Raspberry Pi / Jetson - Tutorial da ecrã secundária OLED
Controlador principal da série Jetson
1. Diagrama de pinos GPIO
Use uma ecrã OLED de 0,91 polegadas para testar a função de comunicação I2C e conecte de acordo com a seguinte fiação:
Cuidado: não conecte incorretamente nem provoque curto-circuito nos pinos, pois erros podem causar danos ao hardware da placa principal!
2. Teste I2C
2.1. Instalar dependências
sudo apt install -y python3-pip
sudo pip3 install smbus
sudo pip3 install Adafruit_SSD13062.2, Dispositivo I2C
Durante o desenvolvimento normal, precisamos encontrar o barramento do dispositivo e o endereço do dispositivo onde o dispositivo I2C está montado.
(1) Consultar o barramento I2C
Inserir o seguinte comando no terminal pode listar todos os barramentos do dispositivo:
i2cdetect -l(2) Consultar o dispositivo I2C
Inserir o seguinte comando no terminal pode listar os dispositivos I2C sob o barramento especificado: o endereço I2C correspondente ao oled é 0x3c
i2cdetect -y -r *4. Verificar endereço IP e porta
Use ifconfig para ver o endereço IP e a porta
Altere o código de acordo com a porta real
3. Efeito do experimento
Crie o ficheiro Oled_i2c.py
sudo gedit Oled_i2c.pyCopie e cole o seguinte código
#!/usr/bin/env python3
# coding=utf-8
import time
import os
import sys
i2c_num = 7
if len(sys.argv) > 1:
if str(sys.argv[1]).isdigit():
i2c_num = int(sys.argv[1])
print("i2c_num=", i2c_num)
passwd = "juxi"
cmd_i2c = "sudo i2cdetect -y -r " + str(i2c_num)
os.system('echo %s | sudo -S %s' % (passwd, cmd_i2c))
import Adafruit_SSD1306 as SSD
from PIL import Image
from PIL import ImageDraw
from PIL import ImageFont
import subprocess
class Juxi_OLED:
def __init__(self, i2c_bus=1, debug=False):
self.__debug = debug
self.__i2c_bus = i2c_bus
self.__top = -2
self.__x = 0
self.__total_last = 0
self.__idle_last = 0
self.__str_CPU = "CPU:0%"
def __del__(self):
if self.__debug:
print("---OLED-DEL---")
# Initialize OLED, return True on success, False on failure
def begin(self):
try:
self.__oled = SSD.SSD1306_128_32(
rst=None, i2c_bus=self.__i2c_bus, gpio=1)
self.__oled.begin()
self.__oled.clear()
self.__oled.display()
self.__width = self.__oled.width
self.__height = self.__oled.height
self.__image = Image.new('1', (self.__width, self.__height))
self.__draw = ImageDraw.Draw(self.__image)
self.__font = ImageFont.truetype("DejaVuSansMono.ttf",8) # ImageFont.load_default()
if self.__debug:
print("---OLED begin ok!---")
return True
except:
# if self.__i2c_bus == 1:
# self.__i2c_bus = 8
# elif self.__i2c_bus == 8:
# self.__i2c_bus = 1
if self.__debug:
print("---OLED no found!---")
return False
# Clear the display. Refresh =True Refresh immediately, refresh=False refresh not
def clear(self, refresh=False):
self.__draw.rectangle(
(0, 0, self.__width, self.__height), outline=0, fill=0)
if refresh:
self.refresh()
# Add characters. Start_x Start_y indicates the starting point. Text is the character to be added
# Refresh =True Refresh immediately, refresh=False refresh not
def add_text(self, start_x, start_y, text, refresh=False):
if start_x > 128 or start_x < 0 or start_y < 0 or start_y > 32:
if self.__debug:
print("oled text: x, y input error!")
return
x = int(start_x + self.__x)
y = int(start_y + self.__top)
self.__draw.text((x, y), str(text), font=self.__font, fill=255)
if refresh:
self.refresh()
# line=[1, 4]
# Write a line of character text. Refresh =True Refresh immediately, refresh=False refresh not.
def add_line(self, text, line=1, refresh=False):
if line < 1 or line > 4:
if self.__debug:
print("oled line input error!")
