Apparently, they just mux them all, I can sit there with either the transmitter (with my four buttons to trigger it), or a keyfob and press one, two, three, or all four buttons, and all the receiver lights react properly at all times.
@stan2004 posted:So if you continuously trigger say CH1, the TX module will transmit continuous packets (~22 msec long, every ~30 msec). But if CH1 is transmitting and you additionally press, say, CH3 then the packets switch to CH3 packets? Or are the packets alternating CH1, CH3, CH1, CH3, etc.? Then you release CH3 and the packets revert to continuous CH1 packets?
Correct, exactly what you'd expect to happen happens. It's like the four channels are muxed, and they always transmit what they should to manage the channels.
@stan2004 posted:When you say "totally independent" I'm a bit confused. If all 4 channels are triggered simultaneously, what is transmitted?
I confess, I can't trigger them truly simultaneously, but I suspect they're managing that internally since as close as I can get with two buttons, I never see anything anomalous in the received data. My belief is they manage the four channels in the keyfob or transmitter module and trigger the outputs properly.
I wouldn't be at all surprised to see that the transmitted word has a bit for each channel, and they're just setting and resetting one or more of them based in their inputs. I know that's how I'd design it if I were doing it. I suspect finding a specification for the 1527 protocol might answer that question.
