【Micropython ESP32】 SSD1306 0.96 "OLED+Network Clock

• This example is based onThonnyPlatform development.
• Display effect
  

Display part

• usessd 1306 0.96 "OLED screen to display time.
• Wiring description:

0.96"OLED ----ESP32
SCL  ---- 22
SDA ---- 21

• Before running the debugging code, you need tossd1306.pySave it on the Micropython device and run the main code.
  

SSD1306 module download link ::

• Chinese download station:https://www.cnpython.com/pypi/micropython-ssd1306/download
• Official download station:https://pypi.org/project/micropython-ssd1306/
• ssd1306.pyThe code is as follows; (copy it and save it asssd1306.pyOn the Micropython device)

# MicroPython SSD1306 OLED driver, I2C and SPI interfaces

from micropython import const
import framebuf


# register definitions
SET_CONTRAST = const(0x81)
SET_ENTIRE_ON = const(0xA4)
SET_NORM_INV = const(0xA6)
SET_DISP = const(0xAE)
SET_MEM_ADDR = const(0x20)
SET_COL_ADDR = const(0x21)
SET_PAGE_ADDR = const(0x22)
SET_DISP_START_LINE = const(0x40)
SET_SEG_REMAP = const(0xA0)
SET_MUX_RATIO = const(0xA8)
SET_COM_OUT_DIR = const(0xC0)
SET_DISP_OFFSET = const(0xD3)
SET_COM_PIN_CFG = const(0xDA)
SET_DISP_CLK_DIV = const(0xD5)
SET_PRECHARGE = const(0xD9)
SET_VCOM_DESEL = const(0xDB)
SET_CHARGE_PUMP = const(0x8D)

# Subclassing FrameBuffer provides support for graphics primitives
# http://docs.micropython.org/en/latest/pyboard/library/framebuf.html
class SSD1306(framebuf.FrameBuffer):
    def __init__(self, width, height, external_vcc):
        self.width = width
        self.height = height
        self.external_vcc = external_vcc
        self.pages = self.height // 8
        self.buffer = bytearray(self.pages * self.width)
        super().__init__(self.buffer, self.width, self.height, framebuf.MONO_VLSB, self.width)
        self.init_display()

    def init_display(self):
        for cmd in (
            SET_DISP | 0x00,  # off
            # address setting
            SET_MEM_ADDR,
            0x00,  # horizontal
            # resolution and layout
            SET_DISP_START_LINE | 0x00,
            SET_SEG_REMAP | 0x01,  # column addr 127 mapped to SEG0
            SET_MUX_RATIO,
            self.height - 1,
            SET_COM_OUT_DIR | 0x08,  # scan from COM[N] to COM0
            SET_DISP_OFFSET,
            0x00,
            SET_COM_PIN_CFG,
            0x02 if self.width > 2 * self.height else 0x12,
            # timing and driving scheme
            SET_DISP_CLK_DIV,
            0x80,
            SET_PRECHARGE,
            0x22 if self.external_vcc else 0xF1,
            SET_VCOM_DESEL,
            0x30,  # 0.83*Vcc
            # display
            SET_CONTRAST,
            0xFF,  # maximum
            SET_ENTIRE_ON,  # output follows RAM contents
            SET_NORM_INV,  # not inverted
            # charge pump
            SET_CHARGE_PUMP,
            0x10 if self.external_vcc else 0x14,
            SET_DISP | 0x01,
        ):  # on
            self.write_cmd(cmd)
        self.fill(0)
        self.show()

    def poweroff(self):
        self.write_cmd(SET_DISP | 0x00)

    def poweron(self):
        self.write_cmd(SET_DISP | 0x01)

    def contrast(self, contrast):
        self.write_cmd(SET_CONTRAST)
        self.write_cmd(contrast)

    def invert(self, invert):
        self.write_cmd(SET_NORM_INV | (invert & 1))

    def show(self):
        x0 = 0
        x1 = self.width - 1
        if self.width == 64:
            # displays with width of 64 pixels are shifted by 32
            x0 += 32
            x1 += 32
        self.write_cmd(SET_COL_ADDR)
        self.write_cmd(x0)
        self.write_cmd(x1)
        self.write_cmd(SET_PAGE_ADDR)
        self.write_cmd(0)
        self.write_cmd(self.pages - 1)
        self.write_data(self.buffer)