return
y = int(8 * (line - 1))
self.add_text(0, y, text, refresh)
# Refresh the OLED to display the content
def refresh(self):
self.__oled.image(self.__image)
self.__oled.display()
# Read the CPU usage rate
def getCPULoadRate(self, index):
count = 10
if index == 0:
f1 = os.popen("cat /proc/stat", 'r')
stat1 = f1.readline()
data_1 = []
for i in range(count):
data_1.append(int(stat1.split(' ')[i+2]))
self.__total_last = data_1[0]+data_1[1]+data_1[2]+data_1[3] + \
data_1[4]+data_1[5]+data_1[6]+data_1[7]+data_1[8]+data_1[9]
self.__idle_last = data_1[3]
elif index == 4:
f2 = os.popen("cat /proc/stat", 'r')
stat2 = f2.readline()
data_2 = []
for i in range(count):
data_2.append(int(stat2.split(' ')[i+2]))
total_now = data_2[0]+data_2[1]+data_2[2]+data_2[3] + \
data_2[4]+data_2[5]+data_2[6]+data_2[7]+data_2[8]+data_2[9]
idle_now = data_2[3]
total = int(total_now - self.__total_last)
idle = int(idle_now - self.__idle_last)
usage = int(total - idle)
usageRate = int(float(usage / total) * 100)
self.__str_CPU = "CPU:" + str(usageRate) + "%"
self.__total_last = 0
self.__idle_last = 0
# if self.__debug:
# print(self.__str_CPU)
return self.__str_CPU
# Read system time
def getSystemTime(self):
cmd = "date +%H:%M:%S"
date_time = subprocess.check_output(cmd, shell=True)
str_Time = str(date_time).lstrip("b'")
str_Time = str_Time.rstrip("\\n'")
# print(date_time)
return str_Time
# Read the memory usage and total memory
def getUsagedRAM(self):
cmd = "free | awk 'NR==2{printf \"RAM:%2d%% -> %.1fGB \", 100*($2-$7)/$2, ($2/1048576.0)}'"
FreeRam = subprocess.check_output(cmd, shell=True)
str_FreeRam = str(FreeRam).lstrip("b'")
str_FreeRam = str_FreeRam.rstrip("'")
return str_FreeRam
# Read free memory/total memory
def getFreeRAM(self):
cmd = "free -h | awk 'NR==2{printf \"RAM: %.1f/%.1fGB \", $7,$2}'"
FreeRam = subprocess.check_output(cmd, shell=True)
str_FreeRam = str(FreeRam).lstrip("b'")
str_FreeRam = str_FreeRam.rstrip("'")
return str_FreeRam
# Read the TF card space usage/TOTAL TF card space
def getUsagedDisk(self):
cmd = "df -h | awk '$NF==\"/\"{printf \"SDC:%s -> %.1fGB\", $5, $2}'"
Disk = subprocess.check_output(cmd, shell=True)
str_Disk = str(Disk).lstrip("b'")
str_Disk = str_Disk.rstrip("'")
return str_Disk
# Read the free TF card space/total TF card space
def getFreeDisk(self):
cmd = "df -h | awk '$NF==\"/\"{printf \"Disk:%.1f/%.1fGB\", $4,$2}'"
Disk = subprocess.check_output(cmd, shell=True)
str_Disk = str(Disk).lstrip("b'")
str_Disk = str_Disk.rstrip("'")
return str_Disk
# Read the local IP address
def getLocalIP(self):
ip = os.popen(
"/sbin/ifconfig enP8p1s0 | grep 'inet' | awk '{print $2}'").read()
ip = ip[0: ip.find('\n')]
if(ip == ''):
ip = os.popen(
"/sbin/ifconfig wlP1p1s0 | grep 'inet' | awk '{print $2}'").read()
ip = ip[0: ip.find('\n')]
if(ip == ''):
ip = 'x.x.x.x'
if len(ip) > 15:
ip = 'x.x.x.x'
return ip
# Oled mainly runs functions that are called in a while loop and can be hot-pluggable
def main_program(self):
state = False
try:
cpu_index = 0
state = self.begin()
while state:
self.clear()
str_CPU = self.getCPULoadRate(cpu_index)
str_Time = self.getSystemTime()
if cpu_index == 0:
str_FreeRAM = self.getUsagedRAM()
str_Disk = self.getUsagedDisk()
str_IP = "IPA:" + self.getLocalIP()
self.add_text(0, 0, str_CPU)
self.add_text(50, 0, str_Time)
self.add_line(str_FreeRAM, 2)
self.add_line(str_Disk, 3)
self.add_line(str_IP, 4)
# Display image.
self.refresh()
cpu_index = cpu_index + 1
if cpu_index >= 5:
cpu_index = 0
time.sleep(.1)
except:
if self.__debug:
print("!!!---OLED refresh error---!!!")
