I understand what you are saying with the one way transmission but after doing tests it seems like I get almost no noise at all once the transmitter is on. Meaning once the transmitter has power , the receiver will not output any byte at all - no noise at all ( well ok once in a while I'll get an occasional bad byte) .
Would it be safe to use my packet system and just send each packet twice? (chances are that the receiver will receive at least one of those packets).
As for the checksum business: In my application there are 20 receivers all tuned to the same channel . Each receiver has two addresses. So thats a total of 40 addresses. Meaning if I want to control all 40 addresses at the same time ( which is unlikely in my application) - then I have to send 40 packets. That's half as many packets per second as I get now at 2400 baud. My worry is that if one of the bytes in a packet is corrupted then I'm screwed. (55,56,95) results in a different action then (55,56,59).
If anything I could remove the start bit and have it check for addresses right away. But I guess I can keep it , I mean I already have the system functioning two times as good as I need it . I only need 40 packets a second and I get 80 bytes a second. ( which is good
Also as dunk said I could send the packet twice each time. I guess that could work but it would halve my bandwidth. I might have to do it because I was thinking - if the checksum is NOT manchester encoded(which will usually be the case) then it could screw up the reading of the other bytes that are coming in later. Right?
By the way I'm getting exactly 80% - 240/300 . I guess I could get higher if that damn delay wasn't needed.
I'll up it to 4800 baud and do some tests and see how it goes.