class SSD1306_I2C(SSD1306):
    def __init__(self, width, height, i2c, addr=0x3C, external_vcc=False):
        self.i2c = i2c
        self.addr = addr
        self.temp = bytearray(2)
        self.write_list = [b"\x40", None]  # Co=0, D/C#=1
        super().__init__(width, height, external_vcc)

    def write_cmd(self, cmd):
        self.temp[0] = 0x80  # Co=1, D/C#=0
        self.temp[1] = cmd
        self.i2c.writeto(self.addr, self.temp)

    def write_data(self, buf):
        self.write_list[1] = buf
        self.i2c.writevto(self.addr, self.write_list)


class SSD1306_SPI(SSD1306):
    def __init__(self, width, height, spi, dc, res, cs, external_vcc=False):
        self.rate = 10 * 1024 * 1024
        dc.init(dc.OUT, value=0)
        res.init(res.OUT, value=0)
        cs.init(cs.OUT, value=1)
        self.spi = spi
        self.dc = dc
        self.res = res
        self.cs = cs
        import time

        self.res(1)
        time.sleep_ms(1)
        self.res(0)
        time.sleep_ms(10)
        self.res(1)
        super().__init__(width, height, external_vcc)

    def write_cmd(self, cmd):
        self.spi.init(baudrate=self.rate, polarity=0, phase=0)
        self.cs(1)
        self.dc(0)
        self.cs(0)
        self.spi.write(bytearray([cmd]))
        self.cs(1)

    def write_data(self, buf):
        self.spi.init(baudrate=self.rate, polarity=0, phase=0)
        self.cs(1)
        self.dc(1)
        self.cs(0)
        self.spi.write(buf)
        self.cs(1)

Instance code

# ESP32 MicroPython Web Clock

import network
import urequests
import ujson
import utime
From SSD1306 Import SSD1306_i2c #Import SSD1306_i2C submissis from the SSD1306 module
from machine import RTC, I2C, Pin
 
# user data
ssid = "MERCURY_D268G" # wifi router name
pw = "pba5ayzk" # wifi router password

url = 'http://worldtimeapi.org/api/timezone/Asia/Hong_Kong'

web_query_delay = 60000 # interval time of web JSON query
retry_delay = 5000 # interval time of retry after a failed Web query

# SSD1306 OLED display
print("Connecting to wifi...")
i2c = I2C(1,sda=Pin(21), scl=Pin(22),freq=100000)
oled = SSD1306_I2C(128, 64, i2c,addr=0x3c)
oled.fill(0)
oled.text("Connecting", 0, 0)
oled.text(" to wifi...", 15, 16)
oled.show()
 
# internal real time clock
rtc = RTC()
 
# wifi connection
wifi = network.WLAN(network.STA_IF) # station mode
while(not wifi.isconnected()):
    wifi.active(True)
    try:
        wifi.connect(ssid,pw)  # wifi network information       
        utime.sleep(1.0)
    except OSError:
        print("OSError")
        utime.sleep(2.0)

 
# wifi connected
print("IP: " + str(wifi.ifconfig()[0]) + "\n")
oled.text("Connected. IP: ", 0, 30)
oled.text(" " + str(wifi.ifconfig()[0]), 0, 45)
oled.show()
 
# set timer
update_time = utime.ticks_ms() - web_query_delay
# main loop
while True:
        
    # if lose wifi connection reboot ESP32
    if not wifi.isconnected():
        
        machine.reset()
    
    # query and get web JSON every web_query_delay ms
    if utime.ticks_ms() - update_time >= web_query_delay:        # HTTP GET data
        
        response = urequests.get(url)
    
        if response.status_code == 200: # query success
                    
            print("JSON response:\n" + response.text)
            
            # parse JSON
            parsed = ujson.loads(response.text) 
			# you can also use parsed = response.json()
            datetime_str = str(parsed["datetime"])
            year = int(datetime_str[0:4])
            month = int(datetime_str[5:7])
            day = int(datetime_str[8:10])
            hour = int(datetime_str[11:13])
            minute = int(datetime_str[14:16])
            second = int(datetime_str[17:19])
            subsecond = int(round(int(datetime_str[20:26]) / 10000))
        
            # update internal RTC
            rtc.datetime((year, month, day, 0, hour, minute, second, subsecond))
            update_time = utime.ticks_ms()
            print("RTC updated\n")
   
        else: # query failed, retry retry_delay ms later
            update_time = utime.ticks_ms() - web_query_delay + retry_delay
    