pass
if __name__ == "__main__":
try:
oled = Juxi_OLED(i2c_num, debug=True)
while True:
oled.main_program()
time.sleep(2)
except KeyboardInterrupt:
oled.clear(True)
del oled
print(" Program closed! ")
passApós iniciar o programa, o ecrã OLED exibirá informações do sistema, como uso da CPU, hora do sistema e uso de memória:
Raspberry Pi, Orange Pi
1. Ativar a opção I2C
Entre nas configurações do sistema Raspberry Pi, selecione: Preferências → Configuração do Raspberry Pi → Interfaces → Encontre a opção I2C e ative-a; em seguida, o sistema reiniciará automaticamente. (Consulte a figura abaixo)
Se você estiver no modo de comando, pode inserir sudo raspi-config para ainda encontrar a opção de habilitar I2C e depois reiniciar o sistema.
2. Instalar os ficheiros da biblioteca I2C
sudo apt install -y python3-dev
sudo apt install -y python3-smbus i2c-tools
sudo apt install -y python3-pil
sudo apt install -y python3-pip
sudo apt install -y python3-setuptools
sudo apt install -y python3-rpi.gpio
sudo apt install -y python3-venvEstou a usar Python3. Após instalar a biblioteca I2C, use o comando i2cdetect para verificar se o módulo de exibição é reconhecido
i2cdetect -y 1Indica que o dispositivo foi detectado no endereço "0x3c" (como mostrado abaixo). O padrão para este tipo de dispositivo é um endereço hexadecimal.
3. Configuração do ficheiro de fonte
O código usa a fonte DejaVuSansMono.ttf:
sudo apt-get install -y fonts-dejavu-coreou modifique o código para usar uma fonte já disponível no sistema (como ImageFont.load_default())
4. Configuração de permissões
Garanta que as permissões do ficheiro de dispositivo I2C estejam corretas:
sudo chmod a+rw /dev/i2c-* # Temporary effect, permanent effect requires configuration of udev rules5. Verificar endereço IP e porta
Use ifconfig para ver o endereço IP e a porta reais
# (如未安装net-tools)sudo apt install net-tools
ifconfigAltere o conteúdo das duas áreas destacadas a seguir no código de acordo com a porta real
6. Criar o ficheiro Oled_i2c.py
Crie o ficheiro Oled_i2c.py no diretório Home
# (如未安装gedit) sudo apt install gedit
sudo gedit Oled_i2c.pyCopie o código a seguir, cole-o no ficheiro, guarde e feche
#!/usr/bin/env python3
# coding=utf-8
import time
import os
import sys
i2c_num = 7
if len(sys.argv) > 1:
if str(sys.argv[1]).isdigit():
i2c_num = int(sys.argv[1])
print("i2c_num=", i2c_num)
passwd = "juxi"
cmd_i2c = "sudo i2cdetect -y -r " + str(i2c_num)
os.system('echo %s | sudo -S %s' % (passwd, cmd_i2c))
import Adafruit_SSD1306 as SSD
from PIL import Image
from PIL import ImageDraw
from PIL import ImageFont
import subprocess
class Juxi_OLED:
def __init__(self, i2c_bus=1, debug=False):
self.__debug = debug
self.__i2c_bus = i2c_bus
self.__top = -2
self.__x = 0
self.__total_last = 0
self.__idle_last = 0
self.__str_CPU = "CPU:0%"
def __del__(self):
if self.__debug:
print("---OLED-DEL---")
# 初始化OLED,成功返回:True,失败返回:False
# Initialize OLED, return True on success, False on failure
def begin(self):
try:
self.__oled = SSD.SSD1306_128_32(
rst=None, i2c_bus=self.__i2c_bus, gpio=1)
self.__oled.begin()
self.__oled.clear()
self.__oled.display()
self.__width = self.__oled.width
self.__height = self.__oled.height
self.__image = Image.new('1', (self.__width, self.__height))
self.__draw = ImageDraw.Draw(self.__image)
self.__font = ImageFont.truetype("DejaVuSansMono.ttf",8) # ImageFont.load_default()
if self.__debug:
print("---OLED begin ok!---")
return True
except:
# if self.__i2c_bus == 1:
# self.__i2c_bus = 8
# elif self.__i2c_bus == 8:
# self.__i2c_bus = 1
if self.__debug:
print("---OLED no found!---")
return False
# 清除显示。refresh=True立即刷新,refresh=False不刷新。
# Clear the display. Refresh =True Refresh immediately, refresh=False refresh not
def clear(self, refresh=False):
self.__draw.rectangle(
(0, 0, self.__width, self.__height), outline=0, fill=0)
if refresh:
self.refresh()
# 增加字符。start_x start_y表示开始的点。text是要增加的字符。
# refresh=True立即刷新,refresh=False不刷新。
# Add characters. Start_x Start_y indicates the starting point. Text is the character to be added
# Refresh =True Refresh immediately, refresh=False refresh not
def add_text(self, start_x, start_y, text, refresh=False):
if start_x > 128 or start_x < 0 or start_y < 0 or start_y > 32:
if self.__debug:
print("oled text: x, y input error!")
