Re: Weirdness when trying to send commands to a Samsung TV

On 2019-11-06 21:34, Sahbi via LIRC-list wrote:
> Alright, since you seem to prefer IrScrutinizer I've installed it on Pi 
> B and simply connected to the DE using VNC. I'm assuming with "3 
> repeats" you mean using -# 3, although it's probably not any different 
> to just SEND_ONCE thrice in a row. 

No, it is not! I was suspecting that the timings between the different 
repeats (which should be well defined, but Lirc tends to get it wrong) 
was incorrect.

> You're probably interested in the 
> exported .girr file, correct? I'll attach it to this email, hope I did 
> the capturing right. =] This is again using volume down from Pi A, with 
> -# 3 as mentioned.

Ouch!! Have you had a look at it (for example graphically in 
IrScrutinizer)? It is not even remotely close to what it is supposed to 
be. So we conclude that your /dev/lirc (lirc_rpi) is not even close to 
working correctly. Case closed!

It gets the timing all messed up. (Recall that generating a 38kHz 
carrier in software requires an interrupt every 1/(2 * 38000) = 0.000013 
s = 13 microseconds.)

How to do it better is another topic. Let me just remark that I know of 
an unofficial driver using the hardware PWM of the RPi: 
https://github.com/Al-/lirc_rpi_hardpwm . See also 
http://lirc.10951.n7.nabble.com/hardware-pulse-wave-modulation-modified-kernel-module-tc11134.html

To my knowledge, the lirc_rpi is deprecated by the Linux/RPi 
communities, but I am not sure it is for the "right" reason... ;-\