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local mhz19 = {}
local c_read = string.char(0xff, 0x01, 0x86, 0x00, 0x00, 0x00, 0x00, 0x00, 0x79)
mhz19.co2 = nil
mhz19.temp = nil
mhz19.tt = nil
mhz19.ss = nil
mhz19.uu = nil
function mhz19.query()
return c_read
end
function mhz19.parse_frame(data)
local head, cmd, co2h, co2l, temp, tt, ss, uh, ul = struct.unpack("BBBBBBBBB", data)
if head ~= 0xff or cmd ~= 0x86 then
return false
end
mhz19.co2 = co2h * 256 + co2l
mhz19.temp = temp - 40
mhz19.tt = tt
mhz19.ss = ss
mhz19.uu = uh * 256 + ul
return true
end
return mhz19
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