return
x = int(start_x + self.__x)
y = int(start_y + self.__top)
self.__draw.text((x, y), str(text), font=self.__font, fill=255)
if refresh:
self.refresh()
# 写入一行字符text。refresh=True立即刷新,refresh=False不刷新。
# line=[1, 4]
# Write a line of character text. Refresh =True Refresh immediately, refresh=False refresh not.
def add_line(self, text, line=1, refresh=False):
if line < 1 or line > 4:
if self.__debug:
print("oled line input error!")
return
y = int(8 * (line - 1))
self.add_text(0, y, text, refresh)
# 刷新OLED,显示内容
# Refresh the OLED to display the content
def refresh(self):
self.__oled.image(self.__image)
self.__oled.display()
# 读取CPU占用率
# Read the CPU usage rate
def getCPULoadRate(self, index):
count = 10
if index == 0:
f1 = os.popen("cat /proc/stat", 'r')
stat1 = f1.readline()
data_1 = []
for i in range(count):
data_1.append(int(stat1.split(' ')[i+2]))
self.__total_last = data_1[0]+data_1[1]+data_1[2]+data_1[3] + \
data_1[4]+data_1[5]+data_1[6]+data_1[7]+data_1[8]+data_1[9]
self.__idle_last = data_1[3]
elif index == 4:
f2 = os.popen("cat /proc/stat", 'r')
stat2 = f2.readline()
data_2 = []
for i in range(count):
data_2.append(int(stat2.split(' ')[i+2]))
total_now = data_2[0]+data_2[1]+data_2[2]+data_2[3] + \
data_2[4]+data_2[5]+data_2[6]+data_2[7]+data_2[8]+data_2[9]
idle_now = data_2[3]
total = int(total_now - self.__total_last)
idle = int(idle_now - self.__idle_last)
usage = int(total - idle)
usageRate = int(float(usage / total) * 100)
self.__str_CPU = "CPU:" + str(usageRate) + "%"
self.__total_last = 0
self.__idle_last = 0
# if self.__debug:
# print(self.__str_CPU)
return self.__str_CPU
# 读取系统时间
# Read system time
def getSystemTime(self):
cmd = "date +%H:%M:%S"
date_time = subprocess.check_output(cmd, shell=True)
str_Time = str(date_time).lstrip("b'")
str_Time = str_Time.rstrip("\\n'")
# print(date_time)
return str_Time
# 读取内存占用率 和 总内存
# Read the memory usage and total memory
def getUsagedRAM(self):
cmd = "free | awk 'NR==2{printf \"RAM:%2d%% -> %.1fGB \", 100*($2-$7)/$2, ($2/1048576.0)}'"
FreeRam = subprocess.check_output(cmd, shell=True)
str_FreeRam = str(FreeRam).lstrip("b'")
str_FreeRam = str_FreeRam.rstrip("'")
return str_FreeRam
# 读取空闲的内存 / 总内存
# Read free memory/total memory
def getFreeRAM(self):
cmd = "free -h | awk 'NR==2{printf \"RAM: %.1f/%.1fGB \", $7,$2}'"
FreeRam = subprocess.check_output(cmd, shell=True)
str_FreeRam = str(FreeRam).lstrip("b'")
str_FreeRam = str_FreeRam.rstrip("'")
return str_FreeRam
# 读取TF卡空间占用率 / TF卡总空间
# Read the TF card space usage/TOTAL TF card space
def getUsagedDisk(self):
cmd = "df -h | awk '$NF==\"/\"{printf \"SDC:%s -> %.1fGB\", $5, $2}'"
Disk = subprocess.check_output(cmd, shell=True)
str_Disk = str(Disk).lstrip("b'")
str_Disk = str_Disk.rstrip("'")
