suggestions about my wireless project

Hi every one
I need some suggestions about my project

I have two PICs
and I want to send three bytes which are the result of A to D conversion through RF modules from the sender to receiver

then display the three bytes on LCD
the three bytes should represent three physical parameters for example (temperature , humidity , pressure)

I'm going to use RS232 USART module to send and receive the data

and I'm planning to send these data every 0.5 second with 50ms interval

my problem is how to make the receiver distinguish every byte form its neighbor

my first Idea is to send a sync byte which has an already known data and make the receiver check for this byte to start receiving the data in sequence.

Any one has experience about that?

Thanx

Send the data as a fixed length packet made up of a start delimiter byte which is always the same, your data and then a checksum.

The receiver waits until it sees a byte with the correct value for the start delimiter, receives the fixed number of bytes that follow, then verifies the checksum. If the checksum is good you hand the data on, if not discard the packet and wait for another start delimiter.

That's how I've done it with this project and it works very well, even if the receiving unit is turned on in the middle of a stream of data it will 'sync' itself to the packets quite quickly

**broken link removed**

Pete

TronicBrain said:

I'm going to use RS232 USART module to send and receive the data

Click to expand...

DON'T - read my PIC RF tutorial instead, and you'll find out why not, and EXACTLY how to do it!.