自從讀了陳會安老師的 "
超簡單 Python/MicroPython 物聯網應用" 這本書後我都改用書中提供的 xtools.py 函式庫, 但我有添加與改寫不分函式, 使得大小從 3KB 增加到 6KB, 上傳到 ESP8266 後發現會在呼叫函式時當機重啟, 已下是用 gc.mem_free() 追蹤記憶體耗用情形的紀錄 :
MicroPython v1.23.0 on 2024-06-02; ESP module with ESP8266
Type "help()" for more information.
>>> import gc
>>> gc.mem_free()
33568
開機後 160KB 的 SRAM 剩下 33.5KB (系統佔掉一大部分). 接
著匯入 6KB 的 xtools 與設定檔 :
>>> import config
>>> import xtools
>>> gc.mem_free()
24160
吃掉 9.4KB. 連線 WiFi :
>>> xtools.connect_wifi()
#4 ets_task(4020f540, 28, 3fffa050, 10)
Connecting to network...
network config: ('192.168.192.208', '255.255.255.0', '192.168.192.92', '192.168.192.92')
'192.168.192.208'
>>> gc.mem_free()
23920
低於 24KB 了. 呼叫 tw_now() 查詢 NTP 還可以 :
>>> xtools.tw_now()
Querying NTP server and set RTC time ... OK.
'2024-10-28 10:00:38'
>>> gc.mem_free()
23248
但呼叫 line_msg() 就會發生系統重啟動 (Reset) :
>>> xtools.line_msg(line_token, message)
ets Jan 8 2013,rst cause:2, boot mode:(3,6)
load 0x40100000, len 31212, room 16
tail 12
chksum 0xa6
ho 0 tail 12 room 4
load 0x3ffe8000, len 1060, room 12
tail 8
chksum 0x80
load 0x3ffe8430, len 1124, room 0
tail 4
chksum 0xcb
csum 0xcb
����n�r��n|�llll` b��|r�l�n��n�
研判是記憶體溢位造成, 可用的記憶體低於 24KB 會有此問題.
於是我將 xtools.py 中大部分我自行添加的函式刪除, 包含 set_ap(), line_sticker(), line_img_url(), 以及 ask_gpt(), 但留下 line_msg(), 盡量回歸到接近陳會安老師原著中的原始樣貌, 大小從 13KB 縮小到 5KB 左右 (書中原版約 3KB), 瘦身後的 ESP8266 版 xtools 如下 :
# xtools.py for ESP8266
from machine import Pin, RTC, unique_id
import urandom, math
import time, network, urequests
import ubinascii
import config
import ntptime
import ujson
def get_id():
return ubinascii.hexlify(unique_id()).decode('utf8')
def get_mac():
sta=network.WLAN(network.STA_IF)
mac=sta.config('mac')
return ubinascii.hexlify(mac, ':').decode('utf8')
def get_num(x):
return float("".join(ele for ele in x if ele.isdigit() or ele =="."))
def random_in_range(low=0, high=1000):
r1 = urandom.getrandbits(32)
r2 = r1 % (high-low) + low
return math.floor(r2)
def map_range(x, in_min, in_max, out_min, out_max):
return int((x-in_min) * (out_max-out_min) / (in_max-in_min) + out_min)
def connect_wifi(ssid=config.SSID, passwd=config.PASSWORD, led=2, timeout=20):
wifi_led=Pin(led, Pin.OUT, value=1)
sta=network.WLAN(network.STA_IF)
sta.active(True)
start_time=time.time() # 記錄時間判斷是否超時
if not sta.isconnected():
print("Connecting to network...")
sta.connect(ssid, passwd)
while not sta.isconnected():
wifi_led.value(0)
time.sleep_ms(300)
wifi_led.value(1)
time.sleep_ms(300)
# 判斷是否超過timeout秒數
if time.time()-start_time > timeout:
print("Wifi connecting timeout!")
