I've got an ESP8266 201 (http://smarpl.com/sites/default/files/i ... ce-v01.png)
i am trying to connect a DS18B20 to it and send the inforamation to thingsspeak.com (any other IOT platform information is gladly received if you think there are better ones.)
The code below was uploaded using LUA Loader, but i would really prefer to use the arduino IDE if possible, I guess it would mean writing an Arduino Sketch.
My problems are:-
1. No data is geting to thingsspeak.com
2. I dont know how to see if any data is being collected by the DS18B20
The DS18B20 is connected as follows
Pin 1 GND
Pin 2 ESP Pin 9 (IO14)
Pin 3 VCC 3.3V
The following is the code i uploaded to the ESP
-- Measure temperature and post data to thingspeak.com
-- 2014 OK1CDJ
--- Tem sensor DS18B20 is conntected to GPIO0
--- 2015.01.21 sza2 temperature value concatenation bug correction
pin = 9
ow.setup(pin)
counter=0
lasttemp=-999
function bxor(a,b)
local r = 0
for i = 0, 31 do
if ( a % 2 + b % 2 == 1 ) then
r = r + 2^i
end
a = a / 2
b = b / 2
end
return r
end
--- Get temperature from DS18B20
function getTemp()
addr = ow.reset_search(pin)
repeat
tmr.wdclr()
if (addr ~= nil) then
crc = ow.crc8(string.sub(addr,1,7))
if (crc == addr:byte(8)) then
if ((addr:byte(1) == 0x10) or (addr:byte(1) == 0x28)) then
ow.reset(pin)
ow.select(pin, addr)
ow.write(pin, 0x44, 1)
tmr.delay(1000000)
present = ow.reset(pin)
ow.select(pin, addr)
ow.write(pin,0xBE, 1)
data = nil
data = string.char(ow.read(pin))
for i = 1, 8 do
data = data .. string.char(ow.read(pin))
end
crc = ow.crc8(string.sub(data,1,8))
if (crc == data:byte(9)) then
t = (data:byte(1) + data:byte(2) * 256)
if (t > 32768) then
t = (bxor(t, 0xffff)) + 1
t = (-1) * t
end
t = t * 625
lasttemp = t
print("Last temp: " .. lasttemp)
end
tmr.wdclr()
end
end
end
addr = ow.search(pin)
until(addr == nil)
end
--- Get temp and send data to thingspeak.com
function sendData()
getTemp()
t1 = lasttemp / 10000
t2 = (lasttemp >= 0 and lasttemp % 10000) or (10000 - lasttemp % 10000)
print("Temp:"..t1 .. "."..string.format("%04d", t2).." C\n")
-- conection to thingspeak.com
print("Sending data to thingspeak.com")
conn=net.createConnection(net.TCP, 0)
conn:on("receive", function(conn, payload) print(payload) end)
-- api.thingspeak.com 184.106.153.149
conn:connect(80,'184.106.153.149')
conn:send("GET /update?key=*****MYKEYGOESHERE*****&field1="..t1.."."..string.format("%04d", t2).." HTTP/1.1\r\n")
conn:send("Host: api.thingspeak.com\r\n")
conn:send("Accept: */*\r\n")
conn:send("User-Agent: Mozilla/4.0 (compatible; esp8266 Lua; Windows NT 5.1)\r\n")
conn:send("\r\n")
conn:on("sent",function(conn)
print("Closing connection")
conn:close()
end)
conn:on("disconnection", function(conn)
print("Got disconnection...")
end)
end
-- send data every X ms to thing speak
tmr.alarm(0, 60000, 1, function() sendData() end )