Jonathan Gaul / SSD1306

A buffered display driver for the SSD1306 OLED controller. Please note that this is a work-in-progress; only very rudimentary drawing support is provided.

Dependents:   Projetv0 greenhouse_proj ProjetLong_Serre_V3 ProjetLong_Serre_V3_1 ... more

Example of use:

#include "mbed.h"

#include "ssd1306.h"
#include "standard_font.h"
#include "bold_font.h"

SSD1306 oled(p8 /* cs */, p9 /* reset */, p14 /* dc */,
             p13 /* clock */, p11 /* data */);

int main()
{
    oled.initialise();
    oled.clear();
    oled.set_contrast(255); // max contrast

    oled.set_font(bold_font, 8);
    oled.printf("Heading\r\n");

    oled.set_font(standard_font, 6);
    oled.printf("Hello World!\r\n");
    oled.printf("Some more text here...");

    oled.update();

    while (1)
    {
        wait(2);
        oled.scroll_up();
        oled.update();
    }
}

Diff: ssd1306.cpp

Revision:
3:1d9df877c90a
Parent:
2:e479b0296757
--- a/ssd1306.cpp	Tue Feb 05 21:21:22 2013 +0000
+++ b/ssd1306.cpp	Sat Feb 09 16:43:49 2013 +0000
@@ -2,11 +2,15 @@
 #include "mbed.h"
 #include "ssd1306.h"
 
+#include <stdarg.h>
+
 SSD1306::SSD1306(PinName cs, PinName rs, PinName dc, PinName clk, PinName data)
     : _spi(data, NC, clk), 
       _cs(cs), 
       _reset(rs), 
-      _dc(dc)
+      _dc(dc),
+      _cursor_x(0),
+      _cursor_y(0)
 {
 }
 
@@ -211,7 +215,7 @@
     set_display_offset(0);    
     set_display_start_line(0);  
     set_charge_pump_enable(1);    
-    set_memory_addressing_mode(0); // horizontal addressing mode
+    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);
@@ -294,32 +298,95 @@
   }
 }
 
-void SSD1306::draw_string(char *font, int x, int y, const char *string)
+void SSD1306::set_font(unsigned char *font, unsigned int width)
 {
-    _cursor_x = x;
-    _cursor_y = y;
-    
-    for (int i = 0; i < strlen(string); i++) 
-        draw_char(font, _cursor_x, _cursor_y, string[i]);
+    _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::draw_char(char *font, int x, int y, char c)
+void SSD1306::putc(unsigned char c)
 {
-    int height = font[FONT_HEIGHT_OFFSET];
-    int max_width = font[FONT_SIZE_OFFSET];
-    int char_size_bytes = max_width * height + 1;
-    int char_width = font[(c - FONT_START) * char_size_bytes + FONT_DATA_OFFSET];
-    for (int i = 0; i < char_width; i++)
-        _screen[(x + i) + (y * SSD1306_LCDWIDTH)] = font[(c - FONT_START) * (char_size_bytes) + i + FONT_DATA_OFFSET + 1];
+    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];
+        }
+    }
     
-    _cursor_x = x + char_width;
-    _cursor_y = 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)