Does not look like any protocol I have ever seen.
Unless somebody else can spot a known protocol, then I guess you will have to write your own code to handle it.
Note that IR 3-pin receiver modules usually distort the transmitted signal (and by different amounts depending on range). If memory serves, marks are elongated and spaces shortened a little. For example, your 0.45 high - 1.6 low may actually be transmitted as perhaps 0.5 high and 1.5 low - ie regular timing units (t= approx 0.5 mS) of 1t high, 3t low.
I think that is me out of ideas for now.... good luck
EDIT: Oh.... or else just use a universal remote with learning capability. Not that any remote is truly universal. What we don't know yet is the modulation frequency used by your Air Conditioner remote control. 36, 38 or 40kHz are all easily handled by most learning remotes. 56 kHz is handled by many remotes, but not all. Other frequencies might only be handled by the most expensive remote controls.
What I have noticed is that "learned" messages are often not transmitted as reliably as the original remote transmitted signal. I tend to write my own code to more accurately transmit an accurate message, but then I am lucky that I have a lot of resources, understanding and interest.
What I have never achieved is making a remote as nice as commercial remote controls. Battery life on home made remote is severely limited. Best result I ever achieved was by building a receiver/transmitter that recognised spare buttons on my TV remote and then re-transmitted a different bespoke message to a foreign device (in my case a TV with lost remote). Even this was not ideal, as there has to be a delay between receiving and re-transmitting. Repeat codes were not catered for (such as holding down vol+ to give smooth volume increase.
Hello again,
No problem with the IR 3 pin receive module, i am using a pin photo diode...real fast and picks up the carrier too, which BTW looks like 40kHz for this unit. The delay with this kind of diode is on the order of 5 nanoseconds.
I was going to try the universal remote, which does do 56kHz BTW, but i did not have a manufacturers code for the AC unit. The data sheet only shows TV's and other enetertainment devices like DVR's etc.
There is a way to 'hunt' for the code using the remote, but i did not get around to trying that yet.
As far as battery life, if you havent noticed yet, the game is all about efficiency and device duty cycle.
The efficiency is hard to adjust with a remote because of the battery voltage vs LED voltage, but the duty cycle
can be adjusted quite extensively by using the watchdog timer. The watchdog timer is set, then the microcontroller
is put to sleep. When the time expires the uC wakes up and in the interrupt routine you do a scan of the keys,
noting if ANY key is pressed, and if so, scan again to read the key, but if no key then set the timer again and
put back to sleep again. You can get the 'awake' duty cycle down very very low, such that the battery life
is extended into the years when the remote is not being used. Of course this requires a uC chip such as a PIC
that uses micropower or nanopower when put to sleep. My fridge monitor gets 2 years on two AA size alkaline
batteries. When a remote is transmitting, it must use power, no way around that, but with the timer sleep
schedual the remote will look like a commercial unit which only needs battery replacement now and then.
Here are some lousy scope pictures, but they show the actual measurements. The camera was hard to hold still.
You can see the pin photo diode picks up the carrier too, but with this time scale shows up as a blur.
The two traces show pulses picked up for two different buttons pushed.