As you know several people have problem with the X5 joystick that is not
stable at all.

I began to write a patch for button-x5.c file to filter the button
status (http://www.rockbox.org/tracker/task/6787) but things are not
that easy.

The purpose of my filter is to return a button status only if the 3 last
keys status get from hardware (kept in an array) are not to spread (max
- min < 10).

If key status is not validated we can return : 0xFF (as if button was
released) or the last valid key status.

These two solutions bring issues. Here are examples :
- Returning 0xFF : If you are seeking a track by keeping "right" key
pushed, Rockbox may think you are pushing right again each time key
status is not validated. Several tracks can be skipped that way in very
short time.
- Returning last_valid : If we really push another button, the filter
will keep sending the last key status until the last 3 key status are
barely the same.

To solve this I think the filter should return the last valid key press
 and reset the array each time the button is released.

That's where I need some help. I'd like to know how to know a key is
released in order to reset the array.
Received on 2007-09-21