Mitsubishi air conditioning resolved infrared code value encoding rules
First, the principle of infrared control air conditioning
Air conditioning remote control is used to transmit information by emitting infrared light off, we can put the time of transmission seen as "1", when not launch seen as "0", so the signal can be transmitted out of turn act as a group of data communication, different keys transmitted at a different encoding. When the air conditioner receives the infrared light in accordance with the rules laid decoder can know what commands sent by the remote control to perform the corresponding operations.
The same brand of air conditioning, their coding rules are the same, so we just find their infrared emission of encoding rules, you can simulate this signal to control the air conditioning all the brand.
Second, the decoding principle
To crack the coding rules, the first to use infrared receiving tube to receive infrared signals sent to the air conditioning, then use an oscilloscope to observe the signal. Air conditioning front IR codes generally have at least a boot code, a specific time is low and the high level of composition, do not know the students can go to check the NEC rules. Then data is then transmitted to the general data "0" and "1" is a composition of high a low + a, but the level is not the same time, different brands of air conditioning, "0" and " 1 "high and low time there are differences. Well, then know this information, you can use the microcontroller to capture these levels, and by collecting the duration of each level you can know the transmission data is "0" or "1", and then through the serial port printed on it to obtain a complete frame of data. Then measure multiple sets of data by changing certain variables, find out the law can change that part of the launch of the encoding rules.
Third, the level rules
A full data: to 165 ms
boot code: low for approximately 3.2ms, about 1.6ms high
data "0": Low 350 ~ 400us, 450 ~ 500us high level
data "1": low level 350 ~ 400us, the high level of about 1300us
Note: the duration of these there is a certain level of fault tolerance space, so not necessarily in strict accordance with this value to transmit infrared signals, if you find that these values can not be controlled by air conditioning, this can the basis of the value of the upper edge of amendments to try, can always find a suitable value.
Fourth, the encoding rules
Switch: On: Off 1: 0
Mode: Cooling: 100 dehumidification: 101 cycle: 110 Ventilation: 000 Heating: 010
Temperature :( temperature -16) (reverse)
wind speed: Level 1: 000 2: 100 Level 3: 010 level 4: 110
swept modes: vertical sweep air (0 to 90 degrees): 001 swept laterally (0 degrees): 110 down 30 degrees: 60 degrees down 010: 100 down 90: 000
, such as: 24 degrees = (24--16) (reverse) = 1000 (reverse) = 0001
Note: regular boot, shutdown and sleep timer not need to use these in my project, so did not go to the law, the timer switch in my experience should be separately represented by 8 bits, is likely to be in the swing mode behind, interested students can go and find me follow this method. Mitsubishi is positive and negative codes, no parity, relatively simple and should be easy to find.
Well, the code value on air conditioning Mitsubishi will stop here, if you have any questions, you can leave a message to me, if the article is wrong, be sure to point it out, if this post is just to help you can give me a praise ,Thank you! ! !
