README

This sample demonstrates the CSSD1309Display driver for SSD1309-controlled OLED
displays using the I2C interface (graphics mode). The SSD1309 is similar to the
SSD1306 but requires a mandatory hardware reset pin and uses an external VBAT
supply (no internal charge pump).

Before building you have to configure the program in kernel.h according to the
hardware of your display. You have to set the I2C address (typically 0x3C or
0x3D) and the GPIO number of the reset pin. The default configuration is:

Display		Raspberry Pi	Comment
		GPIO

SDA	<--	SDA	2	I2C data
SCL	<--	SCL	3	I2C clock
RST	<--		25	Reset (active low, active pull required)
VCC	<--	3.3V		Power supply
GND	<-->	GND

The sample program runs a series of graphics tests on the 128x64 display:
clearing, filling, drawing lines and rectangles, diagonal lines, a checkerboard
pattern, display on/off cycling, and a final center box. Progress is logged to
the screen and serial port (115200 baud).
