NodeMCU Projects: Difference between revisions

= Small Projects =

== Playing with GPIO ==

<syntaxhighlight lang="python">

import machine

import time

import urandom

pin = machine.Pin(2, machine.Pin.OUT)

def toggle(p):

p.value(not p.value())

while True:

time.sleep_ms(urandom.getrandbits(8))

toggle(pin)

</syntaxhighlight>

== Fading an LED ==

<syntaxhighlight lang="python">

import time, math

import machine

led = machine.PWM(machine.Pin(2), freq=1000)

def pulse(l, t):

for i in range(20):

l.duty(int(math.sin(i / 10 * math.pi) * 500 + 500))

time.sleep_ms(t)

while True:

pulse(led, 20)

</syntaxhighlight>

== Control a hobby servo ==

#Hobby servo motors can be controlled using PWM.

#They require a frequency of 50Hz and a duty between about 40 and 115, with 77 being the center value.

*Manual Movements

<syntaxhighlight lang="python">

servo = machine.PWM(machine.Pin(12), freq=50)

servo.duty(40)

servo.duty(115)

servo.duty(77)

</syntaxhighlight>

*Random movements:

<syntaxhighlight lang="python">

servo = machine.PWM(machine.Pin(12), freq=50)

while True:

servo.duty(urandom.getrandbits(8))

time.sleep(1)

</syntaxhighlight>

== One Wire DS18B20 Temp Sensor ==

<syntaxhighlight lang="python">

import time

import machine

import onewire, ds18x20

# the device is on GPIO12

dat = machine.Pin(12)

# create the onewire object

ds = ds18x20.DS18X20(onewire.OneWire(dat))

# scan for devices on the bus

roms = ds.scan()

print('found devices:', roms)

# loop 10 times and print all temperatures

for i in range(10):

print('temperatures:', end=' ')

ds.convert_temp()

time.sleep_ms(750)

for rom in roms:

print(ds.read_temp(rom), end=' ')

print()

</syntaxhighlight>