break
if sta.isconnected():
for i in range(25): # 連線成功 : 快閃 5 秒
wifi_led.value(0)
time.sleep_ms(100)
wifi_led.value(1)
time.sleep_ms(100)
print("network config:", sta.ifconfig())
return sta.ifconfig()[0]
def scan_ssid():
sta=network.WLAN(network.STA_IF)
sta.active(True)
aps=sta.scan()
for ap in aps:
ssid=ap[0].decode()
mac=ubinascii.hexlify(ap[1], ':').decode()
rssi=str(ap[3]) + 'dBm'
print('{:>20} {:>20} {:>10}'.format(ssid, mac, rssi))
def show_error(final_state=0):
led = Pin(2, Pin.OUT) # Built-in D4
for i in range(3):
led.value(1)
time.sleep(0.5)
led.value(0)
time.sleep(0.5)
led.value(final_state)
def webhook_post(url, value):
print("invoking webhook")
r = urequests.post(url, data=value)
if r is not None and r.status_code == 200:
print("Webhook invoked")
else:
print("Webhook failed")
show_error()
return r
def webhook_get(url):
print("invoking webhook")
r = urequests.get(url)
if r is not None and r.status_code == 200:
print("Webhook invoked")
else:
print("Webhook failed")
show_error()
return r
def urlencode(params):
# 將字典的鍵值對轉換為 URL 編碼的字串 (k=v) 並以 & 連接多個鍵值對
kv=['{}={}'.format(k, v) for k, v in params.items()]
return '&'.join(kv)
def line_msg(token, message):
url="https://notify-api.line.me/api/notify"
headers={
"Authorization": "Bearer " + token,
"Content-Type": "application/x-www-form-urlencoded"
}
params={"message": message} # 參數字典
# 呼叫自訂的 URL 編碼函式將字典轉成 URL 字串, 再轉成 utf-8 編碼的 bytes
payload=urlencode(params).encode('utf-8')
# 用編碼後的 payload 傳給 data 參數發送 POST 請求
r=urequests.post(url, headers=headers, data=payload)
if r is not None and r.status_code == 200:
print("Message has been sent.")
else:
print("Error! Failed to send notification message.")
r.close() # 關閉連線
def tw_now():
try: # 從 NTP 取得 UTC 時戳加 8 為台灣時間, 若成功設定 RTC
print('Querying NTP server and set RTC time ... ', end='')
utc=ntptime.time() # 取得 UTC 時戳
print('OK.')
t=time.localtime(utc + 28800) # 傳回台灣時間的元組
rtc=RTC() # RTC 物件
rtc.datetime(t[0:3] + (0,) + t[3:6] + (0,)) # 設定 RTC
except: # 查詢 NTP 失敗不設定 RTC
print('Failed.')
return strftime() # 傳回目前之日期時間字串 YYYY-mm-dd HH:MM:SS
def strptime(dt_str, format_str="%Y-%m-%d %H:%M:%S"):
if format_str=="%Y-%m-%d %H:%M:%S":
year=int(dt_str[0:4])
month=int(dt_str[5:7])
day=int(dt_str[8:10])
hour=int(dt_str[11:13])
minute=int(dt_str[14:16])
second=int(dt_str[17:19])
return (year, month, day, hour, minute, second, 0, 0, 0)
else:
raise ValueError("Unsupported format string")
def strftime(dt=None, format_str="%Y-%m-%d %H:%M:%S"):
if dt is None:
dt=time.localtime()
return format_str.replace("%Y", str(dt[0])) \
.replace("%m", "{:02d}".format(dt[1])) \
.replace("%d", "{:02d}".format(dt[2])) \
.replace("%H", "{:02d}".format(dt[3])) \
.replace("%M", "{:02d}".format(dt[4])) \
.replace("%S", "{:02d}".format(dt[5]))
原始碼放在 GitHub :
將此 xtools.py 上傳 ESP8266 開發板重新測試追蹤記憶體耗用情形 :
MicroPython v1.23.0 on 2024-06-02; ESP module with ESP8266
Type "help()" for more information.
>>> import gc
>>> gc.mem_free()
35152
>>> import config
>>> import xtools
>>> gc.mem_free()
28640
瘦身下來多出 4KB 容量, 連線 WiFi :
>>> xtools.connect_wifi()
network config: ('192.168.192.208', '255.255.255.0', '192.168.192.92', '192.168.192.92')
'192.168.192.208'
>>> gc.mem_free()
28592
呼叫 tw_now() :
>>> xtools.tw_now()
Querying NTP server and set RTC time ... OK.
'2024-10-28 11:13:12'
>>> gc.mem_free()
29872
呼叫 line_msg() :
>>> line_token=config.LINE_NOTIFY_TOKEN
>>> message='test'
>>> gc.mem_free()
28400
>>> xtools.line_msg(line_token, message)
Message has been sent.
