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local pm1006 = {}
function pm1006.parse_frame(data)
if string.byte(data, 1) ~= 0x16 or string.byte(data, 2) ~= 0x11 or string.byte(data, 3) ~= 0x0b then
-- invalid header
return nil
end
local checksum = 0
for i = 1, 20 do
checksum = (checksum + string.byte(data, i)) % 256
end
if checksum ~= 0 then
-- invalid checksum
return nil
end
local pm2_5 = string.byte(data, 6) * 256 + string.byte(data, 7)
return pm2_5
end
return pm1006
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