Diff: ssd1306.cpp

Revision:

6:f552ca0f5165

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ssd1306.cpp	Mon Dec 18 14:00:21 2017 +0000
@@ -0,0 +1,423 @@
+
+#include "mbed.h"
+#include "ssd1306.h"
+
+#include <stdarg.h>
+
+#define pgm_read_byte(addr) (*(const unsigned char *)(addr))
+
+SSD1306::SSD1306(PinName cs, PinName rs, PinName dc, PinName clk, PinName data)
+    : _spi(data, NC, clk), 
+      _cs(cs), 
+      _reset(rs), 
+      _dc(dc),
+      _cursor_x(0),
+      _cursor_y(0)
+{
+}
+
+void SSD1306::off()
+{
+    _send_command(0xAE);
+}
+
+void SSD1306::on()
+{
+    _send_command(0xAF);
+}
+
+void SSD1306::sleep()
+{
+    _send_command(0xAE);
+}
+
+void SSD1306::wake()
+{
+    _send_command(0xAF);
+}
+
+void SSD1306::set_inverse(unsigned char value)
+{
+    _send_command(value ? 0xA7 : 0xA6);
+}
+
+void SSD1306::set_display_offset(unsigned char value)
+{
+    _send_command(0xD3);
+    _send_command(value & 0x3F); 
+}
+
+void SSD1306::set_contrast(unsigned char value) 
+{
+    _send_command(0x81);
+    _send_command(value);
+}
+
+void SSD1306::set_display_start_line(unsigned char value)
+{
+    _send_command(0x40 | value);
+}
+
+void SSD1306::set_segment_remap(unsigned char value)
+{
+    _send_command(value ? 0xA1 : 0xA0);
+}
+
+void SSD1306::set_multiplex_ratio(unsigned char value)
+{
+    _send_command(0xA8);
+    _send_command(value & 0x3F);
+}
+
+void SSD1306::set_com_output_scan_direction(unsigned char value)
+{
+    _send_command(value ? 0xC8 : 0xC0);
+}
+
+void SSD1306::set_com_pins_hardware_configuration(unsigned char sequential, unsigned char lr_remap)
+{
+    _send_command(0xDA);
+    _send_command(0x02 | ((sequential & 1) << 4) | ((lr_remap & 1) << 5));
+}
+
+void SSD1306::start_horizontal_scroll(unsigned char direction, unsigned char start, unsigned char end, unsigned char interval) 
+{
+    _send_command(direction ? 0x27 : 0x26);
+    _send_command(0x00);
+    _send_command(start & 0x07);
+    switch (interval) {
+        case   2: _send_command(0x07); break; // 111b
+        case   3: _send_command(0x04); break; // 100b
+        case   4: _send_command(0x05); break; // 101b
+        case   5: _send_command(0x00); break; // 000b
+        case  25: _send_command(0x06); break; // 110b
+        case  64: _send_command(0x01); break; // 001b
+        case 128: _send_command(0x02); break; // 010b
+        case 256: _send_command(0x03); break; // 011b
+        default:
+            // default to 2 frame interval
+            _send_command(0x07); break;
+    }
+    _send_command(end & 0x07);
+    _send_command(0x00);
+    _send_command(0xFF);
+    
+    // activate scroll
+    _send_command(0x2F);
+}
+
+void SSD1306::start_vertical_and_horizontal_scroll(unsigned char direction, unsigned char start, unsigned char end, unsigned char interval, unsigned char vertical_offset)
+{
+    _send_command(direction ? 0x2A : 0x29);
+    _send_command(0x00);
+    _send_command(start & 0x07);
+    switch (interval) {
+        case   2: _send_command(0x07); break; // 111b
+        case   3: _send_command(0x04); break; // 100b
+        case   4: _send_command(0x05); break; // 101b
+        case   5: _send_command(0x00); break; // 000b
+        case  25: _send_command(0x06); break; // 110b
+        case  64: _send_command(0x01); break; // 001b
+        case 128: _send_command(0x02); break; // 010b
+        case 256: _send_command(0x03); break; // 011b
+        default:
+            // default to 2 frame interval
+            _send_command(0x07); break;
+    }
+    _send_command(end & 0x07);
+    _send_command(vertical_offset);    
+    
+    // activate scroll
+    _send_command(0x2F);
+}
+
+void SSD1306::stop_scroll()
+{
+    // all scroll configurations are removed from the display when executing this command.