    # generate formated date/time strings from internal RTC
    date_str = "{:02}/{:02}/{:4}".format(rtc.datetime()[1], rtc.datetime()[2], rtc.datetime()[0])
    time_str = "{:02}:{:02}:{:02}".format(rtc.datetime()[4], rtc.datetime()[5], rtc.datetime()[6])
 
    # update SSD1306 OLED display
    oled.fill(0)
    oled.text("ESP32 Clock", 20, 0)
    oled.line(0, 14, 128, 14, 1)#
    oled.text("Date: " + date_str, 0, 25)
    oled.text("Time: " + time_str, 0, 45)
    oled.show()
    
    utime.sleep(0.1)
    

Replace the API interface

• Suning API interface:http://quan.suning.com/getSysTime.do

Save the accuracy of milliseconds, but the acquisition is relatively simple.

# ESP32 MicroPython Web Clock
import urequests
import network
#import urequests
import ujson
import utime
 From SSD1306 Import SSD1306_i2c #Import SSD1306_i2C submissis from the SSD1306 module
from machine import RTC, I2C, Pin
 
# user data
ssid = "MERCURY_D268G" # wifi router name
pw = "pba5ayzk" # wifi router password

#url = 'http://worldtimeapi.org/api/timezone/Asia/Hong_Kong'
url ='http://quan.suning.com/getSysTime.do'
'''
{"sysTime2":"2022-08-21 13:31:51","sysTime1":"20220821133151"}
'''
web_query_delay = 60000 # interval time of web JSON query
retry_delay = 5000 # interval time of retry after a failed Web query

# SSD1306 OLED display
print("Connecting to wifi...")
i2c = I2C(1,sda=Pin(21), scl=Pin(22),freq=100000)
oled = SSD1306_I2C(128, 64, i2c,addr=0x3c)
oled.fill(0)
oled.text("Connecting", 0, 0)
oled.text(" to wifi...", 15, 16)
oled.show()
 
# internal real time clock
rtc = RTC()
 
# wifi connection
wifi = network.WLAN(network.STA_IF) # station mode
while(not wifi.isconnected()):
    wifi.active(True)
    try:
        wifi.connect(ssid,pw)  # wifi network information       
        utime.sleep(1.0)
    except OSError:
        print("OSError")
        utime.sleep(2.0)

 
# wifi connected
print("IP: " + str(wifi.ifconfig()[0]) + "\n")
oled.text("Connected. IP: ", 0, 30)
oled.text(" " + str(wifi.ifconfig()[0]), 0, 45)
oled.show()
 
# set timer
update_time = utime.ticks_ms() - web_query_delay
# main loop
while True:
        
    # if lose wifi connection reboot ESP32
    if not wifi.isconnected():
        
        machine.reset()
    
    # query and get web JSON every web_query_delay ms
    if utime.ticks_ms() - update_time >= web_query_delay:        # HTTP GET data 1Update every minute
        
        response = urequests.get(url)
    
        if response.status_code == 200: # query success
                    
            print("JSON response:\n" + response.text)
            
            # parse JSON
            parsed = ujson.loads(response.text) 
			# you can also use parsed = response.json()
            datetime_str = str(parsed["sysTime2"])
            year = int(datetime_str[0:4])
            month = int(datetime_str[5:7])
            day = int(datetime_str[8:10])
            hour = int(datetime_str[11:13])
            minute = int(datetime_str[14:16])
            second = int(datetime_str[17:19])
#             subsecond = int(round(int(datetime_str[20:26]) / 10000))# Milliseconds
        
            # update internal RTC
            rtc.datetime((year, month, day, 0, hour, minute, second, 0))
            update_time = utime.ticks_ms()
            print("RTC updated\n")
   
        else: # query failed, retry retry_delay ms later
            update_time = utime.ticks_ms() - web_query_delay + retry_delay
    
    # generate formated date/time strings from internal RTC
    date_str = "{:02}/{:02}/{:4}".format(rtc.datetime()[1], rtc.datetime()[2], rtc.datetime()[0])
    time_str = "{:02}:{:02}:{:02}".format(rtc.datetime()[4], rtc.datetime()[5], rtc.datetime()[6])
 
    # update SSD1306 OLED display
    oled.fill(0)
    oled.text("ESP32 Clock", 20, 0)
    oled.line(0, 14, 128, 14, 1)#
    oled.text("Date: " + date_str, 0, 25)
    oled.text("Time: " + time_str, 0, 45)
    oled.show()
    
    utime.sleep(0.1)
    

• SHELL debug window output information