encode/decode manchester

[a_critchlow]

could anyone explain this to me in more detail please?



Encode:
For i = 0 to 7 ' loop for 8-bits
outword.0[(i*2)] = ~inbyte.0[i]
outword.0[(i*2)+1] = inbyte.0[i]
Next i '
Return

Decode::
For i = 0 to 7
outbyte.0[i] = ~inword.0[i<<1]
Next i
Return





The main line i dont understand is: outword.0[(i*2)] = ~inbyte.0[i]




thank you all for your time

[Ioannis]

The main line i dont understand is: outword.0[(i*2)] = ~inbyte.0[i]

That means bit i*2 of outword be the NOT (the inverse of) inbyte bit i

Ioannis

[Michael]

I don't get any of it.

Please, someone, a manchester encoding for dummies tutorial.

[Melanie]

Do a SEARCH on 'manchester' on this forum and all will be revealed.

[a_critchlow]

ive figured out the encoded part but i cant get the decoded part into my head:


outbyte.0[i] = ~inword.0[i<<1]


if the counter is at 0, it should put the first bit of the encoded data inversed into the decoded data var. but because of the <<1 it puts the second bit inversed into the first decoded var.




thanks.

[Ioannis]

ive figured out the encoded part but i cant get the decoded part into my head:

Don't bother. If you do not understand this code, there are many other codes doing the same thing. Or better, create your own.

The idea is this: if you have to send 0 then in manchester you will send 01 pair. If you have to send 1 then in manchester you will send 10 pair.

So, for the byte

1 0 0 1 1 0 0 1

the result would be:

10 01 01 10 10 01 01 10

Is it clear now? You can simply do an if-then-else sub routine for the encoder and also the same for the decoder (in reverse of course).

As Melanie stated, a search will reveal much more. This case is trivial by now...

Ioannis