I've checked the prices in Farnell for HCTL2xxx and the coders.

HCTL price is between 23 and 48 euros according to the model and the encoder Michael mentionned is 86 euros for a 256 PPR

So, the coder solution costs about 130 euros (unitary part) which is definitively too expensive for a such project.

Note that a 36PPR coder costs about 5 euros.
To be in accordance with my project, the solution shouldn't cost more than 15 euros for 1 part.


So, I've two solutions :
- Try a 36 PPR and software based decoder with the risk mentionned by Erik for the direction change
- Cancel the coder solution and use two push buttons instead !


Stephane