Some combination of data, followed by logically inverted data (as an 'opposite' 
data stream), parity bits (or your code) on each, and repeating will probably 
get the data through, and if you don't get 2 good answers out of n (preferably 
1 real and one inverted agree with good parity, at least), then light the "I 
give up" LED. ;)

If this needs to happen only once every n seconds, constantly repeat the data 
and sample at the receiver every n seconds instead, but be continually checking 
as above. You'll have LOTs of redundancy to work with by the time you need the 
sample.

-Skip


Bob Blick wrote:
> Basically I don't have much data to move, and I want correction for
> multiple bits. 
> 
> The hamming method I was using has almost 100% overhead, only corrects
> single bit errors and uses two tables.
> 
> All the examples I've seen on the web that do what I want are for long
> groups of bytes and use things like Reed-Solomon coding. Those methods
> are way too clever for me to recreate for just a couple of bytes. As I
> said, I'm not a computer scientist.
> 
> Thanks,
> 
> Bob
> 
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