WDT（看门狗） 的使用

关于 WDT 详细介绍请参考WDT API 文档.

使用方法

看门狗主要用于保护系统正常运行，作用原理为，看门狗启动后，程序中必须定时执行一个喂狗的操作，当系统受到干扰不能正常运行时，喂狗操作也不能定时执行，此时看门狗将产生内部复位，使系统重新开始工作。

• 从 machine 导入 WDT 模块

from machine import WDT

• 定义回调函数，创建 WDT 对象

def on_wdt(self):
    print(self.context(), self)
    #self.feed()
    ## release WDT
    #self.stop()

# test callback wdt
wdt1 = WDT(id=1, timeout=4000, callback=on_wdt, context={})

• 喂狗

wdt1.feed()

可以在回调函数中执行喂狗操作

• 关闭看门狗

wdt1.stop()

示例

1. 喂一次狗后关闭
2. 不喂狗使得系统复位

import time
from machine import WDT

# '''
# test default wdt
wdt0 = WDT(id=0, timeout=3000)
print('into', wdt0)
time.sleep(2)
print(time.ticks_ms())
# 1.test wdt feed
wdt0.feed()
time.sleep(2)
print(time.ticks_ms())
# 2.test wdt stop
wdt0.stop()
print('stop', wdt0)
# 3.wait wdt work
#while True:
    #print('idle', time.ticks_ms())
    #time.sleep(1)
# '''

# '''
def on_wdt(self):
    print(self.context(), self)
    #self.feed()
    ## release WDT
    #self.stop()

# test callback wdt
wdt1 = WDT(id=1, timeout=4000, callback=on_wdt, context={})
print('into', wdt1)
time.sleep(2)
print(time.ticks_ms())
# 1.test wdt feed
wdt1.feed()
time.sleep(2)
print(time.ticks_ms())
# 2.test wdt stop
wdt1.stop()
print('stop', wdt1)
# 3.wait wdt work
#while True:
    #print('idle', time.ticks_ms())
    #time.sleep(1)
# '''

#'''
## test default and callback wdt
def on_wdt(self):
    print(self.context(), self)
    #self.feed()
    ## release WDT
    #self.stop()

wdt0 = WDT(id=0, timeout=3000, callback=on_wdt, context=[])
wdt1 = WDT(id=1, timeout=4000, callback=on_wdt, context={})
## 3.wait wdt work
while True:
    #wdt0.feed()
    print('idle', time.ticks_ms())
    time.sleep(1)
#'''

'''output
into [MAIXPY]WDT:(800cc560; id=0, timeout=3000, callback=800abcf8, context=800abcf8)
550247
552247
stop [MAIXPY]WDT:(800cc560; id=0, timeout=3000, callback=800abcf8, context=800abcf8)
into [MAIXPY]WDT:(800cc5e0; id=1, timeout=4000, callback=800cc5a0, context=800cc5c0)
554261
556261
stop [MAIXPY]WDT:(800cc5e0; id=1, timeout=4000, callback=800cc5a0, context=800cc5c0)
idle 556268
idle 557269
idle 558269
[] [MAIXPY]WDT:(800cc680; id=0, timeout=3000, callback=800cc620, context=800cc640)
idle 559275
{} [MAIXPY]WDT:(800cce40; id=1, timeout=4000, callback=800cc620, context=800cc6c0)
idle 560282
idle 561283

[MAIXPY] Pll0:freq:806000000
[MAIXPY] Pll1:freq:398666666
[MAIXPY] Pll2:freq:45066666
[MAIXPY] cpu:freq:403000000
[MAIXPY] kpu:freq:398666666
[MAIXPY] Flash:0xef:0x17
[MaixPy] gc heap=0x800c9850-0x80149850(524288)
[MaixPy] init end

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Official Site : https://www.sipeed.com
Wiki          : https://maixpy.sipeed.com

MicroPython v0.5.1-174-gf18990aa3-dirty on 2021-01-11; Sipeed_M1 with kendryte-k210
Type "help()" for more information.
'''