Kenwood protocol
Part 2
Pulsetrain carrier wave
38kHz written in C:
for(int i=0;i<=22;i++) //500us on
{
SETBIT(PORTB, 3); _delay_us(13);
CLEARBIT(PORTB, 3); _delay_us(13);
}
this gives a T of 26us (period time)
"better" oscilloscope
My old HP 54600A is nice but i cant record waveforms on it.
So i need to construct one that "can" -extremely budget one.
I'm connecting it to the audio card that has a sample rate of 96kHz
Pulsed code looks fine, read via IR photodiode -output is inverted
the 38kHz carrier is barely visible
Send pulse to stereo
Commandwise there is no "NXT"
I'll set that as play/pause instead:
NXT -> play pause => 13112214311541111
Seek button now include next track and if one keeps button pressed it seeks or scans
Code
PCB and unit prep on next page