MOSAUR UART Transmitter Receiver issues

Have a transmitter/reciever pair hooked up to two seperate boards. Each message I send is a Sync byte, then a Message Start byte, then an address byte, then an information byte. If I send the messages one at a time then the receiver gets the message about 1 out of 20 tries. If I send messages as fast as I can the receiver appears to be receiving most or all of them.

Also the transmitter works better when it sends hard coded signals instead of ones received through the USB cable from the computer.

Does anybody know how I can make sending single messages more reliable? Do you need any more info?

Thanks, Pooh

Yes more info needed. Specifically the frequency and modulation method of the transmitter.

It could be that you have a system that is allowing the AGC (automatic gain control) of the receiver to turn down when it is not sending anything. Then when it does send something say with negative amplitude modulation the receiver sensitivity is too low to work. However with continuous modulation the AGC circuit has time to adjust to the proper level.

I don’t know what a “Mosaur UART Transmitter Receiver” is, but if you’re using one of the low-cost 315/433MHz transmitter/receiver pairs then you ned to send a longer preamble before your message to “train” the receiver. The generally involves sending a series of 0x55 characters and a series of 0xAA characters.

You also might want to look into VirtualWire as a means to transmit and receive messages reliably.