In the example code, you will need to set the size of your display and the pins used for the I2C connections for SDA and SCL. There is also a control for rotating the screen.
If the display does not work for larger displays, try increasing the size of the buffer eg.
static uint8_t ucBackBuffer[2048];
The size is limited the amount of RAM onboard your Arduino. You may need to turn off the buffer completely (at the cost of display speed) if running on a micro device.
Supports any number of simultaneous displays of any type (mix and match)
Optionally detect the display address and type (I2C only)
Drive displays from I2C, SPI or any 2 GPIO pins (virtual I2C)
5 sizes of fixed fonts (6x8, 8x8, 12x16, 16x16, 16x32)
Deferred rendering allows preparing a back buffer, then displaying it (usually faster)
Text scrolling features (vertical and horizontal)
Text cursor position with optional line wrap
a function to load a Windows BMP file
Pixel drawing on SH1106/7 without needing backing RAM
Optimized Bresenham line drawing
Optimized Bresenham outline and filled ellipse drawing
Optimized outline and filled rectangle drawing
Optional backing RAM for drawing pixels for systems with enough RAM
16x16 Tile/Sprite drawing at any angle.
Run full frame animations at high frame rates with a simple API
Light enough to run on an ATtiny85
Example
Demonstrates basic functionality and compared buffered / non-buffered write speeds
//
// OneBitDisplay library simple demo
//
// Demonstrates how to initialize and use a few functions of the library
// If your MCU has enough RAM, enable the backbuffer to see a demonstration
// of the speed difference between drawing directly on the display versus
// deferred rendering, followed by a "dump" of the memory to the display
//
#include <OneBitDisplay.h>
// if your system doesn't have enough RAM for a back buffer, comment out
// this line (e.g. ATtiny85)
#define USE_BACKBUFFER
#ifdef USE_BACKBUFFER
static uint8_t ucBackBuffer[2048];
#else
static uint8_t *ucBackBuffer = NULL;
#endif
// Use -1 for the Wire library default pins
// or specify the pin numbers to use with the Wire library or bit banging on any GPIO pins
// These are the pin numbers for the M5Stack Atom Grove port I2C (reversed SDA/SCL for straight through wiring)
#define SDA_PIN 20
#define SCL_PIN 21
// Set this to -1 to disable or the GPIO pin number connected to the reset
// line of your display if it requires an external reset
#define RESET_PIN -1
// let OneBitDisplay figure out the display address
#define OLED_ADDR -1
// don't rotate the display
#define FLIP180 1
// don't invert the display
#define INVERT 0
// Bit-Bang the I2C bus
#define USE_HW_I2C 1
// Change these if you're using a different OLED display
#define MY_OLED OLED_128x128
#define OLED_WIDTH 128
#define OLED_HEIGHT 128
//#define MY_OLED OLED_64x32
//#define OLED_WIDTH 64
//#define OLED_HEIGHT 32
OBDISP obd;
void setup() {
int rc;
// The I2C SDA/SCL pins set to -1 means to use the default Wire library
// If pins were specified, they would be bit-banged in software