+    _send_command(0x2E);
+}
+
+void SSD1306::pam_set_start_address(unsigned char address)
+{
+    // "Set Lower Column Start Address for Page Addressing Mode"
+    _send_command(address & 0x0F);
+    
+    // "Set Higher Column Start Address for Page Addressing Mode"
+    _send_command((address << 4) & 0x0F);
+}
+
+void SSD1306::set_memory_addressing_mode(unsigned char mode)
+{
+    _send_command(0x20);
+    _send_command(mode & 0x3);
+}
+
+void SSD1306::hv_set_column_address(unsigned char start, unsigned char end)
+{
+    _send_command(0x21);
+    _send_command(start & 0x7F);
+    _send_command(end & 0x7F);
+}
+
+void SSD1306::hv_set_page_address(unsigned char start, unsigned char end)
+{
+    _send_command(0x22);
+    _send_command(start & 0x07);
+    _send_command(end & 0x07);
+}
+
+void SSD1306::pam_set_page_start(unsigned char address)
+{
+    _send_command(0xB0 | (address & 0x07));
+}
+
+void SSD1306::set_display_clock_ratio_and_frequency(unsigned char ratio, unsigned char frequency)
+{
+    _send_command(0xD5);
+    _send_command((ratio & 0x0F) | ((frequency & 0x0F) << 4));
+}
+
+void SSD1306::set_precharge_period(unsigned char phase1, unsigned char phase2)
+{
+    _send_command(0xD9);
+    _send_command((phase1 & 0x0F) | ((phase2 & 0x0F ) << 4));
+}
+
+void SSD1306::set_vcomh_deselect_level(unsigned char level)
+{
+    _send_command(0xDB);
+    _send_command((level & 0x03) << 4);
+}
+
+void SSD1306::nop()
+{
+    _send_command(0xE3);
+}
+
+void SSD1306::set_charge_pump_enable(unsigned char enable)
+{
+    _send_command(0x8D);
+    _send_command(enable ? 0x14 : 0x10);
+}
+
+void SSD1306::initialise()
+{
+    // Init
+    _reset = 1;
+    wait(0.01);
+    _reset = 0;
+    wait(0.10);
+    _reset = 1;
+    
+    off();
+
+    set_display_clock_ratio_and_frequency(0, 8);
+    set_multiplex_ratio(0x3F); // 1/64 duty
+    set_precharge_period(0xF, 0x01);
+    set_display_offset(0);    
+    set_display_start_line(0);  
+    set_charge_pump_enable(1);    
+    set_memory_addressing_mode(0); // horizontal addressing mode; across then down
+    set_segment_remap(1);
+    set_com_output_scan_direction(1);
+    set_com_pins_hardware_configuration(1, 0);
+    set_contrast(0xFF);
+    set_vcomh_deselect_level(1);
+    
+    wake();
+    set_inverse(0);
+    
+    hv_set_column_address(0, 127);
+    hv_set_page_address(0, 7);
+    
+    pam_set_start_address(0);
+    pam_set_page_start(0);
+    
+    // set_precharge_period(2, 2);
+}
+
+void SSD1306::update()
+{
+    hv_set_column_address(0, 127);
+    hv_set_page_address(0, 7);
+    
+    for (int i = 0; i < 1024; i++)
+        _send_data(_screen[i]);
+}
+
+void SSD1306::drawBitmap(int x, int y,
+                  const unsigned char *bitmap, int w, int h, int color) {
+  int16_t i, j, byteWidth = (w + 7) / 8;
+
+  for(j=0; j<h; j++) {
+    for(i=0; i<w; i++ ) {
+      if(pgm_read_byte(bitmap + j * byteWidth + i / 8) & (128 >> (i & 7))) {
+        color? set_pixel(x+i, y+j): clear_pixel(x+i, y+j);
+      }
+    }
+  }
+}
+
+void SSD1306::set_pixel(int x, int y)