>>> gc.mem_free()
27424
可見減肥 3KB 是有效果的, 只要 SRAM 可用容量保持在 25KB 以上應該就沒問題.
2024-10-29 補充 :
雖然經過上面一番操作刪除一些函式將 xtools 瘦身後消除了記憶體溢位造成的當機問題, 但是函式庫寫法可能存在浪費記憶體的情形, 於是我將瘦身後的 xtools.py 貼給 ChatGPT 請它幫我檢查函式寫法是否有改進之處 :
"你是精通 MicroPython 的物聯網大師, 請問下列這個 xtools.py 函式庫是否有浪費記憶體的寫法? 有的話是哪個函式, 請分別指出改正寫法."
結果它指出下列優化建議 :
1. random_in_range() 可以用 urandom 來處理, 無須匯入 math, 改寫如下 :
def random_in_range(low=0, high=1000):
return urandom.getrandbits(32) % (high - low) + low
2. connect_wifi() 寫法改為如下 :
def connect_wifi(ssid=config.SSID, passwd=config.PASSWORD, led=2, timeout=20):
wifi_led=Pin(led, Pin.OUT, value=1)
sta=network.WLAN(network.STA_IF)
if not sta.active():
sta.active(True) # 確保已啟動 WiFi
start_time=time.time() # 記錄時間判斷是否超時
if not sta.isconnected():
print("Connecting to network...")
sta.connect(ssid, passwd)
while not sta.isconnected() and time.time() - start_time <= timeout:
wifi_led.value(0)
time.sleep_ms(300)
wifi_led.value(1)
time.sleep_ms(300)
if not sta.isconnected():
print("Wifi connecting timeout!")
return None
if sta.isconnected():
for _ in range(25): # 連線成功 : 快閃 5 秒
wifi_led.value(0)
time.sleep_ms(100)
wifi_led.value(1)
time.sleep_ms(100)
print("network config:", sta.ifconfig())
return sta.ifconfig()[0]
主要是迴圈改用 _ 當虛變數, 無法連線時傳回 None.
3. webhook_post() 與 webhook_get() 加入 finally 釋放資源 :
def webhook_post(url, value):
try:
r=urequests.post(url, data=value)
if r.status_code == 200:
print("Webhook invoked")
else:
print("Webhook failed")
show_error()
finally:
r.close() # 釋放資源
return r
def webhook_get(url):
try:
r=urequests.get(url)
if r.status_code == 200:
print("Webhook invoked")
else:
print("Webhook failed")
show_error()
finally:
r.close() # 釋放資源
return r
4. tw_now() 移除 rtc 變數直接用 RTC() :
def tw_now():
try: # 從 NTP 取得 UTC 時戳加 8 為台灣時間, 若成功設定 RTC
print('Querying NTP server and set RTC time ... ', end='')
utc=ntptime.time() # 取得 UTC 時戳
print('OK.')
t=time.localtime(utc + 28800) # 傳回台灣時間的元組
RTC().datetime(t[0:3] + (0,) + t[3:6] + (0,))
except Exception as e: # 加入例外處理
print(f'Failed. {e}')
return strftime() # 傳回目前之日期時間字串 YYYY-mm-dd HH:MM:SS
5. scan_ssid() 傳回值改用 f 字串嵌入 :
def scan_ssid():
sta=network.WLAN(network.STA_IF)
sta.active(True)
aps=sta.scan()
for ap in aps:
ssid=ap[0].decode()
mac=ubinascii.hexlify(ap[1], ':').decode()
rssi=str(ap[3]) + 'dBm'
print(f'{ssid} {mac} {rssi}')
優化後的完整 xtools for ESP8266 如下 :
# xtools.py for ESP8266 (optimized)
from machine import Pin, RTC, unique_id
import urandom, time, network, urequests, ubinascii, ntptime
import config
def get_id():
return ubinascii.hexlify(unique_id()).decode('utf8')
def get_mac():
sta=network.WLAN(network.STA_IF)
mac=sta.config('mac')
return ubinascii.hexlify(mac, ':').decode('utf8')
def get_num(x):
return float(''.join(filter(lambda c: c.isdigit() or c == ".", x)))
def random_in_range(low=0, high=1000):
return urandom.getrandbits(32) % (high - low) + low
def map_range(x, in_min, in_max, out_min, out_max):
return int((x-in_min) * (out_max-out_min) / (in_max-in_min) + out_min)
def connect_wifi(ssid=config.SSID, passwd=config.PASSWORD, led=2, timeout=20):
wifi_led=Pin(led, Pin.OUT, value=1)
sta=network.WLAN(network.STA_IF)
if not sta.active():
sta.active(True) # 確保已啟動 WiFi
start_time=time.time() # 記錄時間判斷是否超時
if not sta.isconnected():
print("Connecting to network...")
