Anyone used Pronto hex codes (remote control)

[Professor601]

Greetings, all.

Back to dabbling a little on the breadboard. I am considering a small "universal remote" project that could send the power on-off code for various common brands. I can find lots of Pronto codes online that give the hex timing for IR pulses (at least, I think that is what they do). But I am not quite certain how to rig that into a Picaxe, and thought I would ask if anyone else here has tried it so I didn't reinvent the wheel. I think it should be a simple matter of looping through high / low timing pulses, but again if there is experience and knowledge already out there, I am glad to use it.

Courteously,
The Professor (601)

 

[hippy]

It should be possible to bit-bang out IR remote codes providing the pulses are not too short. The PICAXE has a limit on the shortest pulse limits though I am not sure what that is off hand and perhaps depends on the means used to do it; whether sequentially coded as HIGH/LOW/PAUSEUS, or forming the sequence in variable RAM and just churning that out.

If one can use some form of large enough external memory and clock data out at an appropriate rate, it should be possible to generate any IR code required.

As for using Pronto codes; that would probably require needing to know what those codes actually mean.

 

[mikeyBoo]

hi Prof,
I have been using X10 <--> IR <--> etc. for home control for a couple of decades. Since the little box I designed way back when
is still working, guess the hardware design is sound. Only interact with it when I need to learn IR codes for a new TV (etc.).
Looking at the old schematic, don't know why I used a PNP instead of an NPN (maybe was what I had on hand). If I did it today,
would use an NPN & reverse LM339 pins 6 & 7.
The box has an 8052-Basic chip in it, but looks like I wrote the IR/X10 code in assembly language, so I don't think it
would help much to upload it.
Looking at the notes from my old code, it would seem that the IR would need to be sampled/played back at >13KHz, so it may
not be feasible to use a Picaxe for sampling to memory. I believe Hippy is right, if you could generate a sample clock from the Picaxe
& store samples into a bit-wide external memory, you could probably pull it off (surely someone has built an external sampler).
Anyhow, I attached the old schematic I found for the IR/X10 hardware (may be a starting point for you).
Here is the comment leader from the ir_learn procedure. Maybe that will help. Good luck!
Note: If you solve this for Picaxe, please share.

notes from old 805x assembly:
;-----------------------------------------------------------------------------\
; Function : Learn a code from an IR (infra-red) remote |
; Enter With : |
; Exits With : |
; |
; Remarks : Touch any key to abort. |
; CAUTION !! This routine depends on the system clock for its |
; accuracy. Calculations were derived based on an 11.0592 Mhz |
; crystal. Be aware that IRQs will degrade the accuracy of the|
; transmitted data. clock cycle =1.085uS |
; 24 cycles in loop below + 46 cycles for learn_ir5 call |
; so that 1/(70 x 1.085uS) = Sampling rate = 13166 Samples/Second|
; The sampling rate may be slowed by changing the value of r0 in |
; the first line of txmt_ir/learn_ir. The sampling rates will |
; track up and down for both as long as you ALWAYS have 3 more |
; bits in learn_ir's r0 than in txmt_ir's r0. Take note that |
; since most IR signals have bit times of ~.0005 sec., decreasing|
; sample times below 10,000 samples/sec will yield errors of |
; > 20 %. Unless there is a noisy IR signal being measured, |
; higher sample rates use no more memory to store an IR code than|
; slower rates since learn_ir is looking for changes in input |
; state and not linear sampling. |
; sample interval in real time = (70 x 1.085uS) = .00007595 sec. |
; r3/r4 = # of sample intervals |
; r5/r6 = current sampling interval count |
; r7 = holds previous value of IR input pin |
; |
; Dependency : sub_16_bit |
; Declarator : (for use with the user function table) |
; ljmp learn_ir ; xxx learn a command from an IR remote |
;-----------------------------------------------------------------------------|