+{
+    if (x >= SSD1306_LCDWIDTH || y >= SSD1306_LCDHEIGHT) return;
+    
+    _screen[x + (y / 8) * 128] |= 1 << (y % 8);
+}
+
+void SSD1306::clear_pixel(int x, int y)
+{
+    if (x >= SSD1306_LCDWIDTH || y >= SSD1306_LCDHEIGHT) return;
+    
+    _screen[x + (y / 8) * 128] &= ~(1 << (y % 8));
+}
+
+void SSD1306::line(int x0, int y0, int x1, int y1) {
+  int steep = abs(y1 - y0) > abs(x1 - x0);
+  int t;
+  
+  if (steep) {
+    t = x0; x0 = y0; y0 = t;
+    t = x1; x1 = y1; y1 = t;
+  }
+
+  if (x0 > x1) {
+    t = x0; x0 = x1; x1 = t;
+    t = y0; y0 = y1; y1 = t;
+  }
+
+  int dx, dy;
+  
+  dx = x1 - x0;
+  dy = abs(y1 - y0);
+
+  int err = dx / 2;
+  int ystep;
+
+  if (y0 < y1) {
+    ystep = 1;
+  } else {
+    ystep = -1;}
+
+  for (; x0<x1; x0++) {
+    if (steep) {
+      set_pixel(y0, x0);
+    } else {
+      set_pixel(x0, y0);
+    }
+    err -= dy;
+    if (err < 0) {
+      y0 += ystep;
+      err += dx;
+    }
+  }
+}
+
+void SSD1306::set_font(unsigned char *font, unsigned int width)
+{
+    _console_font_data = font;
+    _console_font_width = width;
+}
+
+void SSD1306::set_double_height_text(unsigned int double_height)
+{
+    _double_height_text = double_height;
+}
+
+void SSD1306::putc(unsigned char c)
+{
+    while (_cursor_x >= (128 / _console_font_width))
+    {
+        _cursor_x -= (128 / _console_font_width);
+        _cursor_y++;            
+    }
+
+    while (_cursor_y > 7)
+    {
+        scroll_up();            
+    }
+
+    switch (c)
+    {
+    case '\n':
+        _cursor_y++;
+        break;
+        
+    case '\r':
+        _cursor_x = 0;
+        break;
+        
+    case '\t':
+        _cursor_x = (_cursor_x + 4) % 4;
+        break;
+        
+    default:
+        for (int b = 0; b < _console_font_width; b++)
+        {
+            _screen[_cursor_x * _console_font_width + _cursor_y * 128 + b] = _console_font_data[(c - FONT_START) * _console_font_width + b];
+        }
+        
+        _cursor_x++;
+    }            
+}
+
+void SSD1306::scroll_up()
+{
+    for (int y = 1; y <= 7; y++)
+    {
+        for (int x = 0; x < 128; x++)
+        {
+            _screen[x + 128 * (y - 1)] = _screen[x + 128 * y];
+        }
+    }
+    
+    for (int x = 0; x < 128; x++)
+    {
+        _screen[x + 128 * 7] = 0;
+    }    
+
+    _cursor_y--;
+}
+
+void SSD1306::printf(const char *format, ...)
+{
+    static char buffer[128];
+    
+    va_list args;
+    va_start(args, format);
+    vsprintf(buffer, format, args);
+    va_end(args);
+    
+    char *c = (char *)&buffer;
+    while (*c != 0)
+    {
+        putc(*c++);
+    }
+}
+
+void SSD1306::clear()
+{
+    for (int i = 0; i < 1024; i++)
+        _screen[i] = 0;
+        
+    _cursor_x = 0;
+    _cursor_y = 0;
+}
+
+void SSD1306::_send_command(unsigned char code)
+{
+    _cs = 1;
+    _dc = 0;
+    _cs = 0;
+    _spi.write(code);
+    _cs = 1;
+}
+
+void SSD1306::_send_data(unsigned char value)
+{
+    _cs = 1;
+    _dc = 1;
+    _cs = 0;
+    _spi.write(value);
+    _cs = 1;
+}