# 點屏之SPI OLED 這里使用常見的ssd1306驅動芯片的oled屏。 ssd1306支持6800,8080,4線SPI，3線SPI，I2C接口。 驅動手冊在此下載：https://pan.baidu.com/s/1pLZchuF 這里以4線SPI為例驅動。 ## 硬件連接 |OLED屏|LicheePi Zero| |-----|-----| |GND|GND| |VCC|3V3| |D0|SPI SCK| |D1|SPI MOSI| |RES|3V3| |DC|PB5| |CS|SPI CS| ## 設備樹修改 這里速率使用1M即可，太高會無法響應。 ~~~ &spi0 { status = "okay"; ssd1306@0 { compatible = "solomon,ssd1306"; reg = <0>; spi-max-frequency = <1000000>; rotate = <0>; bgr; fps = <30>; buswidth = <8>; reset-gpios = <&pio 1 7 GPIO_ACTIVE_LOW>; dc-gpios = <&pio 1 5 GPIO_ACTIVE_LOW>; debug = <0>; }; }; ~~~ ## 編譯下載 在menuconfig中選中staging driver 下的fbtft的ssd1306驅動，編譯入內核。 ## 顯示效果 圖片顯示：  視頻播放： http://v.youku.com/v_show/id_XMzM5NDU4MjI0NA==.html ## 驅動走讀 ~~~ /* Set Display OFF */ write_reg(par, 0xAE); /* Set Display Clock Divide Ratio/ Oscillator Frequency */ write_reg(par, 0xD5); //默認使用內部rc振蕩電路，頻率在370KHz左右 write_reg(par, 0x80); //幀率 370k/D/54/64=107 fps /* Set Multiplex Ratio */ write_reg(par, 0xA8); if (par->info->var.yres == 64) write_reg(par, 0x3F); else if (par->info->var.yres == 48) write_reg(par, 0x2F); else write_reg(par, 0x1F); /* Set Display Offset */ write_reg(par, 0xD3); write_reg(par, 0x0); /* Set Display Start Line */ write_reg(par, 0x40 | 0x0); /* Charge Pump Setting */ write_reg(par, 0x8D); /* A[2] = 1b, Enable charge pump during display on */ write_reg(par, 0x14); /* Set Memory Addressing Mode */ write_reg(par, 0x20); /* Vertical addressing mode */ write_reg(par, 0x01); /* Set Segment Re-map */ /* column address 127 is mapped to SEG0 */ write_reg(par, 0xA0 | 0x1); /* Set COM Output Scan Direction */ /* remapped mode. Scan from COM[N-1] to COM0 */ write_reg(par, 0xC8); /* Set COM Pins Hardware Configuration */ write_reg(par, 0xDA); if (par->info->var.yres == 64) /* A[4]=1b, Alternative COM pin configuration */ write_reg(par, 0x12); else if (par->info->var.yres == 48) /* A[4]=1b, Alternative COM pin configuration */ write_reg(par, 0x12); else /* A[4]=0b, Sequential COM pin configuration */ write_reg(par, 0x02); /* Set Pre-charge Period */ write_reg(par, 0xD9); write_reg(par, 0xF1); /* Set VCOMH Deselect Level */ write_reg(par, 0xDB); /* according to the datasheet, this value is out of bounds */ write_reg(par, 0x40); /* Entire Display ON */ /* Resume to RAM content display. Output follows RAM content */ write_reg(par, 0xA4); /* Set Normal Display * 0 in RAM: OFF in display panel * 1 in RAM: ON in display panel */ write_reg(par, 0xA6); /* Set Display ON */ write_reg(par, 0xAF); ~~~