8_t[]){0x01}, 1);            
    
    // Disable RAM power save
    write(0xf6, (uint8_t[]){0x00}, 1);                    
    
    // 65k color mode
    write(CMD_COLMOD, (uint8_t[]){0x05}, 1);            
    
    // Enable display
    writeCommand(CMD_DISPON);            
    
    setBacklight(true);
}

void LCD_ST7735::reset()
{
    _reset = 0;
    wait_us(100);
    _reset = 1;
    wait_us(100);
}

void LCD_ST7735::clip(int x, int y, int w, int h)
{
    clipRect(x, y, (x + w) - 1, (y + h) - 1);
}

void LCD_ST7735::clipRect(int x1, int y1, int x2, int y2)
{
    uint8_t x1l = (uint8_t)x1;
    uint8_t x1h = (uint8_t)(x1 >> 8);
    uint8_t x2l = (uint8_t)x2;
    uint8_t x2h = (uint8_t)(x2 >> 8);
    write(CMD_CASET, (uint8_t[]){x1h, x1l, x2h, x2l}, 4);    
    
    uint8_t y1l = (uint8_t)y1;
    uint8_t y1h = (uint8_t)(y1 >> 8);
    uint8_t y2l = (uint8_t)y2;
    uint8_t y2h = (uint8_t)(y2 >> 8);
    write(CMD_RASET, (uint8_t[]){y1h, y1l, y2h, y2l}, 4);    
}
        
void LCD_ST7735::writeCommand(uint8_t cmd)
{
    _cs = 0;
    _ds = 0;    
    _spi.fastWrite(cmd);
    _spi.waitWhileBusy();
    _spi.clearRx();
    _cs = 1;
}

void LCD_ST7735::write(uint8_t cmd, uint8_t data[], int dataLen)
{
    _cs = 0;
    _ds = 0;    
    _spi.fastWrite(cmd);
    _spi.waitWhileBusy();
    if (data != NULL & dataLen > 0)
    {
        _ds = 1;        
        for(int i = 0; i < dataLen; ++i)
        {            
            _spi.fastWrite(data[i]); 
        }        
        _spi.waitWhileBusy();
        _ds = 0; 
    }    
    _spi.clearRx();
    _cs = 1;
}

void LCD_ST7735::write(uint8_t cmd, uint16_t data)
{
    _cs = 0; 
    _ds = 0;    
    _spi.fastWrite(cmd);       
    _spi.waitWhileBusy();
    _ds = 1;            
    _spi.fastWrite(data >> 8);
    _spi.fastWrite(data);
    _spi.waitWhileBusy();
    _spi.clearRx();
    _ds = 0;     
    _cs = 1;
}

void LCD_ST7735::beginBatchCommand(uint8_t cmd)
{
    _cs = 0;
    _ds = 0;        
    _spi.fastWrite(cmd);   
    _spi.waitWhileBusy();
    _ds = 1;
}

void LCD_ST7735::writeBatchData(uint8_t data)
{
    _spi.fastWrite(data);
}

void LCD_ST7735::writeBatchData(uint8_t dataHigh, uint8_t dataLow)
{
    _spi.fastWrite(dataHigh);
    _spi.fastWrite(dataLow);
}


void LCD_ST7735::writeBatchData(uint16_t data)
{
    _spi.fastWrite(data >> 8);
    _spi.fastWrite(data); 
}

void LCD_ST7735::endBatchCommand()
{
    _spi.waitWhileBusy();
    _spi.clearRx();
    _ds = 0; 
    _cs = 1; 
}