Placa de dezvoltare WiFi cu ESP8266

Placa de dezvoltate WiFi bazată pe ESP8266, un circuit integrat care contine module GPIO, PWM, IIC, 1-Wire și ADC, toate pe o singură placă și facil de utilizat cu sintaxa gen Arduino pentru acces la hardware și API în stilul NodeJS pentru utilizarea rețelei.

Exemplu de conectare la retea:

print(wifi.sta.getip())
--nil
wifi.setmode(wifi.STATION)
wifi.sta.config("SSID","password")
print(wifi.sta.getip())
--192.168.18.110

Exemplu de I/O:

pin = 1
gpio.mode(pin,gpio.OUTPUT)
gpio.write(pin,gpio.HIGH)
gpio.mode(pin,gpio.INPUT)
print(gpio.read(pin))

Exemplu de client HTTP:

-- A simple http client
conn=net.createConnection(net.TCP, false) 
conn:on("receive", function(conn, pl) print(pl) end)
conn:connect(80,"121.41.33.127")
conn:send("GET / HTTP/1.1rnHost: www.nodemcu.comrn"
    .."Connection: keep-alivernAccept: */*rnrn")

Exemplu de server HTTP:

-- a simple http server
srv=net.createServer(net.TCP) 
srv:listen(80,function(conn) 
    conn:on("receive",function(conn,payload) 
    print(payload) 
    conn:send("</code></pre>
<h1>Hello, NodeMCU.</h1>
<pre><code>")
    end) 
end)

Exemplu de PWM:

function led(r,g,b) 
    pwm.setduty(1,r) 
    pwm.setduty(2,g) 
    pwm.setduty(3,b) 
end
pwm.setup(1,500,512) 
pwm.setup(2,500,512) 
pwm.setup(3,500,512)
pwm.start(1) 
pwm.start(2) 
pwm.start(3)
led(512,0,0) -- red
led(0,0,512) -- blue

Exemplu de PWM:

function led(r,g,b) 
    pwm.setduty(1,r) 
    pwm.setduty(2,g) 
    pwm.setduty(3,b) 
end
pwm.setup(1,500,512) 
pwm.setup(2,500,512) 
pwm.setup(3,500,512)
pwm.start(1) 
pwm.start(2) 
pwm.start(3)
led(512,0,0) -- red
led(0,0,512) -- blue

Exemplu de cod pentru LED care se aprinde intermitent (blinking):

lighton=0
tmr.alarm(0,1000,1,function()
if lighton==0 then 
    lighton=1 
    led(512,512,512) 
    -- 512/1024, 50% duty cycle
else 
    lighton=0 
    led(0,0,0) 
end 
end)

Exemplu de interfatare cu senzori:

-- read temperature with DS18B20
t=require("ds18b20")
t.setup(9)
addrs=t.addrs()
-- Total DS18B20 numbers, assume it is 2
print(table.getn(addrs))
-- The first DS18B20
print(t.read(addrs[1],t.C))
print(t.read(addrs[1],t.F))
print(t.read(addrs[1],t.K))
-- The second DS18B20
print(t.read(addrs[2],t.C))
print(t.read(addrs[2],t.F))
print(t.read(addrs[2],t.K))
-- Just read
print(t.read())
-- Just read as centigrade
print(t.read(nil,t.C))
-- Don't forget to release it after use
t = nil
ds18b20 = nil
package.loaded["ds18b20"]=nil

Resurse externe

• NodeMCU Wiki
• NodeMCU DevKit
• NodeMCU Firmware
• Mediu de dezvoltare pentru ESP8266