return str_Disk
# 读取空闲的TF卡空间 / TF卡总空间
# Read the free TF card space/total TF card space
def getFreeDisk(self):
cmd = "df -h | awk '$NF==\"/\"{printf \"Disk:%.1f/%.1fGB\", $4,$2}'"
Disk = subprocess.check_output(cmd, shell=True)
str_Disk = str(Disk).lstrip("b'")
str_Disk = str_Disk.rstrip("'")
return str_Disk
# 获取本机IP
# Read the local IP address
def getLocalIP(self):
ip = os.popen(
"/sbin/ifconfig enP8p1s0 | grep 'inet' | awk '{print $2}'").read()
ip = ip[0: ip.find('\n')]
if(ip == ''):
ip = os.popen(
"/sbin/ifconfig wlP1p1s0 | grep 'inet' | awk '{print $2}'").read()
ip = ip[0: ip.find('\n')]
if(ip == ''):
ip = 'x.x.x.x'
if len(ip) > 15:
ip = 'x.x.x.x'
return ip
# oled主要运行函数,在while循环里调用,可实现热插拔功能。
# Oled mainly runs functions that are called in a while loop and can be hot-pluggable
def main_program(self):
state = False
try:
cpu_index = 0
state = self.begin()
while state:
self.clear()
str_CPU = self.getCPULoadRate(cpu_index)
str_Time = self.getSystemTime()
if cpu_index == 0:
str_FreeRAM = self.getUsagedRAM()
str_Disk = self.getUsagedDisk()
str_IP = "IPA:" + self.getLocalIP()
self.add_text(0, 0, str_CPU)
self.add_text(50, 0, str_Time)
self.add_line(str_FreeRAM, 2)
self.add_line(str_Disk, 3)
self.add_line(str_IP, 4)
# Display image.
self.refresh()
cpu_index = cpu_index + 1
if cpu_index >= 5:
cpu_index = 0
time.sleep(.1)
except:
if self.__debug:
print("!!!---OLED refresh error---!!!")
pass
if __name__ == "__main__":
try:
oled = Juxi_OLED(i2c_num, debug=True)
while True:
oled.main_program()
time.sleep(2)
except KeyboardInterrupt:
oled.clear(True)
del oled
print(" Program closed! ")
pass7. Criar um ambiente virtual
# 安装虚拟环境工具(如果未安装)sudo apt-get install -y python3-venv
# 创建虚拟环境
python3 -m venv oled_env
# 激活虚拟环境source oled_env/bin/activate # 激活后命令行前会显示 (oled_env)# 在虚拟环境中安装依赖
# 使用阿里云镜像安装
pip install Adafruit_SSD1306 -i https://mirrors.aliyun.com/pypi/simple/
# 同时安装 pillow(依赖库)
pip install pillow -i https://mirrors.aliyun.com/pypi/simple/
# 运行代码(需在虚拟环境中)
# 进入到对应的simple文件夹下
cd /home/pi/oled-screen/luma.examples/examples
python3 oled_i2c.py # 默认总线 7
# 或指定总线(如总线 1)
python3 oled_i2c.py 1
#若提示权限错误,检查 sudo 配置或 I2C 设备权限Exemplo do repositório oficial
A Juxi Technology fornece código de driver open source para o ecrã OLED: GitHub
Exemplo de driver I2C
sudo apt install -y python3-pip
sudo pip3 install smbus Adafruit_SSD1306import Adafruit_SSD1306
from PIL import Image, ImageDraw, ImageFont
# 初始化 OLED (128x32)
disp = Adafruit_SSD1306.SSD1306_128_32(rst=None)
disp.begin()
disp.clear()
disp.display()
# 绘制文字
image = Image.new('1', (disp.width, disp.height))
draw = ImageDraw.Draw(image)
draw.text((0, 0), 'Hello Juxi!', font=ImageFont.load_default(), fill=255)
disp.image(image)
disp.display()