sta.connect(ssid, passwd)
while not sta.isconnected() and time.time() - start_time <= timeout:
wifi_led.value(0)
time.sleep_ms(300)
wifi_led.value(1)
time.sleep_ms(300)
if not sta.isconnected():
print("Wifi connecting timeout!")
return None
if sta.isconnected():
for _ in range(25): # 連線成功 : 快閃 5 秒
wifi_led.value(0)
time.sleep_ms(100)
wifi_led.value(1)
time.sleep_ms(100)
print("network config:", sta.ifconfig())
return sta.ifconfig()[0]
def scan_ssid():
sta=network.WLAN(network.STA_IF)
sta.active(True)
aps=sta.scan()
for ap in aps:
ssid=ap[0].decode()
mac=ubinascii.hexlify(ap[1], ':').decode()
rssi=str(ap[3]) + 'dBm'
print(f'{ssid} {mac} {rssi}')
def show_error(final_state=0):
led = Pin(2, Pin.OUT) # Built-in D4
for i in range(3):
led.value(1)
time.sleep(0.5)
led.value(0)
time.sleep(0.5)
led.value(final_state)
def webhook_post(url, value):
try:
r=urequests.post(url, data=value)
if r.status_code == 200:
print("Webhook invoked")
else:
print("Webhook failed")
show_error()
finally:
r.close() # 釋放資源
return r
def webhook_get(url):
try:
r=urequests.get(url)
if r.status_code == 200:
print("Webhook invoked")
else:
print("Webhook failed")
show_error()
finally:
r.close() # 釋放資源
return r
def urlencode(params):
# 將字典的鍵值對轉換為 URL 編碼的字串 (k=v) 並以 & 連接多個鍵值對
kv=['{}={}'.format(k, v) for k, v in params.items()]
return '&'.join(kv)
def line_msg(token, message):
url="https://notify-api.line.me/api/notify"
headers={
"Authorization": "Bearer " + token,
"Content-Type": "application/x-www-form-urlencoded"
}
params={"message": message} # 參數字典
# 呼叫自訂的 URL 編碼函式將字典轉成 URL 字串, 再轉成 utf-8 編碼的 bytes
payload=urlencode(params).encode('utf-8')
# 用編碼後的 payload 傳給 data 參數發送 POST 請求
r=urequests.post(url, headers=headers, data=payload)
if r is not None and r.status_code == 200:
print("Message has been sent.")
else:
print("Error! Failed to send notification message.")
r.close() # 關閉連線
def tw_now():
try: # 從 NTP 取得 UTC 時戳加 8 為台灣時間, 若成功設定 RTC
print('Querying NTP server and set RTC time ... ', end='')
utc=ntptime.time() # 取得 UTC 時戳
print('OK.')
t=time.localtime(utc + 28800) # 傳回台灣時間的元組
RTC().datetime(t[0:3] + (0,) + t[3:6] + (0,))
except Exception as e: # 加入例外處理
print(f'Failed. {e}')
return strftime() # 傳回目前之日期時間字串 YYYY-mm-dd HH:MM:SS
def strptime(dt_str, format_str="%Y-%m-%d %H:%M:%S"):
if format_str=="%Y-%m-%d %H:%M:%S":
year=int(dt_str[0:4])
month=int(dt_str[5:7])
day=int(dt_str[8:10])
hour=int(dt_str[11:13])
minute=int(dt_str[14:16])
second=int(dt_str[17:19])
return (year, month, day, hour, minute, second, 0, 0, 0)
else:
raise ValueError("Unsupported format string")
def strftime(dt=None, format_str="%Y-%m-%d %H:%M:%S"):
if dt is None:
dt=time.localtime()
return format_str.replace("%Y", str(dt[0])) \
.replace("%m", "{:02d}".format(dt[1])) \
.replace("%d", "{:02d}".format(dt[2])) \
.replace("%H", "{:02d}".format(dt[3])) \
.replace("%M", "{:02d}".format(dt[4])) \
.replace("%S", "{:02d}".format(dt[5]))
