如何把一个OLED屏幕用在树莓派上（希望能帮到大家）

电源

如何把一个OLED屏幕用在树莓派上（朋友力作）Raspberry Pi B使用SPI接口OLED(SSD1306)显示屏：基于python和c

Nova Raspberry Pi

一　首先介绍使用python来驱动这个SPI接口的OLED

(1)　OLED与树莓派连线

树莓派自带的26个排针接口里面就有一组SPI接口：GPIO9(MISO) ，GPIO10(MOSI)， GPIO11(SCL)。

然后看一下我使用的OLED的接口(注意，OLED的驱动芯片必须是SSD1306)：

分别是GND VCC D0 D1 RST DC CS

各个口的功能与树莓派的IO口连线分别如下：

GND接树莓派的GND, VCC接树莓派的3v3 POWER口，就是电源口，不要接到5V

CS是SPI的片选口，可以多组SPI同时使用，这里接树莓派的GPIO8(CE0)口，第24个管脚

DC口是数据与命令选择口，这里接到第13管脚，对于R1版本的树莓派就是GPIO21，我的是R2版本的(内存512MB)，对应的是GPIO27

RST是复位口，这里接到GPIO17也就是11管脚

D1(MOSI)口，接到树莓派的GPIO10(MOSI)口，也就是21管脚

D0(SCLK)口，接到树莓派的GPIO11(SCLK)口，也就是23管脚

(2) 打开树莓派的spi口

树莓派默认的SPI和I2C口都是被禁用的，使用之前必须先打开

首先是ssh登陆到树莓派上：

1.vi /etc/modprobe.d/raspi-blacklist.conf
2.#blacklist spi-bcm2708 #使用井号注释掉这行
3.blacklist i2c-bcm2708 #如果要使用i2c就注释掉这行

保存后重启树莓派，sudo reboot，这样就会打开树莓派的spi口，具体你可以在/dev目录下看到两个文件：spidev0.0　spidev0.1，对应于GPIO口上的SPI口，0和1表示片选管脚CE0和CE1

(3) 使用python开始驱动SPI口的OLED

还是用ssh登陆到树莓派上，安装一些并要的软件，如果因为网络安装不成功，请重复该命令：

sudo apt-get update

sudo apt-get install build-essential python-dev python-pip

sudo pip install RPi.GPIO

sudo apt-get install python-imaging python-smbus

sudo apt-get install git

#clone 下国外友人提供的python库

git clone https://github.com/adafruit/Adafruit_Python_SSD1306.git

cd Adafruit_Python_SSD1306

sudo python setup.py install

下面就可以使用python来驱动这个OLED了：

新建个python文件：spioled.py

import time
import Adafruit_GPIO.SPI as SPI
import Adafruit_SSD1306
import Image
import ImageDraw
import ImageFont

# Raspberry Pi pin configuration:
RST = 17
# Note the following are only used with SPI:
DC = 27
SPI_PORT = 0
SPI_DEVICE = 0

# 128x64 display with hardware SPI:
disp = Adafruit_SSD1306.SSD1306_128_64(rst=RST, dc=DC, spi=SPI.SpiDev(SPI_PORT, SPI_DEVICE, max_speed_hz=8000000))

# Initialize library.
disp.begin()

# Clear display.
disp.clear()
disp.display()

# Create blank image for drawing.
# Make sure to create image with mode '1' for 1-bit color.
width = disp.width
height = disp.height
image = Image.new('1', (width, height))

# Get drawing object to draw on image.
draw = ImageDraw.Draw(image)

# Draw a black filled box to clear the image.
draw.rectangle((0,0,width,height), outline=0, fill=0)

# Draw some shapes.
# First define some constants to allow easy resizing of shapes.
padding = 2
shape_width = 20
top = padding
bottom = height-padding
# Move left to right keeping track of the current x position for drawing shapes.
x = padding
# Draw an ellipse.
draw.ellipse((x, top , x+shape_width, bottom), outline=255, fill=0)
x += shape_width+padding
# Draw a rectangle.
draw.rectangle((x, top, x+shape_width, bottom), outline=255, fill=0)
x += shape_width+padding
# Draw a triangle.
draw.polygon([(x, bottom), (x+shape_width/2, top), (x+shape_width, bottom)], outline=255, fill=0)
x += shape_width+padding
# Draw an X.
draw.line((x, bottom, x+shape_width, top), fill=255)
draw.line((x, top, x+shape_width, bottom), fill=255)
x += shape_width+padding

# Load default font.
font = ImageFont.load_default()

# Alternatively load a TTF font.
# Some other nice fonts to try: http://www.dafont.com/bitmap.php
#font = ImageFont.truetype('Minecraftia.ttf', 8)

# Write two lines of text.
draw.text((x, top), 'Hello', font=font, fill=255)
draw.text((x, top+20), 'World!', font=font, fill=255)

# Display image.
disp.image(image)
disp.display()

运行该程序,sudo python spioled.py

就会发现显示屏开始有显示了。

然后呢，我又改写了一个程序，只输出字符：

import time
import Adafruit_GPIO.SPI as SPI
import Adafruit_SSD1306
import Image
import ImageDraw
import ImageFont

# Raspberry Pi pin configuration:
RST = 17
# Note the following are only used with SPI:
DC = 27
SPI_PORT = 0
SPI_DEVICE = 0

# 128x64 display with hardware SPI:
disp = Adafruit_SSD1306.SSD1306_128_64(rst=RST, dc=DC, spi=SPI.SpiDev(SPI_PORT, SPI_DEVICE, max_speed_hz=8000000))

# Initialize library.
disp.begin()

# Clear display.
disp.clear()
disp.display()

# Create blank image for drawing.
# Make sure to create image with mode '1' for 1-bit color.
width = disp.width
height = disp.height
image = Image.new('1', (width, height))

# Get drawing object to draw on image.
draw = ImageDraw.Draw(image)

# Draw a black filled box to clear the image.
draw.rectangle((0,0,width,height), outline=0, fill=0)

# Draw some shapes.
# First define some constants to allow easy resizing of shapes.
padding = 1
top = padding
x = padding
# Load default font.
font = ImageFont.load_default()

# Alternatively load a TTF font.
# Some other nice fonts to try: http://www.dafont.com/bitmap.php
#font = ImageFont.truetype('Minecraftia.ttf', 8)

# Write two lines of text.
draw.text((x, top), 'This is first line', font=font, fill=255)
draw.text((x, top+10), 'This is second line', font=font, fill=255)
draw.text((x, top+20), 'This is third line', font=font, fill=255)
draw.text((x, top+30), 'This is fourth line', font=font, fill=255)
draw.text((x, top+40), 'This is fifth line', font=font, fill=255)
draw.text((x, top+50), 'This is last line', font=font, fill=255)

# Display image.
disp.image(image)
disp.display()