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Support for versions of NodeMCU with float point 

Read error is indicated with humidity = nil
This commit is contained in:
Javier Yáñez 2015-02-02 09:59:20 +01:00
parent 055c55a73c
commit a3e518724c
1 changed files with 5 additions and 3 deletions
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8
lua_modules/dht22/dht22.lua
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@ -77,15 +77,17 @@ function M.read(pin)
end end
end end
checksumTest=((humidity / 256) + (humidity % 256) + (temperature / 256) + (temperature % 256)) % 256 checksumTest = (bit.band(humidity, 0xFF) + bit.rshift(humidity, 8) + bit.band(temperature, 0xFF) + bit.rshift(temperature, 8))
checksumTest = bit.band(checksumTest, 0xFF)
if temperature > 0x8000 then if temperature > 0x8000 then
-- convert to negative format -- convert to negative format
temperature = -(temperature - 0x8000) temperature = -(temperature - 0x8000)
end end
if checksum ~= checksumTest then -- conditions compatible con float point and integer
humidity = -1 if (checksumTest - checksum >= 1) or (checksum - checksumTest >= 1) then
humidity = nil
end end
end end