ssd1306: Comment initialization sequence (aa84611c) · Commits · derf / multipass

include/driver/ssd1306.h

+76 −3

Original line number	Diff line number	Diff line
		@@ -38,28 +38,101 @@ class SSD1306 {
		unsigned char txbuf[130];
		unsigned char rxbuf[2];

		/*
		* Adjust both SSD1306_SET_SEG_REMAP and SSD1306_SET_COM_OUT_DIR for
		* 180° rotation.
		*/
		const unsigned char init1[6] = {
		// Turn off power for configuration
		SSD1306_SET_DISP \| 0x00,

		/*
		* Enable Horizontal Addressing Mode. Assuming image data is
		* {A, B, C, ...}, each byte corresponds to a 1x8 column, starting
		* at the top left corner and proceeding to the right and then down:
		*
		* A7 B7 C7 ...
		* .. .. .. ...
		* A0 B0 C0 ...
		*/
		SSD1306_SET_MEM_ADDR, 0x00,

		// RAM line 0 == display line 0
		SSD1306_SET_DISP_START_LINE \| 0x00,

		/*
		* Horizontal Layout: Column 127 is SEG0.
		* This depends on the connection between SSD1306 and OLED.
		* Use 0x00 if your content is horizontally mirrored.
		*/
		SSD1306_SET_SEG_REMAP \| 0x01,

		/*
		* Multiplex ratio is the number of display lines
		* (i.e., the display height)
		*/
		SSD1306_SET_MUX_RATIO
		};
		// height

		// height-1 sent by init()

		const unsigned char init2[4] = {
		/*
		* Vertical Layout: Scan from COM63 to COM0.
		* This depends on the connection between SSD1306 and OLED.
		* Use 0x00 if your content is vertically mirrored.
		*/
		SSD1306_SET_COM_OUT_DIR \| 0x08,

		// No vertical display offset
		SSD1306_SET_DISP_OFFSET, 0x00,

		/*
		* COM PIN layout depends on display height and type. See
		* datasheet and init().
		*/
		SSD1306_SET_COM_PIN_CFG
		};

		// height == 32? 0x02 : 0x12

		const unsigned char init3[13] = {
		/*
		* Set clock to recommended values: 370 kHz (bits 7..4),
		* no divider (bits 3..0). Increase divider for glitchy effects.
		* The datasheet is unclear on the clock frequency range.
		*/
		SSD1306_SET_DISP_CLK_DIV, 0x80,
		SSD1306_SET_PRECHARGE, 0xf1,

		/*
		* Set line (multiplex) precharge times.
		* phase 1 (discharge pixels to avoid effects from the previous line): 8 cycles
		* phase 2 (charge pixels for next line): 8 cycles
		* decrease phase 1 time for glitchy effects.
		*/
		SSD1306_SET_PRECHARGE, 0x88,

		/*
		* VCOM deselect level. Unknown.
		* 0x00: ~0.65 VCC
		* 0x20: ~0.77 VCC
		* 0x30: ~0.85 VCC
		*/
		SSD1306_SET_VCOM_DESEL, 0x30,

		// start with medium contrast
		SSD1306_SET_CONTRAST, 0x7f,

		// display content == RAM content
		SSD1306_SET_ENTIRE_ON,
		SSD1306_SET_NORM_INV,

		// regular (uninverted) display
		SSD1306_SET_NORM_INV \| 0x00,

		// Enable charge pump (provide power to the display)
		SSD1306_SET_CHARGE_PUMP, 0x14,

		// turn on display
		SSD1306_SET_DISP \| 0x01
		};

src/driver/ssd1306.cc

+1 −0

Original line number	Diff line number	Diff line
		@@ -20,6 +20,7 @@ void SSD1306::init()
		for (i = 0; i < sizeof(init1); i++) {
		writeCommand(init1[i]);
		}
		// set multiplex ratio (i.e., number of rows)
		writeCommand(height - 1);
		for (i = 0; i < sizeof(init2); i++) {
		writeCommand(init2[i]);

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