Tutoriel écran OLED secondaire Raspberry Pi / Jetson
Série Jetson
1. Brochage GPIO
Testez la communication I2C avec l'écran OLED 0,91 pouce. Connectez-le comme suit :
Attention : ne faites pas de mauvais branchements ni de court-circuits – une erreur peut endommager le matériel de la carte mère !
2. Test I2C
2.1. Installer les dépendances
PowerShell
sudo apt install -y python3-pip
sudo pip3 install smbus
sudo pip3 install Adafruit_SSD13062.2. Périphériques I2C
Lors du développement normal, il faut identifier le bus et l'adresse du périphérique I2C.
(1) Afficher les bus I2C
La commande suivante dans le terminal liste tous les bus du périphérique :
PowerShell
i2cdetect -l(2) Afficher les périphériques I2C
La commande suivante dans le terminal liste les périphériques I2C du bus spécifié : l'adresse I2C de l'OLED est 0x3c
PowerShell
i2cdetect -y -r *3. Vérifier l'adresse IP et le port
Utiliser ifconfig pour vérifier l'adresse IP et le port
Modifier le code en fonction du port réel
4. Résultat de l'expérience
Créer le fichier Oled_i2c.py
PowerShell
# (If gedit is not installed) sudo apt install gedit
sudo gedit Oled_i2c.pyCopier le code suivant, le coller dans le fichier, enregistrer et fermer
Python
#!/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.__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
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'")
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)
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! ")
passAprès le lancement du programme, l'OLED affiche des informations système telles que l'utilisation du CPU, l'heure système et l'utilisation de la mémoire :
Raspberry Pi, Orange Pi
1. Activer l'option I2C
Entrer dans les paramètres système du Raspberry Pi, choisir : Préférences → Raspberry Pi Configuration → Interfaces → trouver l'option I2C et l'activer ; le système redémarre ensuite. (voir figure ci-dessous)
En mode commande, sudo raspi-config permet également de trouver cette option, d'activer l'I2C puis de redémarrer le système.
2. Installer la bibliothèque I2C
PowerShell
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-venvIci, nous utilisons Python3. Après l'installation de la bibliothèque I2C, vérifier avec i2cdetect si le module d'affichage est reconnu
PowerShell
i2cdetect -y 1L'affichage indique que le périphérique a été détecté à l'adresse « 0x3c » (voir ci-dessous). L'adresse par défaut de ce type d'appareil est hexadécimale.
3. Configurer le fichier de police
Le code utilise la police DejaVuSansMono.ttf :
PowerShell
sudo apt-get install -y fonts-dejavu-coreOu modifier le code pour utiliser une police déjà présente sur le système (par ex. ImageFont.load_default())
4. Configurer les permissions
S'assurer que les permissions des fichiers de périphériques I2C sont correctes :
PowerShell
sudo chmod a+rw /dev/i2c-* # Temporary; for permanent effect, configure udev rules5. Vérifier l'adresse IP et le port
Utiliser ifconfig pour vérifier l'adresse IP et le port réels
PowerShell
# (If net-tools is not installed) sudo apt install net-tools
ifconfigModifier les deux zones encadrées dans le code en fonction du port réel
6. Créer le fichier Oled_i2c.py
Créer le fichier Oled_i2c.py dans le répertoire Home
PowerShell
# (If gedit is not installed) sudo apt install gedit
sudo gedit Oled_i2c.pyCopier le code suivant, le coller dans le fichier, enregistrer et fermer
Python
#!/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.__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
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'")
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)
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. Créer un environnement virtuel
PowerShell
# Install virtualenv tool (if not installed) sudo apt-get install -y python3-venv
# Create a virtual environment
python3 -m venv oled_env
# Activate:source oled_env/bin/activate # After activation, (oled_env) appears at the command prompt
# Install dependencies in the virtual environment
# Use the Aliyun mirror
pip install Adafruit_SSD1306 -i https://mirrors.aliyun.com/pypi/simple/
# Also install pillow (dependency)
pip install pillow -i https://mirrors.aliyun.com/pypi/simple/
# Run the code (must be inside the virtual environment)
# Go to the corresponding simple folder
cd /home/pi/oled-screen/luma.examples/examples
python3 oled_i2c.py # default bus 7
# Or specify a bus (e.g. bus 1)
python3 oled_i2c.py 1
# If a permission error occurs, check the sudo configuration or I2C device permissionsExemple du dépôt officiel
JUXI fournit un code de pilote open source pour les écrans OLED : GitHub
Exemple de pilote I2C
bash
sudo apt install -y python3-pip
sudo pip3 install smbus Adafruit_SSD1306python
import 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()