This is a 433mhz wireless connection where the 'communication. consists of the 4 data bits on the HT12D/E. It only has to turn a few things on and off. I like the 433mhz/encoder/decoder setup for this because it is stand alone, no protocols needed and quite adequate for the task.
I guess it seemed like a weird use of these but I like it, if only the chips would behave as the datasheets state. I've bradboarded exactly what is shown in the diagrams. I've been doing this kind work in R&D for over 30 years and never felt stupider or more dumnbfounded in not getting this to work. The assressing only maches up when all are left floating, datasheet says as long as they match. The other issue is the receiver 4 bits don't change state when xmt bits are changed, makes no sense. I breadboarded it a few months ago and it worked as should. I just went and got a new batch of chips thinking I might have some defective ones. Using the same bench supply as before. Honestly my lab feels like the Twilight Zone with these ICs lol.