// This isn't inferior to hw I2C and in fact allows you to go faster on certain CPUs
// The reset pin is optional and I've only seen it needed on larger OLEDs (2.4")
// that can be configured as either SPI or I2C
//
// obdI2CInit(OBDISP *, type, oled_addr, rotate180, invert, bWire, SDA_PIN, SCL_PIN, RESET_PIN, speed)
rc = obdI2CInit(&obd, MY_OLED, OLED_ADDR, FLIP180, INVERT, USE_HW_I2C, SDA_PIN, SCL_PIN, RESET_PIN, 800000L); // use standard I2C bus at 400Khz
if (rc != OLED_NOT_FOUND)
{
char *msgs[] = {(char *)"SSD1306 @ 0x3C", (char *)"SSD1306 @ 0x3D",(char *)"SH1106 @ 0x3C",(char *)"SH1106 @ 0x3D"};
obdFill(&obd, 0, 1);
obdWriteString(&obd, 0,0,0,msgs[rc], FONT_8x8, 0, 1);
obdSetBackBuffer(&obd, ucBackBuffer);
delay(2000);
}
} /* setup() */
void loop() {
// put your main code here, to run repeatedly:
int i, x, y;
char szTemp[32];
unsigned long ms;
obdFill(&obd, 0x0, 1);
obdWriteString(&obd, 0,28,0,(char *)"OLED Demo", FONT_8x8, 0, 1);
obdWriteString(&obd, 0,0,1,(char *)"Written by Larry Bank", FONT_6x8, 1, 1);
obdWriteString(&obd, 0,0,3,(char *)"**Demo**", FONT_16x32, 0, 1);
delay(2000);
// Pixel and line functions won't work without a back buffer
#ifdef USE_BACKBUFFER
obdFill(&obd, 0, 1);
obdWriteString(&obd, 0,0,0,(char *)"Backbuffer Test", FONT_8x8,0,1);
obdWriteString(&obd, 0,0,1,(char *)"3000 Random dots", FONT_8x8,0,1);
delay(2000);
obdFill(&obd, 0,1);
ms = millis();
for (i=0; i<3000; i++)
{
x = random(OLED_WIDTH);
y = random(OLED_HEIGHT);
obdSetPixel(&obd, x, y, 1, 1);
}
ms = millis() - ms;
sprintf(szTemp, "%dms", (int)ms);
obdWriteString(&obd, 0,0,0,szTemp, FONT_8x8, 0, 1);
obdWriteString(&obd, 0,0,1,(char *)"Without backbuffer", FONT_6x8,0,1);
delay(2000);
obdFill(&obd, 0,1);
ms = millis();
for (i=0; i<3000; i++)
{
x = random(OLED_WIDTH);
y = random(OLED_HEIGHT);
obdSetPixel(&obd, x, y, 1, 0);
}
obdDumpBuffer(&obd, NULL);
ms = millis() - ms;
sprintf(szTemp, "%dms", (int)ms);
obdWriteString(&obd, 0,0,0,szTemp, FONT_8x8, 0, 1);
obdWriteString(&obd, 0,0,1,(char *)"With backbuffer", FONT_6x8,0,1);
delay(2000);
obdFill(&obd, 0, 1);
obdWriteString(&obd, 0,0,0,(char *)"Backbuffer Test", FONT_8x8,0,1);
obdWriteString(&obd, 0,0,1,(char *)"96 lines", FONT_8x8,0,1);
delay(2000);
ms = millis();
for (x=0; x<OLED_WIDTH-1; x+=2)
{
obdDrawLine(&obd, x, 0, OLED_WIDTH-x, OLED_HEIGHT-1, 1, 1);
}
for (y=0; y<OLED_HEIGHT-1; y+=2)
{
obdDrawLine(&obd, OLED_WIDTH-1,y, 0,OLED_HEIGHT-1-y, 1, 1);
}
ms = millis() - ms;
sprintf(szTemp, "%dms", (int)ms);
obdWriteString(&obd, 0,0,0,szTemp, FONT_8x8, 0, 1);
obdWriteString(&obd, 0,0,1,(char *)"Without backbuffer", FONT_6x8,0,1);
delay(2000);
obdFill(&obd, 0,1);
ms = millis();
for (x=0; x<OLED_WIDTH-1; x+=2)
{
obdDrawLine(&obd, x, 0, OLED_WIDTH-1-x, OLED_HEIGHT-1, 1, 0);
}
for (y=0; y<OLED_HEIGHT-1; y+=2)
{
obdDrawLine(&obd, OLED_WIDTH-1,y, 0,OLED_HEIGHT-1-y, 1, 0);
}
obdDumpBuffer(&obd, ucBackBuffer);
ms = millis() - ms;
sprintf(szTemp, "%dms", (int)ms);
obdWriteString(&obd, 0,0,0,szTemp, FONT_8x8, 0, 1);
obdWriteString(&obd, 0,0,1,(char *)"With backbuffer", FONT_6x8,0,1);
delay(2000);
#endif
} /* loop() */
